NOTIZIARIO Neutroni e Luce di Sincrotrone - Issue 11 n.2, 2006

Vol. 11 n. 2 July 2006 - Aut. Trib. Roma n. 124/96 del 22-03-96 - Sped. Abb. Post. 70% Filiale di Roma - C.N.R. p.le A. Moro 7, 00185 Roma

NOTIZIARIONeutroni e Luce di Sincrotrone

Rivista delConsiglio Nazionaledelle Ricerche

ISSN 1592-7822

Cover photo:Laboratory scientists, engineers,instrument scientists and othersat the first neutrons producedon Friday, April 29, 2006 at theSpallation Neutron Source.

published by CNR in collaborationwith the Faculty of Sciences and thePhysics Department of the Universityof Rome “Tor Vergata”.

Vol. 11 n. 2 Luglio 2006Autorizzazione del Tribunale diRoma n. 124/96 del 22-03-96

EDITOR:

C. Andreani

EXECUTIVE EDITORS:

M. Apice, P. Bosi, D. Catena

EDITORIAL OFFICE:

L. Avaldi, S. ImbertiG. Paolucci, R. Triolo, M. Zoppi

EDITORIAL SERVICE AND ADVERTISINGFOR EUROPE AND USA:

P. Casella

CORRESPONDENTS AND FACILITIES:

J. Bellingham (NMI3)M. Bertolo (I3-IA-SFS)A.E. Ekkebus (SNS)

ON LINE VERSION

V. Buttaro

CONTRIBUTORS TO THIS ISSUE:

M. Bertolo, M. Blaauw, G. Cicognani, D. Colognesi,A.E. Ekkebus, M. Helm, P. Michel, W. Mondelaers, H. Postma, P. Schillebeeckx, J. TomkinsonGRAPHIC AND PRINTING:

om graficavia Fabrizio Luscino 7300174 RomaFinito di stamparenel mese di Luglio 2006

PREVIOUS ISSUES ANDEDITORIAL INFORMATION:

Pina CasellaUniversità degli Studidi Roma “Tor Vergata”Tel: +39 06 72594560E-mail: [email protected]

Vol. 11 n. 2 July 2006


S U M M A R Y

Rivista delConsiglio Nazionaledelle Ricerche

EDITORIAL NEWSSNS Up and Spalling .............................................................. 2A. Womac

SCIENTIFIC REVIEWSHydrogen vibrational dynamics in ionic metalhydrides revealed through inelastic neutronscattering ..................................................................................... 4D. Colognesi, M. Zoppi

Neutron-resonance capture as a tool to analyse theinternal compositions of objects non-destructively .... 14H. Postma, P. Schillebeeckx

RESEARCH INFRASTRUCTURESGELINA, a neutron time-of-flight facility forhigh-resolution neutron data measurements................ 19W. Mondelaers, P. Schillebeeckx

M & N & SR NEWSLightsources.org enters its second year of operation.... 26M. Bertolo

Reactor Institute Delft and the R3 departmentThe academic Dutch neutron facility................................. 26M. Blaauw

ILL Next standard proposal round .................................. 28G. Cicognani

AP.G.RA.D(E), Application of γ-raydiffraction (October - November 2006)........................... 29G. Cicognani

Jefferson Lab’s CEBAF Continues Experiments WhileGearing Up for an Increase in Energy ............................ 30A.E. Ekkebus

Spallation Neutron Source - Progress February 2006 ... 32A.E. Ekkebus

FELBE: a new infrared free-electron-laser userfacility ......................................................................................... 33M. Helm, P. Michel

NEWS AND MEETING REPORTS .............................................................36

CALL FOR PROPOSAL ........................................................................... 39

CALENDAR ............................................................................................... 40

FACILITIES ............................................................................................... 43


www.cnr.it/neutronielucedisincrotrone

2

NOTIZIARIO NEUTRONI E LUCE DI SINCROTRONE • Vol. 11 n. 2 July 2006

EDITORIAL NEWS

2

NOTIZIARIO NEUTRONI E LUCE DI S

After seven years of construction, the Spallation

Neutron Source (SNS) at Oak Ridge National Lab-

oratory (ORNL) in Oak Ridge, Tenn., is successful-

ly producing neutrons. At 2:04 p.m. EDT, April 28,

2006, scientists at SNS watched, anticipating suc-

cess, as protons hit right on the target, spalling

neutrons and marking a major milestone for the

$1.4 billion research facility. Within 88 minutes of

the first beam on target, a pulse of 1013 protons was

delivered to the target completing proton and neu-

tron flux criteria for project completion.

On May 20, the first of the SNS instruments, the

Backscattering Spectrometer, opened the primary

shutter and counted neutrons.

Another milestone was met at the same time: these

neutrons were the first “cold neutrons” produced

at SNS from the cryogenic moderator system.

Success continued on May 23 when the Backscat-

tering Spectrometer became the first instrument to

record time-of-flight data. The 25g sample of fluo-

rinated mica was placed in a 3 cm by 3 cm neutron

beam with a time averaged proton power on target

of 185 watts. Four detector tubes counted for 822

seconds. The accompanying chart displays the

118k neutrons counted. The neutron diffraction

peaks are clearly visible.

The SNS project is a unique partnership among

six Department of Energy (DOE) National Labo-

ratories, making SNS the first facility designed

and built through a precedent-setting collabora-

tion. Lawrence Berkeley National Laboratory was

responsible for the front-end system that gener-

ates the proton beam; Los Alamos National Labo-

ratory and Thomas Jefferson National Accelerator

Facility designed and built the room-temperature

and superconducting sections of the linac;

Brookhaven National Laboratory designed the

proton accumulator ring; ORNL designed and

built the target station; and Argonne National

Laboratory was responsible for hosting the initial

instrument development.

“To arrive at this point, on budget, on scope, and

SNS Up and Spalling

Figure 1. Fluorinated mica produced these neutron diffraction peaks at SNS.

3

Vol. 11 n. 2 July 2006 • NOTIZIARIO NEUTRONI E LUCE DI SINCROTRONE

on schedule is a tribute to the six national labs

working together. I think this is an exceptional ac-

complishment,” said Jeff Wadsworth, ORNL di-

rector.

With the construction phase now over and the

commissioning phase beginning, SNS will soon

have three instruments, the Backscattering Spec-

trometer and the Liquids and Magnetism Reflec-

tometers, operational for initial users. Initial users

will submit research proposals, which will be peer-

reviewed and recommended based on scientific

and technological impact, as well as experience of

the experiment team. By fall 2006, SNS expects ini-

tial users to be selected for these first three instru-

ments. Future operational timelines at SNS include

the following:

• Summer 2007: Power level exceeds 100kW

• Fall 2007: General User Program for first three

instruments

• Winter 2008: 1MW capability with 7

instruments in General User Program

Continuing the outreach efforts for ORNL’s major

neutron scattering facilities, we are hosting an in-

ternational “Imaging and Neutrons 2006” confer-

ence, October 23-25th, which will give researchers

an opportunity to create a multi-disciplinary re-

search network for applications of neutron imag-

ing; identify needs and potential contributions of

imaging with neutrons; recognize possible new

imaging techniques; and produce a report identify-

ing possible neutron research directions for the in-

ternational science community.

The multi-disciplinary conference incorporates a

variety of applications, including the medical/

biomedical community; chemistry, engineering,

geology, and physics; energy and nuclear power;

material research; cultural heritage; and home-

land security.

The workshop is being sponsored by ORNL, the

European Community’s Integrated Infrastructure

Initiative for Neutron Scattering and Muon Spec-

troscopy (NMI3), Oak Ridge Associated Universi-

ties, and the Joint Institute for Neutron sciences.

For more information, visit the website at

www.sns.gov/workshops/ian2006. For more in-

formation on SNS, its operations or related work-

shops, visit our website www.sns.gov.

Amanda Womac

ORNL

EDITORIAL NEWS

SNS CHRONOLOGY

December 1999 – Groundbreaking ceremony

November 2002 – Front-end commissioning begins

April 2003 – Linac and target equipmentinstallation begins

August 2003 – Ring equipment installation begins

March 2004 – Instrument installation begins

June 2004 – Project staff moves to construction site

January 2005 – Warm linac commissioningcompleted

May 2005 – First target module delivered

June 2005 – Construction hours without a lostworkday reaches 4 million

September 2005 – Commissioning of entire linaccompleted

December 2005 – Mercury loaded into targetsystem

January 2006 – Beam accumulated in ring andextracted to dump; successful testing of mercuryloop

April 2006 – First beam on target: Critical Decisionfor performance test accomplished

May 2006 – First instrument, the BackscatteringSpectrometer, opened primary shutter andcounted the first “cold neutrons” produced fromthe cryogenic moderator system

SCIENTIFIC REVIEWS

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AbstractInelastic neutron scattering spectra from polycrystallinealkali (Li, Na, Rb and Cs) and heavy alkaline-earth (Ca,Sr and Ba) hydrides, measured on TOSCA-II spectrome-ter at low temperature in the energy transfer range 3meV<E<500 meV, are reported. From the medium-ener-gy regions, coinciding with the optical phonon bands,accurate generalized self inelastic structure factors and(if possible) hydrogen-projected densities of phononstates are extracted and compared to ab-initio lattice dy-namics results. The overall agreement is found satisfac-tory. In addition, in CaH2, simulations provide a com-pelling support to a recent physical interpretation of therecorded spectral features and allow to separate the con-tributions produced by the two non-equivalent hydro-gen atoms. In conclusion, incoherent inelastic neutronspectroscopy proves to be a stringent validation tool forlattice dynamics simulations of H-containing materials.Keywords: Metal hydrides; Inelastic neutron scattering;Lattice dynamics

IntroductionIonic hydrides have gained a new wave of interest in thelast ten years, mainly in connection with the hydrogenstorage problem, where, for example, alkali and alkaline-earth borohydrides and aluminohydrides seem to play arelevant role [1]. The simplest ionic hydrides can beformed by H through reaction with an alkali metal [2].The first x-ray diffraction studies [3] showed that LiH,NaH, KH, RbH and CsH (AlkH for short) crystallizewith the rock-salt structure at ambient pressure. In thesematerials hydrogen is present in the form of anion: elec-tron distribution investigations [4] estimated the H ioniceffective charge in AlkH to fall in the range between -0.93 and -1.11 electron charges, indicating that alkalimetal hydrides are probably similar to the respectivehalides as regards the electronic structure. In view of thisfeature, which gives rise to long-range interactions be-tween hydrogen atoms, the H dynamics in these com-pounds is expected to be very different from that in tran-sition-metal hydrides. Nevertheless, virtually only LiHhas been extensively studied [5], both theoretically andexperimentally, since it exhibits a straightforward rock-salt structure having only four electrons per asymmetric

unit, which makes it the simplest ionic crystal in terms ofelectronic structure. Because of these peculiar physicalproperties, LiH lattice is well described, both structural-ly [6] and dynamically [7-9]. However, as far as NaH,KH, RbH and CsH are concerned, besides incomplete ex-perimental studies on NaH vibrational spectra [9], onlylattice dynamics calculation has been reported in Ref.[10] before our investigations. Given this scanty sce-nario, a detailed experimental study on the whole seriesof alkali metal hydrides was planned [11,12] in order toprovide the first high-quality spectroscopic measure-ments on all the AlkH. We have proved that the com-bined use of Incoherent Inelastic Neutron Scattering (IINS),from which the Hydrogen-projected Density of PhononStates (H-DoPS) can be worked out, and of ab-initio simu-lations, from which important physical quantities can bederived (lattice constants, bulk modulus, phonon disper-sion curves, density of phonon states etc.) can provide adeep insight into the problem of the hydrogen dynamicsin condensed matter.On the other hand, differently from AlkH, which exhibitthe same ambient-pressure structure moving from Li toCs, alkaline earth hydrides are characterized by threedistinct subsets: BeH2, unstable and body-centered or-thorhombic with an Ibam space group [13], MgH2, welldescribed and showing a rutile-type structure (tetrago-nal, P42/mnm) a low pressure [14], and, finally, Ca, Sr andBa dihydrides, isomorphic and crystallizing with an or-thorhombic lattice (at low pressure and temperatures be-low 600oC), exhibiting the Pnma space group. Thesethree Heavy Alkaline-Earth Hydrides (labeled HAEH2 inshort) were structurally studied for the first time in 1935[15], when the metal atom position was determinedthrough standard x-ray powder diffraction: alkalineearth atoms appeared arranged in a slightly-distortedhexagonal close-packed structure. On the other hand,the hydrogen locations were not properly resolved.However further neutron scattering experiments ondeuterated powder samples (CaD2 [16], SrD2 [17] andBaD2 [18]) showed a slightly distorted PbCl2-type struc-ture for all the three HAEH2. Finally, recent x-ray single-crystal measurements on CaD2 and SrD2 [19], and onBaH2 [20] basically confirmed the neutron scatteringfindings with few minor differences.

Hydrogen vibrational dynamics in ionic metal hydridesrevealed through inelastic neutron scatteringD. Colognesi and M. ZoppiConsiglio Nazionale delle RicercheIstituto dei Sistemi Complessi: Sezione di Firenze

Via Madonna del Piano 1050019 Sesto Fiorentino (FI), Italy

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If the situation concerning the microscopic structure ofHAEH2 could be considered as quite satisfactory, thiswas not at all the case about their lattice dynamics,where only two experimental studies had been so far re-ported, both making use of the IINS technique in orderto extract the hydrogen vibrational spectra. However,while one work [21] showed good quality data fromCaH2 at temperatures of 10 K and 295 K, the other, whichhad the ambition to explore the complete series ofHAEH2 [22], offered only low-resolution spectra in a nar-row energy transfer range (50-155 meV), due to the limi-tations of the neutron equipment of that time. For thisreason we have reported new incoherent inelastic mea-surements on all the HAEH2 using a modern neutronspectrometer, which exhibits both good energy resolu-tion and wide energy transfer range [23].Finally, if one considers the first-principles simulationsof the HAEH2 properties, the present scenario alsolooked rather unsatisfactory. Only two groups have de-voted some effort to this class of compounds: El-Gridaniand coworkers have simulated the elastic, electronic andstructural properties of CaH2 [24,25], SrH2 [26] and BaH2

[27] making use of the Hartree-Fock or the pseudo-po-tential method in connection with the CRYSTAL95 pro-gram, while Smithson et al. [28] studied the stability andelectronic structure of all the metal hydrides (includingof course HAEH2) through the VASP simulation pack-age. However, no information on the lattice dynamicswas reported by either groups. This insufficient situationprompted us to develop independent ab-initio lattice dy-namics simulations in order to check the residual struc-tural ambiguities of HAEH2 and, moreover, to extractphonon spectra to be compared with the experimentalneutron results [23].The rest of the article will be organized as follows: ex-perimental IINS procedure will be dealt with in Sect. 2,and spectral data analysis will be shortly described inSect. 3, while Sect. 4 will be devoted to a brief explana-tion of the ab-initio simulations. In Sect. 5 we will dis-cuss the experimental results in comparison with thesimulation ones. Finally, Sect. 6 will contain the conclu-sions of the present study.

Experimental procedureThe IINS measurements were carried out using theTOSCA-II inelastic spectrometer of the ISIS pulsed neu-tron source at Rutherford Appleton Laboratory, Chilton,Didcot (UK). TOSCA-II is a crystal-analyzer inverse-geometry spectrometer [29], where the final neutron en-ergy, E1, is selected through two sets of pyrolyticgraphite crystal analyzers placed in forward-scattering(at around 42.6° with respect to the incident beam) andin back-scattering (at about 137.7°).This arrangement fixes the nominal scattered neutron

energy to E1=3.35 meV (forward-scattering) and toE1=3.32 meV (back-scattering). Higher-order Bragg re-flections are filtered out by 120 mm-thick berylliumblocks cooled down to a temperature lower than 30 K.The incident neutron beam, on the other hand, spans abroad energy range allowing coverage of an extendedenergy transfer, E, region: 3 meV<E<500 meV. Because ofthe fixed geometry of this spectrometer, the wave-vectortransfer, Q, is related to the energy transfer through amonotonic function, roughly proportional to the squareroot of the incoming neutron energy, E0: Q=Q(E0)∝√E0.TOSCA-II has an excellent energy resolution in the ac-cessible energy transfer range (∆E/E0≅1.5–3%). The sample cells used for LiH, NaH, CaH2, SrH2 andBaH2 were made of aluminum with a slab geometry(size: 34×48 mm2, with 1 mm-thick walls and 5 mm of in-ternal gap). Special care was devoted to preventing pos-sible hydroxide formation during the sample loadingprocedure. The measurements on KH, RbH and CsH re-quired, in contrast, a different choice of the sample con-tainer, due to the very unstable and sensitive nature ofthese three hydrides. After their syntheses they were ac-curately sealed in square quartz cells (40 x 40 mm2, 7.5mm thick). In Tab. I we have summarized various experimental de-tails concerning the metal hydrides, all in the form ofpolycrystalline powder as checked by means of standardx-ray diffraction. Before the actual measurements, thetwo empty cells were cooled down to the low tempera-ture of the experiment, and their Time-of-Flight (ToF)spectra recorded up to an Integrated Proton Current (IPC)of 344.1 and 3451.4 µA h for the aluminum and thequartz container, respectively. Then the hydride samples were placed in the cryostat atT=20 K (except SrH2, measured at T=16 K) for the IINSmeasurements. Raw IINS spectra for all the AlKH andHAEH2 are reported in Fig. 1, while further experimentaldetails can be found in Refs. [11,12,23].

sample T(K) IPC(µµAh) mass(g) p(%) purity(wt.)

LiH 20.1(1) 2101.0 1.4 15.96 97%NaH 20.1(1) 660.5 3.1 13.21 95%KH 20.0(1) 3284.0 2.6 6.02 >97%RbH 20.0(1) 3213.9 5.9 7.53 >97%CsH 20.0(1) 3124.9 9.2 3.32 >95%CaH2 20.0(3) 1828.9 3.9 16.98 98%SrH2 16.0(3) 3248.1 6.1 12.65 99.5%BaH2 20.0(3) 2551.9 6.4 8.12 99.5%

Tab. I. Sample description, including experimental temperature T, inte-grated proton current IPC, mass, sample scattering power p (at E0=103.3meV), and purity.

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Data analysisThe experimental back-scattering ToF spectra weretransformed into energy transfer data, detector by detec-tor, making use of the standard TOSCA-II routines avail-able on the spectrometer. Spectra were added together ina single data block (disregarding forward-scattering databecause of their larger instrumental background). This grouping procedure was justified by the narrow an-gular range spanned by detectors, since the correspond-ing full-width-at-half-maximum, x, was estimated to beonly 8.32° [29]. In this way we produced double-differ-ential cross-section measurements along the TOSCA-IIkinematic path (Q(E), E) of the (hydride sample + can)systems, plus, of course, the empty cans. Data were thencorrected for the k1/k0 kinematic factor (see Fig. 1), andthe empty-can contribution was properly subtracted[30], taking into account the E0-dependent sample trans-mission as explained below.At this stage the important corrections for self-absorptionattenuation (especially relevant for LiH and CsH, sinceσabs(Li)=70.5·10-28 m2 and σabs(Cs)=29.0·10-28 m2 at E0=25.8meV [31]) and multiple scattering contamination wereperformed through the analytical approach suggested byAgrawal and Sears in the case of a flat slab-like sample

[32]. However this method needed two important in-puts, which are related to the microscopic dynamics ofthe measured sample, namely: (a) the hydride total scat-tering cross-section σt(E0), known to be largely depen-dent on E0 because of H; (b) an estimate of the hydridescattering law to be folded with itself in order to gener-ate multiple scattering contributions. Needless to say thedetermination of this scattering law is actually the mainaim of the present work. Both procedures (i.e. self ab-sorption and multiple scattering corrections) were ac-complished in the framework of the incoherent approxi-mation [33]. This was totally justified by the preponder-ance of scattering from the H nuclei and by the polycrys-talline nature of the samples. The hydride total scatter-ing cross-section, σt(E0), was estimated summing thesmall metal contribution (i.e. bound cross-section, con-stant in E0) to the large and E0-dependent H part. The lat-ter was evaluated from the approximate H-DoPS, ZH(E),reported in Refs. [8,10,21,22], making use of Eqs. (3), (11)and (12) of Ref. [34]. A test of the σt(E0) sensitivity to thedetails of the phonon frequency distributions was alsoperformed on LiH and CaH2, since a more accurateZH(E) were available in these cases [8,21].Only minor differences were detected, showing that inthese compounds σt(E0) is only weakly influenced by theparticulars of ZH(E). A more delicate issue was the choiceof the model self scattering laws, Ss

(n)(Q,E), (with nstanding for metal or proton) to be used for the multiplescattering estimate, since the approach followed forσt(E0) was regarded as too coarse, at least for the NaH-CsH series, and for SrH2 and BaH2, where no reasonablyaccurate ZH(E) was accessible. In addition, it has to benoted that Eqs. (11) and (12) of Ref. [34] are not strictlyrigorous in the case of alkaline earth hydrides, since

Figure 1. Raw neutron spectra from alkali metal hydrides (a), and heavyalkaline-earth hydrides (b) measured in backscattering on TOSCA-II atT<_20 K. Spectra have been vertically shifted and normalized to similarpeak height for graphic reasons.

Figure 2. Evaluation of the double-inelastic-scattering (red dotted curve)for NaH at T=20 K, together with the TOSCA-II experimental data (bluecircles with error bars). The estimate of the sample-dependent back-ground has also been reported (green dashed line).

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their crystal structure is not exactly cubic (isotropic) and,moreover, two non-equivalent H sites (H1 and H2 [16-20]) exist in the lattice, and then two distinct Ss

(H)(Q,E) func-tions should be employed for estimating multiple scat-tering; a requirement that was obviously thoroughly im-possible at this stage.Thus, retaining the aforementioned approximation ofRef. [34], two model DoPS (i.e. ZH(E) and ZMet(E)) wereset up for each hydride sample, using all the pieces of in-formation available from the present uncorrected neu-tron spectra, from Refs. [10,22], and also from the ab-ini-tio simulations of Sect. 4, and then combining them to-gether through the existing physical constraints as ex-plained in detail in Ref. [35]. Multiple scattering contri-butions were found to be modest, but not at all negligi-ble, in the energy transfer interval of interest (i.e. 50meV<E<150 meV) containing the optical single-phononscattering bands (also known as “fundamental”). How-ever, as already verified in various other cases [36], a rel-evant multiple scattering term on crystal-analyzer in-verse-geometry spectrometers is composed of one in-elastic scattering event together with one (or more) elas-tic scattering events. This term appeared almost indistin-guishable from the single (inelastic) scattering and thenit was not subtracted from the experimental neutronspectra. On the contrary, multiple scattering contribu-tions containing two (or more) inelastic scattering eventswere carefully evaluated, ranging between 3.0% (KH)and 10.5% (CaH2) of the total neutron counts in backscat-tering in the E-interval of interest. Finally, these esti-mates were removed from the processed neutron spectra(see Fig. 2), which were finally transformed into general-ized self inelastic structure factors, Σ(Q,E):

(1)

where cn is the concentration of the nth non-equivalentatomic species, and σn its total scattering cross-section(bound).By inspecting the Σ(Q,E) spectrum from CaH2 in Fig. 3,some clear Ca(OH)2 contaminations have been detected,similarly to what was observed in Ref. [21], despite thecare used in the cell loading process (see Sect. 2 for de-tails), being some hydroxide probably already present inthe commercial hydride samples.These unwanted features were removed making use of aprevious IINS measurement on Ca(OH)2 [37], operatedon a similar spectrometer (namely TFXA, i.e. TOSCA’sprecursor): calcium hydroxide data were processed inthe same way as CaH2 and, after a proper scaling, sub-

tracted from the contaminated calcium dihydride spec-trum. As for the other hydrides, no sign of hydroxidecontamination was detected in the low-energy zone.In the case of AlkH, exhibiting an isotropic structurewith only one single H site, the extraction of the H-DoPSwas attempted. The last procedure before this operationwas the evaluation and subtraction of the tiny metalscattering and of the more conspicuous multiphononcontribution, containing both optical-plus-acoustic com-binations and optical-plus-optical overtones. The multi-phonon contribution was not completely negligible be-cause of the relatively high Q-values attained by

,),(),(n

(n)snn∑=Σ EQScEQ σ

Figure 3. Generalized self inelastic structure factor from CaH2 (a), SrH2

(b), and BaH2 (c), recorded in back-scattering at T<_20 K.

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TOSCA-II in the 50 meV<E<150 meV experimentalrange, namely 6.1 Å-1<Q<9.6 Å-1 (in back-scattering). Af-ter removing the practically negligible metal contribu-tion to Σ(Q,E), processed AlkH data were proportional tothe self inelastic structure factor [14] for the H ions,Ss

(H)(Q,E). Due to the isotropic nature of the AlkH crys-tals, such a quantity could be easily interpreted as thesum of spherically averaged n-phonon terms (n=0, 1,2...), each describing a neutron scattering process of cre-ation or annihilation of n vibrational quanta in the crys-tal lattice. As far as the H-DoPS is concerned, the onlyuseful contribution of the experimental spectrum is theone-phonon component of Ss

(H)(Q,E), namely Ss,+1(H)(Q,E).

The following equation shows its relation with the H-projected density of phonon states:

(2)

where MH is the proton mass, kB is the Boltzmann con-stant and 2WH(Q) is the well-known Debye–Waller fac-tor, related to the mean square displacement of H (and tothe H-DoPS itself) via:

(3)

The full expansion of Ss(H)(Q,E) in terms of phonon oper-

ators was employed in combination with the simulatedH-projected DoPS to evaluate the multiphonon scatter-ing. Its contribution in the optical-band energy range(50–150 meV) is shown for NaH in Fig. 4. Thus experi-mental Ss

(H)(Q,E) spectra were analyzed through an itera-

tive procedure [34,35], aiming to simultaneously extractZH(E) and 2WH(Q) by means of Eqs. (2) and (3). Techni-calities can be found in Refs. [11,12,35], while the experi-mental ZH(E) determinations obtained are reported inFigs. 5 and 6. From these ZH(E) data, making use of nor-mal and Bose-corrected moment sum rules [39], we werealso able to derive three important physical quantitiesrelated to the hydrogen dynamics in these hydrides,namely: the H mean square displacement ⟨u2⟩H, the H meankinetic energy ⟨T⟩H, and the H Einstein frequency Ω0,H, allreported in Tab. II.

First-principle simulationThe vibrational dynamics of the aforementioned ionichydrides (except LiH) has been simulated through a to-tally ab-initio method based on the density functionaltheory and making use of pseudo-potentials and aplane-wave basis. Calculations were carried out usingthe plane-wave density functional theory as implement-ed in the ABINIT code [40]. Here, two main limitationsoccur. The first is the use of pseudo-potentials to repre-sent the core electrons, allowing us only to include rela-tivistic effects in an essentially non-relativistic code. Thischoice is of the maximum importance for reducing thenumber of plane waves representing the electronicwave-function to a level that is tractable with the cur-rently available computer power. The second limitationconcerns the use of the density functional theory, wheretwo general approaches apply: in the Local Density Ap-proximation (LDA) the exchange and correlation energiesare described as functions of the local electron density ateach point, while in the Generalized Gradient Approxima-tion (GGA), electron density gradients are also taken intoaccount. It has been shown that the GGA provides re-sults in better agreement with experimental data thanthose obtained from the LDA when low-Z elements are

sample ⟨⟨u2⟩⟩H (Å2) ⟨⟨T⟩⟩H (meV) ΩΩ0,H (meV)

LiH 0.062(1) 80(1) 109.2(9)

NaH 0.0736(4) 66.9(4) 90.7(5)

KH 0.0856(5) 57.7(4) 78.2(6)

RbH 0.0893(4) 55.0(2) 74.4(4)

CsH 0.0953(3) 51.3(2) 69.5(3)

Figure 4. Evaluation of the multiphonon contributions (red dashedcurve) for NaH at T=20 K, together with the TOSCA-II single-scatteringexperimental data (blue circles with error bars).

Tab. II. Mean square displacements ⟨u2⟩H, mean kinetic energies ⟨T⟩H, andEinstein frequencies Ω0,H of hydrogen in alkali metal hydrides at T=20 Kfrom the present inelastic neutron scattering measurements.

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involved. However, the opposite is found if high-Z ele-ments are considered. On the other hand, Bellaiche et al.[41] have calculated the equation of state for LiH andLiD using Hartree–Fock theory and two different LDAfunctionals, considering both the pseudo-potential and

the all-electron approaches. Results from Hartree–Fockand LDA approaches differ less than 1%, indicating that,at least for this system, the equation of state depends on-ly very weakly on the electron correlation. Because, inprinciple, for the solid state, neither LDA nor GGA haveclearly proved their superiority, it was decided to carryout the AlkH simulations considering the LDA (less de-manding as regards computer time), using theTeter–Padé parametrization [42] and the norm-conserv-ing Troullier–Martins pseudo-potentials [43]. Some ex-ceptions were represented by K, Ca, Sr and Ba ions,where the Hartwigsen–Goedecker–Hutter pseudo-po-tentials had to be employed [44]. As for the HAEH2 se-ries the Generalized Gradient Approximation (GGA) hasbeen preferred, using the parameterization introducedby Perdew, Burke and Ernzerhof [45]. The reasons forthis choice can be found in Refs. [12,46], where it isshown that standard energy minimization methods us-ing GGA give an adequate lattice geometry although thecomputationally-prohibitive thermal and zero point ef-fects are not included. In addition, as the (n-1)s and(n-1)p electrons are known to be important for the alka-line earth elements, semi-core electrons were explicitlyconsidered in the appropriate pseudo-potentials.

Figure 6. Comparison between experimental and simulated optical branches of the hydrogen-projected density of phonon states in heavy alkali hy-drides: neutron scattering experimental results (red circles with error bars) and ab-initio simulations (blue curves).

Figure 5. Hydrogen-projected density of phonon states in LiH. The ex-perimentally-determined result is plotted as magenta circles, the red his-togram represents a DDM13-potential lattice dynamics simulation [10],the blue line a SM7-potential lattice dynamics simulation [8], and thegreen line the old neutron measurement [8]. See main text for details.

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It was carefully verified for all simulations that full con-vergence was achieved as regards both the number of k-points in the reciprocal space and the energy cut-off ofthe plane waves. So, the final choice in the hydride cal-culations was a mesh of 8x8x8 points for AlkH (and4x4x4 for HAEH2) in the reciprocal space, and a cut-offof 1360.72 eV. In order to calculate well-defined densitiesof phonon states, phonons were determined on a16x16x16 grid of points in the first Brillouin zone. How-ever a full electronic calculation on such a grid was notnecessary, since an accurate interpolation procedurethrough the ANADDB [47] program was used. ABINITresults for ZH(E) for heavy AlkH are plotted in Fig. 6,while further details on the simulation work on thesemetal hydrides can be found in Ref. [46]. Finally, the ac-tual IINS spectra for HAEH2 were generated using theACLIMAX code [38], which takes exactly into accountsthermal and powder-average effects, together with over-

tones and combinations up to the tenth quantum event.Simulated generalized self inelastic structure factors arereported in Fig. 7 (together with their respective funda-mental components).

DiscussionA comparison among the various determinations (bothexperimental and simulated) of the H-DoPS for LiHcould be finally established at this stage. In Fig. 5, fourH-DoPS estimates have been plotted together in the fre-quency region concerning the two optical bands, namelythe Translational Optical (TO) and the Longitudinal Optical(LO), which actually contain more than 97% of the totalZH(E) area [10]. The present IINS experimental result [11]is plotted as magenta circles, the red histogram repre-sents the DDM13-potential lattice dynamics simulation[10], the dotted blue line is the SM7-potential lattice dy-namics simulation from Verble et al. [8], and the dashedgreen line stands for the old IINS measurement fromZemlianov et al. [8]. As a preliminary comment, one caneasily observe the existence of a fair general agreementamong all the four ZH(E) in the TO range, at least as faras the peak position is concerned. On the contrary, theLO region looks much more uncertain, the peak centervarying from 115 meV up to 140 meV. The reason forsuch a behavior is easily understandable for SM7 andDDM13 data: these lattice dynamics calculations madeuse of the some parameters (7 and 13, respectively) de-rived from a fit of the same LiD dispersion curves mea-sured by Verble et al. [8] (for a detailed comparative dis-cussion on the differences between the SM7 and DDM13H-DoPS calculations see Ref. [10]). By a simple inspec-tion of these experimental dispersion curves, it is clearthat the LO neutron groups are really few (four valuesplus one infra-red measurement at the Γ point). Howev-er the disagreement between the present IINS ZH(E) andthe old one is difficult to explain, so that we are inclinedto think that these discrepancies are due to experimentalimperfections in the data analysis of the latter (e.g. mul-tiple scattering or multiphonon scattering subtraction).Selecting the two most recent experimental and simulat-ed ZH(E), namely the present IINS and the DDM13 esti-mates, we can observe an overall semi-quantitativeagreement, the main discrepancies being concentrated intwo regions: at low energy, in the onset of TO band (65meV<E<90 meV), and in the LO band as a whole (112meV<E<145 meV). As for the latter, a simple energy shiftof 4.5 meV seems sufficient to largely reconcile IINS andDDM13, while in the former case, neutron data appearsomehow broader than lattice dynamical ones (the IINSwidth being about 5.1 meV wider than the DDM13 one).Considering the TOSCA-II energy resolution in this region(1.6 meV), a simple explanation based only on experimen-tal effects can be easily discarded. However such a broad-

Figure 7. Comparison between the generalized self inelastic structurefactors derived from the neutron scattering experiments (blue line his-tograms), and from the ab-initio simulations (dashed red lines) for heavyalkaline earth hydrides. The one-phonon fundamental components of thelatter spectra have been also reported (as dotted green lines) to mark theend of the phonon density of states.

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ening of the H-DoPS TO bands might be the mark of thehydrogen anharmonic dynamics in LiH through a finitephonon life-time [11]. As for heavier alkaline metal hy-drides (i.e. the NaH-CsH series), our experimental deter-minations of the H-projected densities of phonon states(see Fig. 6) contained detailed information on the hydro-gen self-dynamics in such compounds, especially as re-gards its dependence on the cation atomic number andthe lattice constant. As we have already mentioned inSect. 1, there is no previous experimental study availableon ZH(E) in these systems (except a preliminary reporton NaH [9]); thus the present work fills a large gap inthe understanding of the H vibrational dynamics in al-kali metal hydrides. In Fig. 6 a detailed comparison be-tween IINS and ABINIT H-DoPS curves is shown: oneobserves a satisfactorily good agreement in the case ofKH, RbH and CsH. As for NaH, the comparison betweenexperiment and simulation is globally acceptable, butnot so good as for the other hydrides. For example, theposition of the first ZH(E) peak (due to the TO phononband) is not precisely reproduced by ABINIT. A clearlyremarkable feature is represented by the strong similari-ty of the H-projected densities of phonon states in thelast three AlkH: it suggests that KH, RbH and CsH couldbe gathered together in a sub-group of compoundsrather different from LiH [8,10], NaH being a sort of‘crossover’ alkali metal hydride. The effect of the experi-mental energy resolution has been checked and found ir-relevant in the present spectral range (50 meV<E<150meV). Together with the phonon energy calculations,ABINIT code has also provided reliable estimates of theAlkH lattice constants (see [46]), whose discrepanciesfrom the experimental values [13] are always lower than1%. Another interesting characteristic of the ABINIT da-ta is the lowering of both transverse and longitudinaloptical branches while the cation atomic number increas-es. This fact is very evident from the H-DoPS plotted inFig. 6. In addition, one can observe the behavior of thetransverse optical branches, which become globallysharper moving from NaH to CsH. However, some dis-persion in E is still present and clearly visible and thiscan be interpreted as the effect of a residual long-rangeinteraction between H ions. Our experimental determi-nations of the generalized self inelastic structure factorin orthorhombic alkaline earth hydrides (see Figs. 3 and7) contain detailed information on the hydrogen self-dy-namics in these compounds, even though in a less directform than in H-DoPS. As we have already mentioned inSect. 1, there was no previous high-resolution experi-mental study available on Σ(Q,E) in two of these systems(namely SrH2 and BaH2); thus the present measurements[23] fill a certain gap in the knowledge of the H vibra-tional dynamics in ionic hydrides. As for CaH2, the pre-sent estimate of Σ(Q,E) shows an excellent agreement

with the recent one from Morris et al. [21], providing afurther improvement of the spectral energy resolution.Looking at Fig. 3 one can immediately distinguish threemain spectral areas for all the HAEH2 patterns reported,if the small acoustic part at low energies (E<50 meV) isdisregarded. Choosing, for example, SrH2 as reference,one observes a three-peak zone from 67 meV to 95 meV(labeled “A”), then a second three-peak zone from 101meV to 136 meV (labeled “B”), and finally a large humpat E>137 meV (labeled “C”). Actually a remarkable fea-ture is represented by the strong similarity among thethree generalized self inelastic structure factors ofHAEH2: it suggests that even from the dynamical pointof view CaH2, SrH2 and BaH2 can be gathered together ina close group of compounds, unified by their commoncrystal structure in a way similar to what was found forthe heavy alkali metal hydrides KH, RbH and CsH. An-other interesting characteristic of the present phononspectral data is the softening of both “A” and “B” opticalbands while the cation atomic number increases, where“A” moves from the energy range (71-101) meV to (67-94) meV, while “B” from (111-141) meV to (102-133) meV.In addition, one can observe that “A” becomes globallysharper moving from CaH2 to BaH2. This effect presentin Σ(Q,E) has probably to be related to the flatness of thecorresponding phonon dispersion curves at the edge ofthe first Brillouin zone. On the contrary, “B” shows nosign of such a shrinking. In Fig. 7, a detailed comparisonbetween IINS and ABINIT Σ(Q,E) curves is also shownand one can easily observe an overall satisfactorilyagreement in all cases. However, for BaH2 the compari-son between experiment and simulation, though global-ly acceptable, does not result as good as for the othertwo hydrides. For example, the positions and the heightsof the second and third peak (at 66.5 meV and 68 meV,respectively) are not precisely reproduced by ABINIT,and, in addition, all the first three simulated peaks ex-hibit a certain width which reveals a slightly too largedispersion of the “A” optical phonon bands. Similar dif-ferences are also visible in the CaH2 simulated spectrum,but to a less severe extent. Once again, the effect of theexperimental energy resolution has been also checked,but found irrelevant in the plotted spectral range (50meV<E<175 meV). With the help of the ABINIT estimatesof phonon polarization vectors, it is possible to definitivelyconfirm the physical interpretation of the spectral branches“A” and “B” proposed for CaH2 in Ref. [21], i.e. the formerbeing caused by one type of H atom (H2) having an ap-proximately square pyramidal coordination (5 metalneighbor atoms), while the latter connected to anothertype of H (H1) with an almost tetragonal coordination (4metal neighbor atoms). Simulation data are reported inFig. 8. On the other hand, “C” comes out to be related onlyto multi-phonon excitations (as shown by the simulated

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one-phonon components reported in Fig. 7), and this iswhy it has not been considered in the present discussion.

Conclusion and perspectiveIn the present study we have reported incoherent inelas-tic neutron scattering spectra from alkali metal hydrides(LiH, NaH, KH, RbH and CsH) and orthorhombic alka-line earth hydrides (CaH2, SrH2 and BaH2) measured atT<20 K in the energy and momentum transfer ranges 3meV<E<500 meV and 2.8 Å-1<Q<16.5 Å-1.From the medium-energy region of these spectra (name-ly 50–150 meV, coinciding with the optical phononbands), we were able to extract accurate generalized selfinelastic structure factors and, in the case of rock-saltstructures (LiH-CsH), hydrogen-projected densities ofphonon states too.These experimental spectral functions were then com-pared to equivalent results obtained from ab-initio latticedynamics simulations, operated through the ABINITcode [40], and based on density functional theory andpseudo-potentials.The overall agreement between neutron and ab-initio da-ta turned out to be very good for the alkali metal hy-drides, especially impressive for the three heaviest com-pounds: KH, RbH and CsH. As for the comparison be-tween neutron and ab-initio data on orthorhombic alka-line earth hydrides, it came out to be satisfactory, even

though some discrepancies still appeared in the first op-tical phonon zone, especially in the case of barium hy-dride, where peak positions, heights and widths werenot perfectly reproduced by simulations. However, themost interesting result provided by the ABINIT simula-tions for this class of materials is probably the separationof the spectral contributions coming from the two non-equivalent H atoms in the hydride lattice. This gives a strong and quantitative support to the re-cent physical interpretation of the spectral features pro-posed by Morris et al. for CaH2 [21], and is easily extend-able to all the orthorhombic alkaline earth hydrides.All these findings prove that, at least for the simpleclass of binary ionic hydrides, a quantitative agreementbetween experimental and ab-initio data is possible, notonly for static (lattice parameters) and macroscopicquantities (bulk modulus, cohesive energy etc.), but alsofor the issue of the microscopic hydrogen dynamics.Thus incoherent inelastic neutron spectroscopy tech-nique has proved to be not only a reliable method forthe investigation of the H dynamics in metal hydrides[48], but also a stringent and demanding validation toolfor lattice dynamics simulations of these technologicallyrelevant materials.These conclusions pave the way for a broader investiga-tion of more complex compounds such as borohydridesand aluminohydrides.

Figure 8. One-phonon (fundamental) component of the generalized self inelastic structure factor for CaH2 derived from ab-initio simulations. Thecontributions from the two non-equivalent hydrogen atoms are plotted separately: dotted red line for H2, and dash-dotted green line from H1. The sum ofthese two contributions is also reported (full blue line) and vertically shifted for graphical reasons. Symbols “A” and “B” are explained in the main text.

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AcknowledgementsThe authors are deeply indebted with Dr. A. J. Ramirez-Cuesta (Rutherford Appleton Laboratory, Great Britain)and Prof. G. Barrera (Universidad Nacional de la Patago-nia SJB, Argentina), and with Dr. G. Auffermann (Max-Planck Institut, Germany) for their crucial scientific con-tributions in the ab-initio simulations and the samplepreparation, respectively. In addition, the skillful techni-cal help of the ISIS User Support Group is gratefully ac-knowledged. This work has been partially supported byEnte Cassa di Risparmio di Firenze through the Firenze Hy-drolab project.

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(Academic, New York, 1968).3. E. Zintl and A. Harder, Z. Phys. Chem. B 14, 265 (1931).4. V. I. Zinenko and A. S. Fedorov, Sov. Phys.—Solid State 36, 742 (1994).5. E. Haque and A. K. M. A. Islam, Phys. Status Solidi b 158, 457 (1990);

A. K. M. A. Islam, Phys. Status Solidi b 180, 9 (1993).6. J. M. Besson, G. Weill, G. Hamel, R. J. Nelmes, J. S. Loveday, and S.

Hull, Phys. Rev. B 45, 2613 (1992) and references therein.7. A. C. Ho, R. C. Hanson, and A. Chizmeshya, Phys. Rev. B 55, 14818

(1997) and references therein.8. M. G. Zemlianov, E. G. Brovman, N. A. Chernoplekov, and Yu. L.

Shitikov Inelastic Scattering of Neutrons vol. II (Vienna, IAEA, 1965) p.431; J. L. Verble, J. L. Warren, and J. L. Yarnell, Phys. Rev. 168, 980 (1968).

9. A. D. B. Woods, B. N. Brockhouse, M. Sakamoto, and R. N. Sinclair,Inelastic Scattering of Neutrons in Liquids and Solids (IAEA, Vienna,1961) p. 487 (contains raw neutron spectra from LiH and NaH).

10. W. Dyck and H. Jex, J. Phys. C: Solid State Phys. 14, 4193 (1981).11. J. Boronat, C. Cazorla, D. Colognesi, and M. Zoppi, Phys. Rev. B 69,

174302 (2004).12. G. Auffermann, G. D. Barrera, D. Colognesi, G. Corradi, A. J. Ramirez-

Cuesta, and M. Zoppi, J. Phys.: Condens. Matter 16, 5731 (2004).13. R. W. G. Wyckoff, Crystal Structures, vol. I (Interscience, New York,

(1963).14. G. S. Smith, Q. C. Johnson, D. K. Smith, D. E. Cox, R. L. Snyder, R.-S.

Zhou, and A. Zalkin, Solid State Commun. 67, 491 (1988).15. E. Zintl and A. Harder, Z. Elektrochem. 41, 5 (1935).16. J. Bergsma and B. O. Loopstra, Acta Cryst. 15, 92 (1962); A. F.

Andresen, A. J. Maeland, D. Slotfeldt-Ellingsen, J. Solid State Chem.20, 93 (1977).

17. N. Brese, M. O’Keeffe, and R. Von Dreele, J. Solid State Chem. 88, 571(1990).

18. W. Bronger, S. Chi-Chien, and P. Müller, Z. Anorg. Allg. Chem. 545, 69(1987).

19. T. Sichla and H. Jacobs, Eur. J. Solid State Inorg. Chem. 33, 453 (1996).20. G. J. Snyder, H. Borrmann, and A. Simon, Z. Kristallogr. 209, 458 (1994).21. P. Morris, D. K. Ross, S. Ivanov, D. R. Weaver, and O. Serot, J. Alloys

Comp. 363, 85 (2004).22. A. J. Maeland, J. Chem. Phys. 52, 3952 (1969).23. D. Colognesi, G. D. Barrera, A. J. Ramirez-Cuesta, and M. Zoppi, in

press on J. Alloys Compd. (2006).24. A. El Gridani and M. El Mouhtadi, Chem. Phys. 252, 1 (2000).25. A. El Gridani and M. El Mouhtadi, J. Mol. Struct. (Theochem.) 532, 183

(2000).

26. A. El Gridani, R. Drissi El Bouzaidi, and M. El Mouhtadi, J. Mol.Struct. (Theochem.) 531, 193 (2000).

27. A. El Gridani, R. Drissi El Bouzaidi, and M. El Mouhtadi, J. Mol.Struct. (Theochem.) 577, 161 (2002).

28. H. Smithson, C. A. Marianetti, D. Morgan, A. Van den Ven, A. Predith,and G. Ceder, Phys. Rev. B 66, 144107 (2002).

29. D. Colognesi, M. Celli, F. Cilloco, R. J. Newport, S. F. Parker, V. Rossi-Albertini, F. Sacchetti, J. Tomkinson, M. Zoppi, Appl. Phys. A 74[Suppl. 1], 64 (2002).

30. H. H. Paalman and C. J. Pings, J. Appl. Phys. 33, 2635 (1962).31. V. F. Sears, Neutron News 3, 29 (1992).32. A. K. Agrawal, Phys. Rev. A 4, 1560 (1971); V. F. Sears, Adv. Phys. 24, 1

(1975).33. M. M. Bredov, B. A. Kotov, N. M. Okuneva, V. S. Oskotskii, and A. L.

Shakh-Budagov, Sov. Phys. Solid State 9, 214 (1967).34. J. Dawidowski, F. J. Bermejo, and J. R. Granada, Phys. Rev. B 58, 706

(1998).35. D. Colognesi, C. Andreani, and E. Degiorgi, J. Neutron Res. 11, 123

(2003).36. P. S. Goyal, J. Penfold, and J. Tomkinson, The influence of multiple

scattering on the inelastic neutron scattering spectra of molecularvibrations, RAL 86-070, unpublished, 1986.

37. R. Baddour-Hadjean, F. Fillaux, N. Floquet, S. Belushkin, I. Natkaniec, L.Desgranges, and D. Grebille, Chem. Phys. 197, 81 (1995).

38. A. J. Ramirez-Cuesta, Comp. Phys. Commun. 157, 226 (2004).39. V. F. Turchin, Slow Neutrons (Israel Program for Scientific

Translations, Jerusalem, 1965).40. X. Gonze, J.-M. Beuken, R. Caracas, F. Detraux, M. Fuchs, G.-M.

Rignanese, L. Sindiç, M. Verstraete, G. Zerah, F. Jollet, M. Torrent, A.Roy, M. Mikami, Ph. Ghosez, J.-Y. Raty, and D. C. Allan, Comp. Mat.Sc. 25, 478 (2002).

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42. S. Goedecker, M. Teter, and J. Hutter, Phys. Rev. B 54, 1703 (1996); J. P.Perdew, K. Burke, and M. Ernzerhof, Phys. Rev. Lett. 77, 3865 (1996).

43. N. Troullier and J. L. Martins, Phys. Rev. B 43, 1993 (1991).44. C. Hartwigsen, S. Goedecker, and J. Hutter, Phys. Rev. B 58, 3641

(1998).45. J. P. Perdew, K. Burke, and M. Ernzerhof, Phys. Rev. Lett. 77, 3865

(1996).46. G. D. Barrera, D. Colognesi, P. C. H. Mitchell, and A. J. Ramirez-

Cuesta, Chem. Phys. 317, 119 (2005).47. X. Gonze and C. Lee, Phys. Rev. B 55, 10355 (1997).48. D. K. Ross in H. Wipf (Ed.), Hydrogen in Metals, vol. III (Springer,

Berlin, 1997) p. 153.

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AbstractNeutron resonance capture analysis (NRCA) is a non-de-structive method for analysing the bulk composition ofmaterials and objects. It has been developed at the GELI-NA facility of the Institute for Reference Materials andMeasurements (IRMM) in Geel (B) as a joint project withthe Delft University of Technology. In this paper somefeatures of NRCA are discussed on the basis of resultsobtained in the field of archaeology.

IntroductionNeutrons are used in various ways to analyse the ele-mental compositions, crystallographic structures andtexture of archaeological and art objects, and for radiog-raphy and imaging of objects. One of the analyticalmethods is based on the occurrence of resonances inneutron capture cross sections. Since resonances occur atneutron energies specific for each nuclide, they can beused to recognize elements. In addition, the areas of res-onance peaks provide information about elementalamounts. Resonance capture can be observed easily by

detecting the prompt gamma rays emitted after neutroncapture. The energies of captured neutrons can be deter-mined with the time-of-flight (TOF) method with neu-trons travelling a known distance. This method requiresa pulsed neutron source, which provides the start pulsefor the TOF measurement. The stop pulse is generatedby detection of the prompt gamma rays. It is not neces-sary to know the energy of the prompt gamma rays witha high resolution. Therefore, large scintillation detectors,not necessary with good energy resolution, but with agood time resolution can be used.In addition, gamma rays can be accepted over a wide en-ergy range, typically from about 300 KeV up to the neu-tron binding energy. Together with the fact that captureevents are followed by several gamma-ray transitions incascade, it is possible to obtain large detection efficien-cies for capture events. Resonance capture as a functionof neutron energy is the basis of the analytical method“Neutron Resonance Capture Analysis (NRCA)”.NRCA has been explored at the GELINA facility of theIRMM in Geel (B) in a joint project with the Delft Univer-

Neutron-resonance capture as a tool to analysethe internal compositions of objects non-destructivelyH. Postma,Delft University of Technology, Mekelweg 15, 2629 JB Delft, the Netherlands

P. Schillebeeckx, EC-JRC IRMM, Retieseweg, Geel, Belgium

Figure 1. A schematic drawing showing the TOF system at the GELINA facility.

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sity of Technology in the Netherlands with applicationsin archaeology, the nuclear field and for the characterisa-tion of reference materials. In this paper mainly the use ofNRCA for archaeological and art objects is considered.

Experimental facilityThe basic element of the GELINA facility is a linear ac-celerator producing very short pulses of electrons withenergies from 70 to 150 MeV, with a repetition rate up to800 Hz and a maximum power of 10 kW. Stopping theseelectrons in uranium produces Bremsstrahlung, which inturn generates neutrons by photonuclear and photofis-sion processes. Moderation in two water containing Be-tanks close to the uranium target produces a ´´white´´spectrum of neutrons. Above about 1 eV the neutron fluxis in first approximation proportional with the inverse ofneutron energy. Details of the GELINA facility and ageneral review of the neutron-nuclear research carriedout at this facility are discussed in another contributionto this issue [1]. Figure 1 shows a schematic presentationof the linac, neutron production target and TOF system. In the more recent NRCA experiments two C6D6-basedliquid scintillation detectors (7.5 cm thick and 10 cm indiameter) are used as capture detectors. They are placedat a distance of about 7 cm from the centre line of theneutron beam. The objects can be positioned at a distanceof about 15 or 30 m from the pulsed neutron source.The beam diameter at the sample position is about 7.5cm. Figure 2 shows a set-up with two C6D6 detectorsviewing from opposite sides a prehistoric bronze axis.Shielding such detectors against neutrons scattered from

the object is not necessary because of their very low neu-tron sensitivity. The only neutron-related background isdue to capture in the surrounding materials producing agamma-ray background.Therefore, it is important to keep material away from

these detectors as much as possible. Another advantageof C6D6 is its short decay time, resulting in a time resolu-tion better than 1 ns. In addition, their response is wellunderstood and they have sufficient energy resolution tocontrol the selected energy range (0.3 to 10 MeV).Normally a cadmium filter (0.75 mm thick) is placed ear-ly in the beam to remove so-called overlap neutrons be-low 0.7 eV. To avoid overloading of the detectors byBremsstrahlung flashes, filters of lead (1.5 cm thick), orbismuth (1.5 cm thick) and lately also sulphur (5.0 cmthick) are used.

Features of NRCAIn figure 3 an example of a TOF capture spectrum with aprehistoric bronze axe obtained at the 29 m measurementstation is shown. The spectrum shows the detector effi-ciency of the capture detection system as a function ofthe TOF of the neutron creating the capture event. (NB:this is not a gamma-ray spectrum as some people tend tothink.) The time-of-flight of the neutron, Tn, can be con-verted to the neutron energy, En, using the relation:

(1)

where L is the flight path length and mn the neutronmass. At the top of the figure the energy scale is indicat-ed. Some of the most important resonances are markedin this figure, for copper at 230, 578, and 994 eV, and for

tin at 38.8 and 111 eV. Other marked peaks are from sil-ver and antimony. This spectrum illustrates that manysharp resonance peaks occur which can be distinguishedeven in the keV region. This is due to the high-energyresolution of the GELINA facility.

E mLTn n

n=

⎛

⎝⎜

⎞

⎠⎟

12

2

Figure 2. Two C6D6 detectors opposite to each other with respect to theobject, located at the centre of the neutron beam. The object is asocketed bronze axe.

Figure 3. Example of a TOF-capture spectrum obtained for a prehistoricbronze axe with flight path of 28.615 m. Some resonance peaks areindicated.

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The spectrum in figure 3 also reveals that often TOF re-gions for minor or trace elements can be selected suchthat their detection is not hampered by the presence ofother elements. For instance the minor elements Sb andAg in bronze objects have resonances at 21.4 and 6.22 eV,respectively 5.19 eV (see figure 3) which are not influ-enced by the response due to the presence of resonancesof other components, notably the main elements copperand tin. Since in addition the detection efficiency at thelower energies is very large minor components like Sband Ag can be detected in the ppm range.A qualitative analysis based on recognizing resonancescan be done on-line during data acquisition and may al-ready give a quick impression about the elemental com-position. For a quantitative analysis the areas under res-onance peaks must be determined. Many of the peaks ina spectrum like the one in figure 3 are sufficiently wellseparated to determine their areas by summing over thechannels and subtracting the background determinedfrom adjacent regions. For a better accuracy peak fittingis necessary. This is certainly the case for closely lying,partly overlapping peaks. Resonance peaks may showon their high energy sides rather broad structures oreven a bump due to neutron scattering in the object fol-lowed by neutron capture. In fact the possibility of po-tentional and resonance scattering requires a detailedanalysis. Fitting can be done applying a resonanceshape analysis using codes such as REFIT developed byMoxon [2].This code was primarily developed to determine reso-nance parameters from TOF-spectra of well-charac-terised samples of simpler forms. The code determinesthe full response of the detector system starting fromfirst principles and accounts for the self-shielding andmultiple scattering effect, the Doppler broadening, thetime resolution of the TOF-facility, and other effects suchas the neutron sensitivity of the detector system. SinceNRCA is not intended to determine resonance parame-

ters the simpler approach of parametric fitting of reso-nance peaks has mostly been used. This is demonstratedin figure 4 for the 47-eV antimony resonance with someneighbouring smaller peaks. The 47-eV peak is fitted as aGaussian broadened Lorentz line, the other peaks andthe high energy shoulder of the antimony peak, due toscattering plus capture, are fitted with Gaussian func-tions. This approach has shown to work satisfactorily. Inthe case of saturated resonance peaks more complicatedline shapes should be taken into account.There are two ways to derive the composition of an ob-ject. Absolute amounts of elements can in principle bedetermined if the neutron flux, the detection efficiencyand other details determining the time resolution andpeak shapes are well known. This approach using theREFIT code has been applied successfully in Ref. [3] forthe determination of the amount of Gd in U-samples andfor the determination of impurities in reference materi-als. Another way is to determine relative amounts of ele-ments with respect to a major element on the basis of ra-tios of peak areas and compare them with those fromcalibration samples. In the case of bronzes relativeamounts of the elements are determined with respect tocopper. The weight ratio of two elements (I and II) canbe determined with:

(2)W(I)W(II)

CA(I,E )

A(II,E )I

II= ⋅

Figure 4. A parametric fit of a part of the TOF spectrum between 42 and60 eV.

Figure 5. The ratio of the 230 and 578 eV peak areas as a function ofthickness in gr.Cu/cm2 used to determine the thickness of a fragment of abronze cauldron.

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where A(j,Ej) denotes the observed area of the resonanceat energy Ej for elements j. The factor C can be deter-mined from a calibration sample with a known ratio ofthe two elements I and II.There is an important aspect to be taken into account inthe quantitative analysis; namely the self-shielding ef-fect of resonances. That is, the number of neutrons atresonance energies diminish during passage of thebeam through the sample by resonance capture andscattering. Especially for strong resonances self-shield-ing is an important phenomenon. The effect of self-shielding can be calculated as a function of penetrationdepth using the Doppler broadened total resonancecross section. The two resonance areas in eq.2 must becorrected for self-shielding, if necessary in a recurrentmanner. Of course this also holds for calibration sam-ples. This self-shielding effect might be seen as a draw-back, however, it can be turned into an advantage. Dueto self-shielding the area ratio of two resonances of dif-ferent strengths varies with sample thickness. As ademonstration figure 5 shows the ratio of the areas ofthe 230- and 578-eV copper resonances. This ratio variesconsiderably with thickness. It has been used to esti-mate the Cu thickness of a fragment from a bronze caul-

dron (7th cBC and excavated in Satricum) as a check onthe correctness of the analysis [4].If elements show up with several resonances in a capturespectrum, the weight ratio can be determined on the ba-sis of a number of resonance pairs. For bronzes theSn/Cu weight ratio is obtained from six pairs of reso-nances using three for copper (at 230, 650 and 994 eV)and two for tin (38.8 and 111 eV). Figure 6 shows the result in case of an Etruscan votivewith the data uncorrected and corrected for self-shielding[5]. The resulting values of the Sn/Cu weight ratio are inexcellent mutual agreement after applying the self-shield-ing correction. Inconsistent weight ratios indicate an in-homogeneous composition. The occurrence of resonancesof different strengths is an additional powerful feature ofNRCA. Strong resonances are very suitable for detectingminor and trace elements often in the ppm range. Theweaker resonances are perfect to investigate major ele-mental components of an object. If a strong resonance of amajor element is investigated, it provides information ofthis element only in a surface layer of the object. With the excellent time resolution of the GELINA facilityhigh-energy resonances can be included in the analyses.The upper energy limit depends on the complexity of

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Figure 8. Two bronze statuettes, one is a genuine Etruscan artefact and theother a later imitation (probably from the Renaissance period).

Figure 6. The Sn/Cu weight ratio determined for 6 pairs of resonancesuncorrected and corrected for self-shielding for an Etruscan statuette.

Figure 7. Three Cu-resonances and one Pb-resonance in the region of3250–3650 eV used to determine the Pb/Cu weight ratio of an Etruscanvotive.

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the TOF spectrum and thus on the kind of material. Formaterials like marble resonances up to about 30 keV canbe used [6]. Since capture spectra of ancient bronze ob-jects are often complicated mainly due to the minors As,Sb and Ag, the upper limit is at about 10 keV. Thatmeans that lead, which has its lowest useful resonancesat about 3 keV, can be included in the analysis. Lead isan important element in bronze objects since it is oftenadded in considerable quantities. In bronze objects leadcan be detected with concentrations above about 1 %. Figure 7 shows a section of the TOF spectrum between3250 and 3650 eV showing the 3357-eV resonance of206Pb and three Cu-resonances at 3310, 3503 and 3588 eV.Since these four resonances are weak the Pb/Cu weightratio can be obtained with at most small self-shieldingcorrections.

Short review of applicationsNRCA has been applied to a considerable number ofartefacts, so far mainly bronze objects. A series of Etr-uscan statuettes from a collection originally owned byearl Corazzi of Cortona (I), but bought by the Dutchgovernment in 1826 and now at the National Museum ofAntiquities in Leiden (NL) was studied. It turned outthat it was possible to distinguish suspected fakes fromgenuine statuettes on the basis of the elemental composi-tions [5]. The conclusion was based on the observationthat in some of these statuettes several per cents of zincoccur. With the smelting technique available to the Etr-uscan smiths, not more than a fraction of a per cent ofzinc can enter into bronze. Two Etruscan objects, onegenuine and one false, are shown in figure 8.A number of NRCA measurements at GELINA con-cerned single objects. One of them was an antique com-memorative plaque from the West-African countryBenin, of which the originality was questioned. The de-termination of the composition was helpful and suggest-ed that it is indeed genuine and by comparison datableto the period of 1725 to 1897 [7]. A recent project con-cerns the elemental compositions of bronze prehistoricaxes from north-west Europe. This may be helpful in un-derstanding production methods, trade relations in thispart of Europe and the usage of these axes. For exampleone type of axe has such thin walls that it is unsuitablefor cutting. It is suggested that it may have been used forceremonial purposes. There are remarkable differencesin the compositions of prehistoric axes, which might berelated to differences in local techniques and availabilityof metals. There are other fields in which NRCA can be applied.One concerns the study of the "poison" Gd in nuclear fu-el material. NRCA can be used to detect other isotopesproduced in nuclear reactor processes and for the char-acterisation of reference material [3].

ConclusionThe above examples show that even in a restricted fieldlike bronze artefacts a lot of interesting results can be ob-tained. Probable even more so if NRCA is combined withresults from other neutron based techniques as PGAA andTOF neutron diffraction, and the imaging method to bedeveloped in the Ancient Charm project. The latter is im-portant for inhomogeneous objects. A comparison of NRCA and PGAA as elemental analysistechniques is discussed in Ref. [8].In conclusion the following statements can be made:• NRCA is fully non-destructive, it is not necessary to take

samples from an object or to remove some of the patina,• The residual activation is negligible,• The existence of weak and strong resonances provides

an interesting flexibility for the analysis, and• The high penetrability of neutrons is an important fea-

ture of neutron based analytical techniques.

AcknowledgementsWe like to sincerely thank the National Museum of An-tiquities in Leiden (NL) for the loan of several bronzeartefacts.

References1. W. Mondelaers and P. Schillebeeckx, “GELINA, a neutron time-of-flight

facility for high-resolution neutron data measurement”, in this issue.2. M. Moxon, “REFIT2: A least Squares Fitting Program for Resonance

Analysis of neutron Transmission and capture Data,” NEA-0914/02(1989)

3. P. Schillebeeckx, A. Borella, A. Moens, R. Wynants, M. Moxon, H.Postma, C.W.E. Van Eijk, "The use of Neutron Resonance CaptureAnalysis to determine the elemental and isotopic composition ofnuclear material", Proceedings of the 27th Annual Symposium onSafeguards and Nuclear Material Management, London, UnitedKingdom, May 10-12, (2005), Proc. ISBN 95-894-9626-6.

4. H. Postma, M. Blaauw, P. Schillebeeckx, G. Lobo, R. Halbertsma andA.J. Nijboer, "Non-destructive elemental analysis of copper-alloyartefacts with epithermal neutron-resonance capture", Czech. J. ofPhysics 53 (2003), A233-249.

5. H. Postma, P. Schillebeeckx and R. Halbertsma, "Neutron ResonanceCapture Analysis of some genuine and fake Etruscan Copper-alloystatuettes", Archaeometry 46 (4) (2004), 635-646.

6. R.C. Perego, H. Postma, M. Blaauw, P.Schillebeeckx, A. Borella,"Neutron Resonance Capture Analysis: improvements of thetechnique for resonances above 3 keV and new applications",Proceedings MTAA11 conference, Univ. of Sussex, Guildford (UK) 20-24 June 2004, to be published in J. of Radioanal. Nucl. Chem.

7. M. Blaauw, H. Postma and P. Mutti, "An attempt to date an antiqueBenin bronze using neutron resonance capture analysis", AppliedRadiation and Isotopes 62 (2005) 429-433.

8. H. Postma and P. Schillebeeckx, "Non-destructive analysis of objectsusing neutron resonance capture", J. of Radioanal. Nucl. Chem. 265(2005) 297-302.

19


AbstractAccurate neutron data are required for the assessment ofsafety aspects of nuclear power installations or for thedesign of new innovative concepts like nuclear wastetransmutation or accelerator driven systems. For themeasurement of such data in the resonance region an ex-tremely good energy resolution is required, only achiev-able using a pulsed white-spectrum neutron source incombination with time-of-flight measurements. The GeelElectron LINear Accelerator Facility (GELINA) at the In-stitute for Reference Materials and Measurements (IR-MM) of the European Commission’s Directorate-GeneralJoint Research Centre (JRC) is especially designed forsuch purposes. Within the framework of the EURATOM‘Transnational Access to Large Infrastructure’ pro-gramme, JRC-IRMM is able to offer, via the NUDAMEproject, beam time to external users from EU membercountries and associated states.

IntroductionThe development and improvement of a comprehensivecross section database is essential for many areas of re-search and technology. For nuclear power production,neutron-induced reactions are definitely the most impor-tant interactions. Many interaction types may occur innumerous isotopes. A precise knowledge of neutroncross sections, over a broad energy range, is of a greatimportance for a proper account of reaction rates and thedetailed neutron flux distributions in many nuclear ap-plications. They are vital when evaluating the safety andrisks related to the operation of nuclear power plantsand to nuclear waste management. Also the develop-ment of innovative systems like accelerator-driven trans-mutation systems or new concepts of nuclear power pro-duction must rely on complete, accurate and consistentneutron data libraries. Reducing uncertainties in theneutron cross section data can result in an enhancedsafety and efficiency of present and future nuclear pow-er systems [1]. Accurate neutron cross sections play acrucial role not only for nuclear power, but also in manyother disciplines such as astrophysics, medicine, and se-curity [2, 3, 4]. In the energy interval from thermal neutron energies to afew MeV the neutron cross sections have a resonance-type energy dependence and large differences exist be-tween the neighbouring isotopes. In the resonance re-

gion, two energy domains need to be distinguished:• the resolved resonance region where the neutron

cross sections reveal a complicated resonancestructure,

• the unresolved resonance region, where themeasured width of the resonances is larger than theresonance spacing, and the resonances appear to beoverlapping.

The resonance structure, which largely differs from iso-tope to isotope, cannot be predicted or reproduced bymodels. Therefore, experiments with high energy resolu-tion over the whole spectrum are required. These mea-surements allow extraction of the resonance parametersthat describe the cross sections in detail. Accurate reso-nance parameters are calculated by using the techniqueof resonance shape analysis [5]. The required measure-ment accuracy can only be obtained at neutron Time-Of-Flight (TOF) facilities especially designed for very high-energy resolution measurements [6]. In a TOF facility, the neutrons used for the neutron crosssection measurements are produced by the impact of ashort pulse of high-energy particles on a neutron-pro-

GELINA, a neutron time-of-flight facility for high-resolution neutron data measurementsW. Mondelaers and P. Schillebeeckx, EC-JRC- IRMM, Retieseweg 111, Geel, Belgium

Figure 1. Aerial view of the GELINA time-of-flight facility

RESEARCH INFRASTRUCTURES


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ducing target. The impinging particles can be:• electrons that create neutrons via the production of

bremsstrahlung and consecutive photonuclearreactions, or

• protons that generate neutrons via the spallationreaction.

The TOF-facility GELINAThe TOF-facility GELINA has been especially designedand built for high-resolution cross section measure-ments. It is a multi-user facility, serving up to 12 differ-ent experiments simultaneously, and providing a pulsedwhite neutron source, with a neutron energy range be-tween 1 meV and 20 MeV. The installation is operated inshift work on a 24 hours/day basis, for about 100 h perweek. Figure 1 shows an aerial view of the GELINA fa-cility. Neutrons are produced in bunches of less than 1 nsduration, at repetition rates up to 800 Hz. The total neu-tron flux of the target is 3.4 x 1013 neutrons/s. This fluxis rather low compared to the neutron facilities wherescattering and diffraction are used as a tool for structureand dynamics analysis, applied in many scientific andtechnological domains. Such investigations require highfluxes of neutrons at very long wavelengths. For thestudy of the basic interaction mechanism of neutronswith nuclei (total, capture, fission, inelastic scattering,and charged-particle production cross section measure-ments) energy resolution in the resonance region is themost important design criterion.Improvement of the energy resolution, while maintain-ing good neutron source strength has been a continuing

effort at GELINA [7, 8, 9]. Among the pulsed whitespectrum neutron sources available in the world, GELI-NA is the one with the best energy resolution. The re-sulting excellent neutron energy resolution is made pos-sible by a combination of four specially designed anddistinct units: • a linear electron accelerator delivering a pulsed

electron beam, • a post-acceleration relativistic-energy compression

magnet system, • a rotary mercury-cooled uranium target, • 12 different flight paths, ranging from 10 m up to

400 m.

Linear electron acceleratorA schematic overview of the electron accelerator is givenin figure 2. The pulsed electron beam is generated in aninjector with a Pierce-type triode gun. The injected elec-tron pulses have a duration of 10 ns and a very highpeak current of 12 A. The linear accelerator consists ofthree S-band accelerator sections operating at a frequen-cy of 2999 MHz. The electrons are accelerated along theaxis of the sections by the longitudinal electric field of anelectromagnetic wave travelling synchronously with thehighly charged electron pulses. The accelerating wavesin the sections are produced with three pulsed high-power klystrons. The klystrons are powered with line-type pulse power modulators. They deliver to each sec-tion 25 MW peak power wave trains of 2 µs at a maxi-mum repetition rate of 800 Hz. The duration of a wavetrain is longer than the so-called filling time of an accel-

Figure 2. Scheme of the GELINA linear electron accelerator


21


erator section (the filling time is the time required to filla section completely with electromagnetic power – forGELINA the filling time is typically 1,2 µs). In this wayall cavities from an accelerator section can be filled withelectromagnetic power before an electron pulse is inject-ed. The energy of the electrons in a pulse leaving the ac-celerator varies linearly from 140 MeV at the start of thepulse to 70 MeV at the end of the pulse. This is becausethe first electrons of a pulse ‘see’ the full acceleratingfield during their travel along the accelerator, all cavitiesbeing filled with the maximum power. Each electron ex-tracts power from the wave. The electron pulse is soshort that there is not enough time to replenish the con-sumed power in the cavities during the duration of theelectron pulse. The following electrons in a pulse experi-

ence a lower accelerating field than their forerunners. Asa result of this so-called transient beam loading, the en-ergy of the electrons is decreasing monotonically, fromthe beginning to the end of the pulse. This intrinsic fea-ture of time-energy relationship during the electronpulse is now fully exploited to compress further the elec-tron pulse lengths in the compression magnet installedat the end of the accelerator [8].

Compression magnetBefore hitting the neutron-producing rotary target, theelectrons make a ‘looping’ in a specially designed 360°compression magnet. This magnet has a diameter of 3 mand a weight of 50 tons. It consists of five magnetic sec-tors with zero gradient fields and is designed to accept

Figure 4. Gelina target hall Figure 6. Neutron-producing target with peripheral equipment

Figure 3. Principle of post-acceleration pulse compression


22


the 50% electron energy spread in the beam of the accel-erator. The operational principle of the relativistic post-acceleration compression magnet is shown in figure 3.The bending radius of an electron in a magnet is propor-tional with its energy. Therefore, the first highest-energyelectrons in a pulse will follow a longer trajectory thanthe later ones. Since all electrons have a speed close tothe velocity of light, this results in a delayed arrival ofthe leading edge of the pulse at the exit of the magnet ascompared with the arrival of the trailing edge. The mag-net is designed such that all electrons of a 10 ns pulse,entering the magnet, will leave the compression magnetwithin a time bin of 1 ns. The peak current rises by thischarge conserving compression from originally 12 A toabout 120 A at the exit of the magnet. Figure 4 shows aphoto of the target hall, in which the position of the com-pression magnet is shown, with respect to the neutron-producing target.

Neutron-producing targetAfter the compression magnet the high-energy electronsimpinge on a rotating neutron-producing target [10]. Therotary target consists of a U-Mo alloy with 10wt% of Mo,cooled with liquid mercury and sealed in stainless steel.The neutron target, designed for optimum neutron pro-duction, has to withstand the full electron beam power(10 kW) almost completely dissipated in the target. Alay-out of the target is shown in figure 5. The electronsare decelerated and produce high-energy photons viathe Bremsstrahlung process. These photons may interactwith target nuclei and produce neutrons via (γ,n) and to

a much lesser extent by (γ,f) reactions. Uranium is cho-sen as target material because it favours the productionof photons in the Bremsstrahlung process and neutronsby photon-induced nuclear reactions. Above ~30 MeVelectron energy, the neutron production rate is nearlyproportional to the electron beam power. The use of ura-nium increases the total neutron yield by a factor ~2compared with another high-Z target, such as tantalum.From a thick uranium target roughly 6 neutrons areemitted per 100 electrons of 100 MeV. The power densityin the body, deposited by the electron beam may reach10 kW/cm3. Therefore the target is rotating in the beam.Mercury is chosen as a coolant, mainly to avoid neutronmoderation.The target delivers an average neutron intensity of 3.4 x1013 neutrons/s. In order to have a significant numberof neutrons in the energy range below 100 keV, twolight-water moderators are placed above and below theexisting target. The partially moderated neutrons havean approximate 1/E energy dependence plus aMaxwellian peak at thermal energy. Two flux set-ups areavailable: one optimised for energies below 500 keV byusing neutrons coming from the moderators and onewith fast neutrons emerging directly from the uranium.Based on the required energy range in a particular mea-surement station, shadow bars are properly placed be-tween the source and the flight path to shield unwantedneutrons. Further tailoring of the spectral shape is donewith movable filters. Figure 6 shows a photo of the rotat-ing target, collimators and shadow bars and the neutronshutters, leading to the flight paths.The present rotary

Figure 5. Scheme of neutron-producing target


23


target has been designed taking into account the need tothe limit the target-related contribution to the neutronenergy resolution. A project has been launched in orderto improve the accuracy of the high-resolution neutroncross-section measurements by designing a new targetconfiguration. A compact stationary target has been de-signed, which can reduce further the target-related inac-curacy, while preserving, and even enhancing the time-averaged neutron flux in all relevant neutron energyranges [9, 11].Figure 7 shows the absolute neutron flux of the moderat-ed spectrum that was measured in the energy rangefrom 25 meV to 200 keV by Borella et al. [12]. The resultsare compared with MCNP4C3 Monte Carlo calculationsperformed by Flaska et al. [9]. Figure 8 shows the com-parison of similar calculations with the absolute neutronflux of the unmoderated spectrum in the energy rangefrom 200 keV to 20 MeV, as measured by Mihaelescu etal. [13].

Neutron flight paths and measurement stationsIn order to apply the TOF technique, 12 flight-paths areinstalled in a star-like configuration around the neutronproduction target, schematically shown on the scheme infigure 9. The flight tubes are under vacuum, they have adiameter of 50 cm and their lengths range up to 400 m.Several measurement stations are installed at differentdistances (with nominal distances of 10, 30, 50, 60, 100,200, 300 and 400m) along the flight paths. These experi-mental stations are equipped with a wide variety of so-phisticated detectors, and data acquisition and analysis

systems, especially designed for neutron-induced totaland partial cross-section measurements with an excep-tional precision and energy resolving power. Modern de-tection techniques such as advanced HPGe Compton-suppressed detectors and data acquisition systems basedon fast signal digitisers are currently implemented.Many types of neutron cross section measurements arepossible. There are neutron measurement set-ups fortransmission experiments, capture, fission, elastic andinelastic cross sections, and flux measurements. Transmission measurements can be performed at a 25m,50m, 100m, 200m and 400m flight path using Li-glass de-tectors, plastic scintillators or NE213 scintillators. Tostudy the Doppler broadening one of the transmissionmeasurement stations is equipped with a cryostat, whichis able to cool the samples down to 10K. Fission crosssection measurements are performed at a 8m and 30 mstation using Frisch gridded ionisation chambers andsurface barrier detectors. These measurement stationsare also used to study (n,p) and (n,α) reactions. Inelasticscattering reactions are studied at a 30m or 200m stationusing HPGe-detectors. Capture measurement systems,using C6D6 scintillators or HPGe detectors, are availableat a 15m, 30m and 60m flight path.

Transnational Access via NUDAMEBesides the GELINA facility, the JRC-IRMM is alsoequipped with a Van de Graaff (VdG) facility. At theVdG quasi mono-energetic beams of neutrons are pro-duced in the energy range up to 24 MeV, using differentcharged-particle induced reactions. The high-resolution

Figure 8. Absolute neutron flux per unit lethargy of the unmoderatedneutron spectrum at 200 m and GELINA operating at 800 Hz.

Figure 7. Absolute neutron flux per unit lethargy of the moderatedneutron spectrum at 10 m and GELINA operating at 40 Hz.


24


measurements at GELINA can be complemented bymeasurements at the VdG, especially in the MeV neu-tron energy domain where the resonance structure of thecross-sections is averaged out. The VdG is a 7 MV elec-trostatic accelerator for the production of continuousand pulsed proton-, deuteron- and helium ion beams.Ion beams can be produced with a current of up to 60 µAin DC mode and up to 5 µA in pulsed mode. The pulserepetition rates are 2.5, 1.25 or 0.625 MHz. The energy ofthe mono-energetic neutrons is defined by using lithium,deuterium or tritium targets and choosing appropriateemission angles. Depending on the neutron energy up to108 neutrons/s can be obtained.Due to the combination of the GELINA white neutronTOF-facility and the quasi mono-energetic neutronsource at the VdG, the Reference Laboratory for Neu-tron Measurements at IRMM is one of the few laborato-ries in the world which is capable of producing the re-quired accuracy of neutron data over a wide energyrange from a few meV to about 24 MeV. These uniqueresearch capabilities offered at the two accelerators arean excellent opportunity for transnational collabora-tions in the field of transmutation research and innova-tive nuclear energy systems. To facilitate the access tothe facilities for outside users, a project ‘NUclear DAtaMEasurements at IRMM’ (NUDAME) has beenlaunched within the framework of the EuratomTransnational Access programme. Applications for sup-port can be submitted via the NUDAME website whichcan be found on the main web portal of IRMM [14].Any type of experiment in the areas of radioactivewaste management, radiation protection and other ac-tivities in the field of nuclear technologies and safetycan be proposed provided our experimental infrastruc-ture can offer a significant added value to the project.Access to the IRMM accelerator installations impliesthe same scientific, logistical and technical support pro-vided to all researchers of the Institute.

Short overview of in-house research areasFor the safety assessment of presently operating reactorsreliable predictions must be made about their behaviourunder different operating conditions. For these calcula-tions the accurate knowledge of changes in neutronspectra are highly important. As an example, the neu-tron multiplicity averaged over the whole mass distribu-tion is of crucial importance for the physics of conven-tional reactors and needs to be known with accuracy bet-ter than 1%. Researchers at IRMM are presently concen-trating on neutron multiplicities, fission neutron spectraand delayed neutrons, total-absorption and neutron cap-ture cross-sections, fission fragment yields and kineticenergy distributions. In view of the assessment of thetemperature dependence of the reactor criticalityDoppler broadening measurements have been carriedout on 238U, 237Np and natHf at different temperatures.Improved capture cross sections for various stable fis-sion products are motivated by the objective to extendand optimize the fuel cycle associated with present nu-clear power plants. These data are also important forcriticality safety of spent fuel storage and transportationof spent fuel in licensed shipping casks. To improvethese data, the IRMM started a collaboration with CEASaclay (F) and ORNL (US) and initiated measurementsat GELINA for 103Rh and 55Mn. The Generation IV International Forum (GIF) pursuesthe in-depth investigation of six advanced concepts fornuclear energy systems, with the objective to arrive atenergy production with a largely reduced volume ofhigh-level radioactive waste, proliferation resistant fuelcycles and much enhanced safety. Future hydrogen pro-duction is envisaged as well. The nuclear data require-ments for the development of these systems address thesame neutron-induced reactions as those for thermal sys-tems, but extending into the 10-20 MeV range. At theGELINA TOF facility high-resolution cross section mea-surements will be carried out for the relevant isotopes

Figure 9. Scheme of flight path area


25


and reaction types. A key issue for the future of nuclearenergy production is a satisfactory solution that must beelaborated for the disposal of nuclear waste. The re-search in this field concentrates on the chemical separa-tion, called partitioning, of long-lived radioactive iso-topes in the nuclear waste and subsequent transmuta-tion into short-lived or stable isotopes. By exposing thematerials to high neutron fluxes transmutation occursvia neutron capture or fission reactions. The goal is toburn the so-called long-lived fission products (LLFP)such as 99 Tc, 129I, and 135Cs, and minor actinides (MA)such as Np, Am, and Cm isotopes. In all cases theknowledge of the associated set of nuclear data is notcomplete. In order to improve the nuclear data high-res-olution total and capture cross section measurementswere performed at GELINA for the long-lived fissionproducts 99Tc and 129I and for the minor actinide 237Np.Measuring 241Am is under preparation. Different types of accelerator driven systems (ADS) fortransmutation of nuclear waste have been proposed. Themost promising one is based on a liquid Pb-Bi spallationtarget. Although the initial neutron energies resultingfrom spallation are in general above the energy range ofGELINA, the neutron spectrum outside the target areaand at larger distances approaches that of a conventionalfast (or thermal) reactor. Using the TOF technique neu-tron capture cross-section measurements have been mea-sured in the resonance region for 232Th, 206,207,208Pb, 209Biand 235,238U. For Pb and Bi isotopes capture measure-ments must be combined with future total cross-sectionmeasurements in the resolved resonance region in orderto lead to the unambiguous determination of the essen-tial parameters. Elastic and inelastic scattering cross-sec-tion measurements have been carried out at GELINA for23Na, 27Al, 56Fe and 238U via (n,n’γ) experiments. The ma-jority of basic and applied measurements in neutronphysics are performed relative to cross-section stan-dards. It is therefore essential that these standards arecontinuously improved and their underlying physicalmechanisms are understood.Under the steering of the OECD and the Data Centre ofthe International Atomic Energy Agency (IAEA) needsfor new standards are identified and proposals are madefor improvements of established standards. The detailedrequirements for neutron data measurements, and inparticular for improvements of the standards database,are collected in the high priority list of the NEA. For ex-ample, the 10B(n,α) 7Li reaction cross section, recently in-vestigated at GELINA, is amongst the most importantstandards used in neutron measurements.The techniques developed for high-resolution neutroncross section measurements in the resonance region gen-erate also spin-off techniques, not directly belonging toour core-business. A new fully non-destructive method

‘Neutron Resonance Capture Analysis’ (NRCA) has beendeveloped, in collaboration with the Delft University ofTechnology. NRCA allows the determination of the ele-mental composition of samples.The method is based on the use of neutron resonances asfingerprints to identify and quantify elements. Details ofthe NRCA technique are discussed in another contribu-tion to this issue [15].

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needs,” J. Nucl. Sci. and Techn., Suppl. 2, 4, (2002).

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3. S.M. Qaim, “Nuclear data for production of new medical

radionuclides,” J. Nucl. Sci. and Techn., Suppl. 2, 1272, (2002).

4. T. Biro, “Neutrons as tools in safeguards and combating illicit

trafficking of nuclear material,” Proceedings of the workshop The

Nuclear Measurements and Evaluations for Applications (NEMEA-

2), Budapest, Hungary (November 5-8, 2003).

5. M. Moxon, “REFIT2: A least Squares Fitting Program for Resonance

Analysis of Neutron Transmission and capture Data,” NEA-0914/02

(1989).

6. C. Coceva, M. Frisoni, M. Magnani, A. Mengoni, “On the figure of

merit in neutron time-of-flight measurements,” Nucl. Inst. and Meth.

A, 489, 346-356, (2002).

7. A. Bensussan, J.M. Salome, “Gelina: a modern accelerator for high

resolution neutron time of flight experiments,” Nucl. Inst. and Meth.,

155, 11-23, (1978)

8. D. Tronc, J.M. Salome, K. Böckhoff, “A new pulse compression

system for intense relativistic electron beams,” Nucl. Inst. and Meth.,

228, 217-227, (1985).

9. M. Flaska, A. Borella, D. Lathouwers, L.C. Mihailescu, W.

Mondelaers, A.J.M. Plompen, H. van Dam, T.H.J.J. van der Hagen,

“Modeling of the GELINA neutron target using coupled

electronphoton-neutron transport with the MCNP4C3 code,” Nucl.

Inst. And Meth. A, 531, 392-406, (2004).

10. J.M. Salome, R. Cools, “Neutron producing target at GELINA,” Nucl.

Inst. and Meth., 179, 13-19, (1981).

11. M. Flaska, D. Lathouwers, A.J.M. Plompen, W. Mondelaers, T.H.J.J.

van der Hagen, H. van Dam, “Potential for improvement of a

neutron producing target for time-of-flight measurements,” Nucl.

Inst. And Meth. A, 555, 329-339, (2005).

12. A. Borella, “Determination of the neutron resonance parameters for

206Pb and of the thermal neutron capture cross section for 206Pb and

209Bi,” Ph.D. thesis, Ghent University, Belgium (2005).

13. L.C. Mihailescu, L. Olah, C. Borcea, A.J.M. Plompen, “A new HPGe

setup at GELINA for measurement of gamma-ray production cross

sections from inelastic neutron scattering,” Nucl. Inst. and Meth. A,

531, 375-391, (2004). http://www.irmm.jrc.be/html/homepage.htm

14. H. Postma and P. Schillebeeckx, “Neutron-resonance capture as a tool

to analyse the internal compositions of objects non-destructively”, in

this issue

26


Early history of the instituteThe reactor embedded in the ReactorInstitute Delft first came to Europeas a part of the “Atoms for Peace”exhibit in the late 1950s.Near Schiphol airport, all those vis-iting the exhibit were allowed toclimb a ladder, peer straight into thecore and see the Cerenkov radia-tion. When the exhibit was discon-tinued, it was decided to keep thereactor in the Netherlands andfound the Reactor Institute Delft, tobe operated by the University ofDelft. The reactor was upgraded

from 100 kW to 2 MW over theyears. The name of the institutechanged a number of times, from itsoriginal name to “InteruniversitaryReactor Institute” to “InterfacultyReactor Institute”, and back to “Re-actor Institute Delft” (RID).The first name changes correspond-ed to changes in ownership, the lastone also denotes the regrouping ofthe scientific departments into a sin-gle department af the Applied Sci-ences Faculty named “Radiation, Ra-dionuclides and Reactors” (R3), andthe reactor and instrument opera-

tions in the RID branch of the sameApplied Sciences faculty.

Recent history and NMI3 transnationalaccessIn the 1990s, the original reactor con-tainment building was extendedwith a beam-guide hall offeringmore neutron beams and more floorspace to the instruments. Only a fewyears later, the main building was al-most doubled in size, both with re-spect to laboratories and to officespace. Last year, the RID already

M & N & SR NEWS

Reactor Institute Delft and the R3 departmentThe academic Dutch neutron facilityM. BlaauwReactor Institute Delft Mekelweg 15 2629 JB Delft The Netherlands

On February 17, 2006, the website:www.lightsources.org/celebrated itsfirst year on line.An international group of sciencecommunicators developed and man-ages lightsources.org for the com-munity of synchrotron and free elec-tron laser (FEL) light sources withthe aim of serving its users, as wellas the general public, by acting as afocal point for news, informationand educational resources.In particular, users can find• information about and links to

all major light sources• a calendar of meetings, work-

shops, conferences and proposaldeadlines

• announcements of job opportu-nities

• links to useful resources.Besides a comprehensive imagebank, features of interest for both

the specialist and the general publicinclude an archive of press releases(more than 150) and synchrotron/FEL-related news items culled dailyfrom publications and news services(over 600) which provide, in an en-joyable form, insights into the manyapplications of synchrotron radiation.The site offers the option of easilysubscribing to a News Flash servicewhich distributes via e-mail eitherdaily notices as soon as interestingnews is released to the public or aweekly digest of news. An RSS feedis also available.Suggestions aimed at making thesite even more appealing for its pub-lic are highly welcomed and can besubmitted through the webmaster atthe address:[email protected] success of the site is document-ed by its continually increasing web

traffic, which is now averaging over160’000 page views per month.lightsources.org Management Board

M. Bertolo

Lightsources.org enters its second year of operation

Courtesy:lightsources.org


27

M & N & SR NEWS

having been a member of the NMI3(Integrated Infrastructure Initiativefor Neutron Scattering and Spec-troscopy) consortium for a while,it was decided within NMI3 to pro-vide 120 days of beam time access tousers from European and associatedstates through the transnational ac-cess mechanism. Only months afterthis decision becoming final, usersare submitting proposals at a rateforcing us to implement peer reviewmechanisms. Our first official, en-forced deadline for proposals will beJanuary 1, 2007 as a result.

Unique and rare experimentalopportunitiesThe RID offers the only neutronbeam facilities in a radius of 500 km,and that in an academic setting. To-gether with the R3 department, along-standing reputation for instru-ment innovation is being worked oncontinuously. We have several

unique experimental opportunitiesto offer as a result. To name a few:The innovative SESANS instrumentthat can see structures of up to 20mm in real space. The very intensepositron beam POSH (4x108 s-1), con-nected to a beautiful 2D-ACAR set-up. The facilities for InstrumentalActivation Analysis of samples up to15 litres. More information on ourfacilities can be found on our web-site: www.rid.tudelft.nl.

The Radiation, Radionuclides &Reactors departmentRadiation is what binds the Radia-tion, Radionuclides & Reactors depart-ment together. However varied ourareas of interest, whether they bematerials, sensors and instrumenta-tion, energy and sustainable produc-tion or health, all our research issomehow related to radiation. To-day, the focus of the R3 research is onenergy and health. The close collabo-

ration with the RID not only guaran-tees access to the reactor and the ir-radiation facilities, but also results inthree centres of knowledge: thePositron Centre, the Neutron Centreand the Netherlands Centre for Lu-minescence Dating (NCL). The con-fluence of all this knowledge makesour research unique in the Nether-lands, perhaps even in Europe.The R3 department consists of fivesections:Physics of Nuclear Reactors (PNR) de-signs and analyses new nuclear reac-tor systems to improve the sustain-ability of nuclear power.Fundamental Aspects of Materials andEnergy (FAME) investigates func-tional and structural materials witha view to practical applications. Themain focus is on the relationship be-tween structure, dynamics and func-tion on atomic and nanoscales. So-lar-cell materials, hydrogen storage,batteries and related subjects are thecurrent focus.

28


M & N & SR NEWS

Neutron and Positron Methods in Ma-terials (NPM2) develops instrumentsand methods for the optimal use ofneutrons and positrons, ultimatelyfor use within the large, internation-al facilities – but to a first-generationuser, one needs to come to Delft!Radiation and Isotopes for Health (RIH)innovates and optimises the use ofradiation and radioisotopes in thehealth sciences. The research focuseson innovative production pathwaysand applications of radioisotopes,but also on radioactive compounds,radiation burden and image qualityin diagnostics and therapy.Radiation Detection & Matter

(RD&M) performs fundamental andapplied research on radiationsources, radiation detection princi-ples, in particular luminescence andscintillation phenomena, and appli-cations in medical diagnostics, thera-py and dosimetry, humanitariandemining and security, neutron de-tection, geology, art and archaeology.

The futureJust a few weeks ago, the director ofR3 and RID, Tim van der Hagen,stated that the prospects and futureoutlook for the Delft neutrons hadnever been better than right now. We

have detailed plans for installationof a cold neutron source at the Delftreactor, including instrument im-provements that will be possible asresult, as well as entirely new instru-ments currently only dreamed of.The RID has a clearly defined oblig-ation to maintain and improve theexisting instruments, as well as tofind and assist users from the out-side world. Once, not so long ago,we kept our wonderful instrumentsand possibilities mostly to ourself.Now, we are opening up and al-ready the benefits of this attitude arebecoming apparent.

The deadline for proposal submis-sion to the ILL is Tuesday, 19 Septem-ber 2006, midnight (European time).Proposal submission is only possi-ble electronically. Electronic Pro-posal Submission (EPS) is possiblevia our Visitors’ Club (www.ill.fr,Users & Science, Visitors’ Club, ordirectly at http://vitraill.ill.fr/cv/),once you have logged in with yourpersonal username and password.The detailed guide-lines for the sub-mission of a proposal at the ILL canbe found on the ILL web site:www.ill.fr, Users & Science, User In-formation, Proposal Submission,Standard Submission. The web system will be operationalfrom 1 July 2006 , and it will beclosed on 19 September, at midnight(European time).You will get full support in case ofcomputing hitches. If you have anydifficulties at all, please contact ourweb-support ([email protected] ).

Instruments availableThe following instruments will beavailable for the forthcoming round:

• powder diffractometers: D1A,D1B*, D2B, D20, SALSA

• liquids diffractometer: D4• polarised neutron

diffractometers: D3, D23*• single-crystal diffractometers: D9,

D10, D15*, VIVALDI • large scale structure

diffractometers: D19, DB21, LADI• small-angle scattering: D11, D22• reflectometers: ADAM*, D17 • small momentum-transfer

diffractometer: D16• diffuse-scattering spectrometer:

D7• three-axis spectrometers: IN1,

IN3, IN8, IN12*, IN14, IN20,IN22*

• time-of-flight spectrometers: IN4,IN5, IN6

• backscattering and spin-echospectrometers: IN10, IN11, IN13*,IN15, IN16

• nuclear-physics instruments:PN1, PN3

• fundamental-physicsinstruments: PF1B, PF2

* Instruments marked with an aster-isk are CRG instruments, where a

smaller amount of beam time isavailable than on ILL-funded instru-ments, but we encourage such appli-cations. You will find details of theinstruments on the web:www.ill.fr/index_sc.html

Scheduling periodThose proposals accepted at the nextround, will be scheduled during thefirst two cycles in 2007.

New From ILLILL Next standard proposal round

Provisional Reactor Cycles for 2007*

Cycle n° 146 (071) From 30/01/2007

To 21/03/2007

Cycle n° 147 (072) From 04/04/2007

To 24/05/2007

Cycle n° 148 (073) From 21/08/2007

To 10/10/2007

Cycle n° 149 (074) From 25/10/2007

To 20/12/2007

Table 1. The ILL reactor cycles in 2007. Start-upsand shut downs are planned at 8:30 am


29

M & N & SR NEWS

College Secretaries

College 1- Applied physics,instrumentation &techniques: Emanuel Farhi

College 2- Theory: Olivier Cepas

College 3- Nuclear and FundamentalPhysics: Torsten Soldner

College 4- Structural and MagneticExcitations: Martin Boehm

College 5A- Crystallography: PaulHenry

College 5B- Magnetism: NolwennKernavanois

College 6- Structure and Dynamics ofLiquids and Glasses:Claudia Mondelli

College 7- Spectroscopy in solid statephysics and chemistry:Peter Fouquet

College 8- Biology: Ingrid Parrot

College 9- Structure and Dynamics ofSoft-condensed Matter:Ralph Schweins

New keywords system for the colleges!With the instrument SALSA fully op-erational, and the forthcoming com-missioning of the Tomography sta-tion and SALSA (without forgettingFaME 38), an increase of proposalsdealing with more applied engineer-ing research is expected.This raises the problem of properlyjudging these proposals: whilst somepeople would be interested in ap-plied topics others would be inter-ested in pure science only.For this reason, we decided to in-clude a new College – and corre-spondent subcommittee panel – inthe proposal evaluation system:

College 1: Applied physics,instrumentation & techniques• 1-01 Metallurgy, strain/texture

measurement and metal physics• 1-02 Tomography• 1-03 Applied sciences• 1-10 Instrumentation for neutron

scattering• 1-20 Techniques for neutron

scattering

An additional re-organisation of theColleges 4 and 7 in terms of coher-ence, mainly aims at achieving amore straightforward attribution ofproposals to both colleges. Magneticand non magnetic excitations will bedealt in the future by college 4 andcollege 7, respectively.A detailed keywords list is availableon the ILL web (www.ill.fr) underwww.ill.fr/pages/science/User/UKeywds.html

The GAMS gamma-ray spectrome-ters at the Institut Laue-Langevin(ILL) have always been unique in-stallations combining one of theworld most intense continuous ther-mal neutron sources with the extra-ordinary resolving power of the two-axis crystal spectrometers. This combination delivers extraordi-nary results to various fields ofphysics. The majority of these contri-butions are related to the ongoingimprovement in resolving power ofthe instruments.This parameter has now approachedits theoretical limit and therefore it is

the moment to discuss what futurephysics should be investigated onthe GAMS spectrometers. During the last few years a variety ofnew proposals for exciting applica-tions at GAMS in very differentfields have been made. Therefore,during the two days of the work-

shop we would like to bring togeth-er new and old GAMS users to helpdefining the future physics and tech-nical developments of these spec-trometers.

G. Cicognani

New From ILLAP.G.RA.D(E), Application of γγ-ray diffraction (October-November 2006)

Further information on the workshop can be obtained from the website

www.ill.fr/apgrade/First-Announce.htm

* Please note that these dates

might change.

We therefore encourage you

to consult the ILL website,

where possible changes will

be indicated.

30


M & N & SR NEWS

The Department of Energy’s ThomasJefferson National Accelerator Facili-ty (DOE’s Jefferson Lab) in NewportNews, Va., is home to the Continu-ous Electron Beam Accelerator Facil-ity (CEBAF), an accelerator capableof providing a 5.75 GeV electronbeam for research to any of its threeexperimental halls.CEBAF uses a state-of-the-art photo-cathode gun system that is capableof delivering beams of high polar-ization and high current to twohalls, while maintaining high-polar-ization, low-current beam to thethird. A chopping system operatingat 499 MHz is used to develop a 3-beam 1497 MHz bunch train at 100keV. The beam is then longitudinally

compressed in the bunching sectionto provide 2 picosecond bunches,which are then accelerated to justover 1% of the total machine energyin the remaining injector section. The beam from the injector is accel-erated through a unique recirculat-ing beamline that looks much like aracetrack, with two linear accelera-tors (linacs) joined by two 180° arcswith a radius of 80 meters. The total track measures about akilometer in length. Twenty cry-omodules, each containing eight su-perconducting niobium cavities,make up the two linacs. Liquid heli-um keeps the accelerating cavitiessuperconducting at a temperature of2 Kelvin. Quadrupole and dipole

magnets in the tunnel steer and fo-cus the beam as it passes througheach arc. More than 2,200 magnetsare necessary to keep the beam on aprecise path and tightly focused.Beam is directed into an experimen-tal hall’s transport channel usingmagnetic or radiofrequency (RF) ex-traction. The RF extraction schemeuses 499 MHz cavities, which kickevery third bunch out of the ma-chine. The accelerator can deliverthe first four passes to one hall only;the fifth pass can be sent to all threehalls simultaneously. The beam issent into targets in any or all of thethree experimental halls: Hall A,Hall B and Hall C. Hall A’s standardequipment includes a pair of High

Jefferson Lab’s CEBAF Continues Experiments WhileGearing Up for an Increase in Energy

Hall A. The GEn experiment, which measured the electric form factor of the neutron in Jefferson Lab’s Hall A, concluded data taking in May 2006.


31

M & N & SR NEWS

Resolution Spectrometers (HRS), de-signed for electron and hadron de-tection. Hall B’s CEBAF Large Ac-ceptance Spectrometer (CLAS) en-capsulates the target, providing vir-tually 4π acceptance. Hall C is highly versatile, allowingfor large equipment installations,with two pieces of standard equip-ment, the High Momentum Spec-trometer and the Short Orbit Spec-trometer.Jefferson Lab is a DOE Office of Sci-ence, Office of Nuclear Physics re-search facility. It was envisioned andrequested by physicists as a neces-sary tool to answer emerging ques-tions about the quark structure ofmatter in 1976, and construction ofthe facility began in 1987. CEBAFprovided beam for its first set of ex-periments in 1994. Research carried out at the Lab ad-dresses questions in three main areas

in nuclear physics: the structure ofnucleons, the structure of the nucle-us, and symmetry tests in nuclearphysics. For example, the GE

n exper-iment in Hall A measured the elec-tric form factor of the neutron athigh Q2. Recent results on the elec-tric form factor of the proton, GE

p,

showed that the ratio GEp/GM

p de-creases sharply as Q2 increases.The same mechanisms that causesuch a deviation should also be pre-sent in the neutron, but until this ex-periment, no accurate data existed atthese momentum transfers. Hence,this test is essential for understand-ing the structure of the nucleon andfor providing key information forthe analysis of processes involvingelectromagnetic interactions withcomplex nuclei. CEBAF will contin-ue its research program far into thefuture with the planned 12 GeV Up-grade. DOE recently awarded Jeffer-

son Lab Critical Decision One (CD-1)approval for the Upgrade, whichmoves the project from the Concep-tual Design phase to the Project En-gineering and Design phase. The 12 GeV Upgrade Project willdouble CEBAF’s electron beam ener-gy from 6 GeV to 12 GeV and willupgrade the scientific capability offour experimental halls (adding onenew hall, Hall D).The first Program Advisory Com-mittee to review 12 GeV proposalswill take place in August 2006; de-tails may be found at:http://www.jlab.org/exp_prog/PACpage/PAC30/.

A.E. EkkebusSpallation Neutron Source

ORNL

Upgrade. The 12 GeV Upgrade of CEBAF will double the machine’s electron beam energy and provide increased scientific capability in fourexperimental halls.

32


M & N & SR NEWS

Spallation Neutron Source Progress February 2006

SummaryThe SNS Project is 96.3% completethrough December 2005 Strongsafety performance continues as theproject has worked in excess of 7.4million hours, with only 2 lost workday (away) cases through Decem-ber 2005.

InstrumentsThe first procurement contract forsample environment equipment hasbeen awarded.Magnetism Reflec-tometer components [instrument,omega, and detector stages] weremoved into its cave. Hutch installa-tion is complete. Over 30 motor controls have beeninstalled for instrument operation.Phase 1 installation of the Funda-mental Neutron Physics Beamline(BL-13) was completed in earlyFebruary.The first production detector for thePOWGEN and Vulcan instrumentswas tested at the SNS test beam lineat HFIR. The initial measured per-formance exceeded expectations.Gluing of silicon crystals to back-plates has been completed for totalof six backscattering crystal assem-blies for the backscattering spec-trometer.Bids for construction of the CNCSSatellite building are due later thismonth. The first two sections of the ARCSneutron guide were successfully in-spected at the manufacturer, withshipment beginning later thismonth.Five choppers have been installedon the first three instruments.

TargetSignificant activity is underway toprepare for the Target portion of theAccelerator Readiness Review thatwill be held in April.All core vessel inserts, shutters, andshutter drives have been installedthat were scheduled to be completedbefore CD-4. Full Operational Inte-grated System Tests of the target sys-tems continue.The shine shield blocks above theTarget were installed and testingwas completed for the primary andsecondary containment exhaust.Completed shutter testing for thethree shutters required to be opera-tional for CD-4.Completed demonstration tests fortarget module replacement using on-ly the remote handling equipment.All of the remote handling tests andprocedures have been completed.

AcceleratorThe SNS ring commissioning run inits 24/7 mode was concluded asplanned on February 3. Installationof the remaining Ring-to-Targetcomponents is underway.

Project and Site SupportThe build-out of the CLO auditori-um has begun with completionscheduled for May.

Future meetings and deadlines ofinterest to SNS usersSNS Instrument Development Teammeetings:NOMAD (disordered materials dif-

fractometer), March 13, 2006, Balti-more (at APS)HYSPEC (hybrid spectrometer),April 7, 2006, BrookhavenSNAP (high-pressure diffractome-ter), April 10-11, 2006 Oak RidgeTOPAZ (single crystal diffractome-ter), May 8-9, 2006, Oak RidgeWorkshop on Polarized InelasticNeutron Scattering (PINS), April 6-7,2006, Brookhaven.http://www.bnl.gov/pins/ Imaging and Neutrons, summer2006, Oak Ridge, in preparation[http://www.sns.gov]International Symposium on Poly-mer Analysis and Characterization(ISPAC), June 12 - 14, 2006, OakRidge.http://www.chem.cmu.edu/ispac/ American Conference on NeutronScattering, June 18-22, 2006, St.Charles, IL, http://acns2006.anl.gov. Session on Noninvasive ScatteringTechniques for Nanoaerosol Charac-terization: Neutrons, X-rays andLight, within the 25th annual meet-ing of the American Association forAerosol Science and the 7th Interna-tional Aerosol Conference, Septem-ber 10-15, 2006, St. Paul, Minnesota.http://www.aaar.org/IAC2006/in-dex.htm.Short course: Neutron ScatteringApplied to Earth Sciences, Miner-alogical Society of America, Decem-ber 7-8, 2006, Emeryville, CA. http://www.minsocam.org/msa/sc/neutron_descrptn.html.

A.E. EkkebusSpallation Neutron Source

ORNL


33

M & N & SR NEWSM & N & SR NEWS

At the Forschungszentrum Ros-sendorf in Dresden, Germany, thesuperconducting electron acceleratorELBE (Electron Linear acceleratorwith high Brilliance and low Emit-tance) has come into operation in2002 (for a layout of the building seeFig. 1).It provides electrons with energiesup to 40 MeV and an average beam

current of 1 mA, which are used togenerate radiation and particlebeams of several kinds: MeVbremsstrahlung for nuclear(astro)physics experiments, mono-chromatic hard-X-ray channeling ra-diation for radiobiological experi-ments, and in the near future alsoneutrons and positrons (for details,see www.fz-rossendorf.de/elbe).

Yet one of the main tasks of the elec-tron beam is to drive two infrared(IR) free-electron lasers (FEL),which will be briefly described inthis article. In May 2004, first lasing has beendemonstrated [1] and by now theavailable wavelength range is 4 to22 µm for electron energies between15 an 32 MeV [2].

The presently operating FEL is basedon a 27-mm-period, hybrid perma-nent-magnet undulator (U27) with2x34 periods, of the same type asemployed at the Tesla Test Facility(TTF) at DESY, Hamburg.Starting in 2005, the FEL has beenoperated as a user facility – underthe name FELBE (www.fz-rossendorf.de/felbe) – with a peer-

reviewed proposal system, beingopen to users worldwide.In particular, users from EC and as-sociated countries can be supportedunder the “Transnational Access”program within the EC funded ”In-tegrating Activity on Synchrotronand Free Electron Laser Science (IA-SFS)”. This latter project is an “Inte-grated Infrastructure Initiative” (I3)

which comprises most synchrotronand FEL facilities in Europe and iscoordinated by ELETTRA in Trieste.In order to extend the availablewavelength range, a second undula-tor (hybrid permanent magnet with100 mm period and 38 periods) ispresently being set up.This second FEL is predicted to cov-er the far-infrared/THz range from

FELBE: a new infrared free-electron-laser user facilityM. Helm and P. MichelForschungszentrum Rossendorf, P.O. Box 510119, 01314 Dresden, Germany

Figure 1. Layout of the ELBE building.

34


Figure 3. Pump-probe signal of a semiconductor superlattice at two different wavelengths. For details, see Ref. 3.

M & N & SR NEWS

Figure 2. Autocorrelation trace and corresponding spectrum of an FEL pulse at 11 µm. The inset gives the fitted width of the autocorrelation trace as wellas the deduced effective pulse width.

approximately 15 to 150 µm (the lat-ter corresponding to 2 THz). In thiswavelength range still no other high-power, narrow-band sources existapart from FELs. The key feature which distinguishesFELBE from other FEL user facilitiesis the possibility of quasi cw opera-tion (meaning a continuous mi-cropulse train), made possible by thesuperconducting accelerator cavities.These niobium RF cavities were alsodesigned for the Tesla Test Facilityand are kept at 2 K using superfluidHe. The FEL thus provides picosec-ond optical pulses at a repetitionrate of 13 MHz.In this mode, the average power canreach up to 10 W, corresponding tonearly 1 µJ pulse energy. For reducedaverage power, macrobunching ispossible as well, yielding >100 µslong macropulses at a <25 Hz repeti-tion rate. By comparing autocorrelation traceswith optical spectra the pulses havebeen proven to be bandwidth limit-ed. At a fixed wavelength the pulselength (and thus the spectral width)can be varied by a factor of 5 by ad-justing the cavity detuning and thusthe gain.An example is shown is Fig. 2,where autocorrelation and spectrumare plotted for the shortest pulses(0.9 ps) obtained so far at this wave-length of 11 µm (at shorter wave-lengths also shorter pulses are ex-pected).Experiments are performed in the IRuser labs, as shown in the upper leftcorner of the sketch in Fig. 1.The optical tables and the (remotelycontrolled) beam distribution systemare indicated.A lot of ancillary equipment is pro-vided, most importantly a numberof table-top optical sources (in vari-ous wavelength ranges) based onfemtosecond Ti:Sapphire lasers,

which are synchronized with theFEL to better than a picosecond. One of the user labs is commissionedfor handling of radioactive sub-stances, thus allowing for IR spec-troscopy on radioactive samples.Experiments which have been per-formed so far include: • Imaging/mapping of thin molec-

ular films on surfaces by polariza-tion-modulation IR reflection-ab-sorption spectroscopy.

• Scattering scanning-near-field op-tical microscopy (SNOM) on fer-roelectric-crystal surfaces.

• Pump-probe spectroscopy onsemiconductor quantum struc-tures.

What has been seen in all types ofexperiments so far is the unprece-dented signal-to-noise ratio madepossible by working in cw mode.As an example we present in Fig. 3 apump-probe signal of a semiconduc-tor superlattice, which shows thebleaching of the interminiband ab-sorption and subsequent electronthermalization and cooling [3]. In the near future the IR beam of the

FELs will be guided into the recentlyopened, nearby high-magnetic-fieldlaboratory Dresden (HLD; www.fz-

rossendorf.de/HLD), which willprovide magnetic-field pulses in the60-100 Tesla range with 1000-10 mspulse duration, thus opening theway for many new spectroscopic in-vestigations, in particular in solidstate physics. The work which has been brieflysummarized here has of course beena large undertaking of many people,whose dedicated efforts over manyyears are gratefully acknowledged.

References1. P. Michel et al., in Proceedings of the 26th

International FEL Conference, Trieste, 2004

(http://accelconf.web.cern.ch/AccelConf/f

04/papers/MOAIS04/MOAIS04.pdf)

2. U. Lehnert, P. Michel, W. Seidel, D. Stehr, J.

Teichert, D. Wohlfarth, and R. Wünsch,

Proceedings of the 27th International FEL

Conference, Stanford, 2005.å

(http://accelconf.web.cern.ch/AccelConf/f

05/papers/TUPP030.pdf)

3. D. Stehr, S. Winnerl, M. Helm, T. Dekorsy, T.

Roch, and G. Strasser, Appl. Phys. Lett. 88,

151108 (2006).

FOR INFORMATION ON:

Conference Announcements and Advertising for Europeand US, rates and inserts can be found at:

www.cnr.it/neutronielucedisincrotrone

Pina CasellaTel. +39 06 72594560e-mail: [email protected]


35

M & N & SR NEWS

36


NEWS AND MEETING REPORTS

The 1st International Workshop onthe Dynamics of Molecules and Ma-terials will be held in Grenoble at theILL/ESRF site from Wednesday 31January to Friday 2 February 2007.The Workshop will bring together

scientists studying complex materi-als and molecular systems that aretypically only available in polycrys-talline form. Insight into the intrinsicdynamical properties of these mate-rials can be obtained either by an in-

tegrated dynamic response as aphonon density of states or throughselected individual phonons.The principal aim of the Workshopis an exchange of results and ideasfrom different techniques and meth-

1st International Workshop on the Dynamics of Moleculesand Materials (31 January to 2 February 2007, Grenoble)

Five years ago the ILL convened thefirst Millennium Symposium tolaunch an ambitious modernisationprogramme of instruments and in-frastructure called the ILL Millenni-um Programme. Five years of hardwork by the ILL staff in all divisions,with enthusiastic support from ourusers, have further expanded theILL’s suite of unique world’s-best in-struments and yielded many-foldgains in efficiency and quality onseveral existing instruments. TheSecond Symposium with our userswas held at the end of April todemonstrate the achievements of theMillennium Programme to date, andto boost the ILL’s ambitious plansfor the coming decade.The scientific programme included acombination of presentations of sci-entific results and frontier achieve-ments in methods and neutron tech-niques, mostly by our users.ILL scientists and engineerw alsopresented their ambitious plans forinstrument developments andanalysis techniques in the comingdecade. Seven parallel sessions al-lowed intense discussion and feed-

back from the users in smallergroups. No holds were barred, yetall criticism will be considered indepth. The hectic schedule of 21 ple-nary talks, 49 talks in parallel ses-sions, 3 summary talks, and 73posters, many on instrument devel-opments at other neutron facilities,ensured lively discussion at the cof-fee breaks. The poster A document“Perspectives and Opportunities forILL”, which will include projects forinstruments, infrastructure and userinterface facilities as well as renewalplans of key components of the reac-tor, moderators and neutron guides,is in preparation. Feedback from the users, expressedduring the Symposium, or on theSymposium web site, will guidethese objectives.The Second Millennium Sympo-sium was also an opportunity to re-new old acquaintances. Prof DirkDubbers, the father of the Millenni-um Programme, was the honorarychairman. We were also honouredby the sprightly presence of twoother former ILL Directors, BernardJacrot and Peter Schofield, as well

as the future British Director, An-drew Harrison. Waning but notgone yet Colin Carlile enthralled usall with a stellar after-dinnerspeech, but finally did not pass onhis coveted joke book. Perhaps itwill resurface in Swedish? Victimof the only technical hiccough ofthe Symposium, a talk with fewerfigures than he expected, WernerKuhs was justly rewarded for hisperseverance by the gift of a raresigned local publication.The extended family of the Diffrac-tion Group may however choose aless conspicuous table at the ThirdMillennium Symposium.Often hidden behind the scenes, Bar-bara Standke and Claire Gubianwelcomed all attendees, Sylvie Per-roux weaved the web site, Paul Hen-ry and Peter Fouquet wielded Allenkeys, the staff of SI provided excel-lent on-site computer facilities, Fran-coise Vauquois gave a hand in thecommunication of the event andSerge Claisse caught the magic mo-ments seen here.

The ILL Millennium Symposium and European UserMeeting (27-29 March)


37


ods, both experimental and compu-tational. We want to receive inputfrom the user community in order toidentify future trends, the most in-formative experiments to be done, aswell as needs for modelling and new

instrumentation. The Workshop is organized jointlyby the ILL and the ISIS Facility andit will be held at the premises of theEuropean Synchrotron Radiation Fa-cility at the common ILL-ESRF site

in Grenoble. Further information can be obtainedfrom the websitehttp://www.ill.fr/Events/DMM/

ILL SOFT MATTER USER MEETING First announcement INSTITUT LAUE-LANGEVIN Grenoble, France(22-24 November 2006)This is the first announcement for anILL Soft Matter User Meeting orga-nized by the Institut Laue-Langevin.The workshop should gather scien-tists whose interest is to apply elasticand inelastic neutron scattering totheir own soft matter research.It will offer an opportunity to pre-sent and to discuss recent neutronscattering research in this field andto identify the needs of the soft mat-ter ILL-user community.In particular, it is proposed to ad-dress the questions of on-site char-acterization and preparation ofsamples, complementary methodsand optimization of the use ofbeam-time.In view of the possible creation of aPartnership for Soft Condensed Mat-ter on the ILL-ESRF site this work-shop will give the unique opportuni-ty to raise user interests concerningstructure, scientific orientation andequipment in an early stage. Neu-tron scattering techniques are pow-erful tools for the characterization ofthe structure and dynamics of soft-matter systems. The advantage ofneutrons in soft-matter studies de-rives mainly from the fact that neu-trons are strongly scattered by lightatoms and the scattering power can

vary for different isotopes of thesame atom. This allows the use ofcontrast variation for highlightingthe interesting parts of the systemswith a fraction of nanometer resolu-tion. Concerning dynamics the ex-traordinarily high incoherent scatter-ing cross section of hydrogen per-mits the exploration of the time de-pendent self correlation of soft mat-ter. Other advantages include thepossibility of studying buried sys-tems, to apply external stimuli innon-equilibium experiments such asRheo-SANS , do in-situ measure-ments, and the fact that neutronbeams are non-destructive.Because of their fragile nature, soft-matter samples are often preparedon site just before a neutron experi-ment and in many cases their qualityneeds to be pre-assessed for an effi-cient use of neutron beam-time.Soft matter scientists are invited toparticipate in this workshop and topresent their work in the fields ofpolymers, colloids and interface sci-ence, involving both neutrons andcomplementary techniques. Ampletime will be reserved for discus-sions in order to define the needs ofthe community concerning an on-site facility for sample preparation/

deuteration and pre- as well as post-characterization.Abstracts can be submitted for bothoral and poster presentations at theworkshop web-site: http://www.ill.fr/SOFTILL2006<http://www.ill.fr/softill2006>.Deadline for abstract submission isJuly 19th 2006. Registration is free.Accommodation in the guest-housewill be offered limited to the avail-able places and on a first come-first

served basis.For any further information you cancontact us at [email protected] <mail-to:[email protected]>

G. Fragneto

Chair: Stefan Egelhaaf

Advisory Committee: Christiane

Alba-Simionesco, Robert

McGreevy, Richard Jones, Dieter

Richter, Peter Schurtenberger

Local Organizing Committee: Trevor

Forsyth, Giovanna Fragneto,

Bernhard Frick, Isabelle Grillo,

Peter Lindner, Peter Timmins,

Christian Vettier

The Very Low Angle Detector(VLAD) bank has been installed re-cently on the VESUVIO spectrome-ter, at the ISIS facility, UK. VLADwas inaugurated on the 12th Decem-ber 2005 by Dr Andrew Taylor, theHead of Facility, with a reception forthe scientists, engineers and techni-

cians involved in the work.VESUVIO–an inverted geometrytime-of-flight neutron spectrometer–was originally designed for mo-mentum distribution investigationsof light nuclei in condensed matter.Where the application of the deepinelastic neutron scattering tech-nique, in the Compton regime, is ex-ploited. (Here, high energy transfers,>1eV, and high momentum trans-fers, >20 Å-1, are required.) Recently, the experimental setup ofVESUVIO underwent a major up-grade within the EU funded project,eVERDI, involving the Universitàdegli Studi di Roma Tor Vergata,Università degli Studi di Milano Bic-occa, University of Kent at Canter-bury and the ISIS Facility.The project included, among otheritems, the installation of the VLAD

bank, covering the angular range of1°<2 <5°. This allows neutron scatter-ing with high energy transfers butnow at low momentum transfers(q < 10 Å-1). It uses a novel neutrondetection technique (n,γ-resonancedetection) which was developedwithin the eVERDI project (VESU-VIO upgrade). Here, gamma detec-tors record the photon cascade fol-lowing the resonant capture of thescattered neutrons by a thin 238U foil.The γ-detector consists of a ceriumdoped yttrium aluminium perovskite(YAP) scintillator coupled to a photo-multiplier tube.With the current setup the accessibil-ity of a yet unexplored dynamicalrange of inelastic neutron spec-troscopy at eV energies has beenachieved, facilitating the investiga-tion of electronic transitions in rareearth metals and compounds, vibra-tional levels in insulators, semicon-ductors, and magnetic materials.

John Tomkinson

ISIS Neutron Source

38



Prof. Giuseppe Gorini (Università degli Studi diMilano Bicocca, Italy) illustrates the principlesof operation of the VLAD bank.

e.VERDI Project VLAD INAUGURATION(12 December 2005)

Andrew Taylor, Carla Andreani and ColinWindsor celebrate the coming of age of the n,γ-resonance detection technique at the VLADinauguration, December 2005 at ISIS .

The inauguration reception of the VLAD bank, hosted by Andrew Taylor, seen here next to Prof.Carla Andreani (Università degli Studi di Roma Tor Vergata, Italy). On the front row, left to right, DrUschi Steigenberger (ISIS), Prof. Giuseppe Gorini (Università degli Studi di Milano Bicocca, Italy),Dr. Andrew Taylor (ISIS), Prof. Carla Andreani (Università degli Studi di Roma Tor Vergata, Italy),Prof. Marco Zoppi (CNR, Italy) and Prof. George Reiter (University of Huston, USA)

39


CALL FOR PROPOSAL

Call for proposals forNeutron Sourceshttp://neutron.neutron-eu.net/n_about/n_where/europe

BENSCDeadlines for proposal submission: 15th September 2006www.hmi.de/benscwww.hmi.de/bensc/user-info/call-bensc_en.html

BNCDeadlines for proposal submission: 15th October 2006www.bnc.huwww.bnchu/modules.php?name=News&file=article&sid=105http://nfdfn.jinr.ru

FRJ-2Deadlines for proposal submission: Anytime during 2006www.fz-juelich.de/iff/wns/

FRM-II Deadlines for proposal submission: Anytime during 2006wwwnew.frm2.tum.de/en.html

GeNFDeadline for proposal submission: Anytime during 2006www.gkss.de/index_e_js.hmtl

ILLDeadlines for proposal submission: 19 September 2006www.ill.fr

IRIDeadlines for proposal submission: Anytime during 2006www.rid.tudelft.nl/live/pagina.jsp?id=b15d7df9-7928-441e-b45d-6ecce78d6b0e&lang=en

ISISDeadlines for proposal submission: 15th March 2006www.isis.rl.ac.uk

LLB-ORPHEE-SACLAYDeadlines for proposal submission: 1 October 2006www-llb.cea.fr

NPLDeadlines for proposal submission: 15th September 2006www.omega.ujf.cas.cz/CFANR/access.html

SINQDeadlines for proposal submission: 15th Novembre 2006http://sinq.web.psi.ch/

Call for proposals forSynchrotron Radiation Sourceshttp://www.lightsources.org/cms/?pid=1000336#byfacility

ALSDeadlines for proposal submission: 5th June 2006www-als.lbl.gov/als/quickguide/independinvest.html

APSDeadlines for proposal submission: 14 July 2006www.aps.anl.gov/Users/Scientific_Access/General_User/GUP_Calendar.

BESSYDeadlines for proposal submission: 15th August 2006www.bessy.de/boat/

CHESSDeadlines for proposal submission: 31st October 2006www.chess.cornell.edu/prposals/index.htm

CNMDeadlines for proposal submission: 14th July 2006http://nano.anl.gov/users/index.html

DARESBURYDeadlines for proposal submission: 1st November 2006www.srs.ac.uk/srs/userSR/user_access2.html

ELETTRADeadlines for proposal submission: 31st August 2006www.elettra.trieste.it/UserOffice/index.php?n=Main.ApplicationForBeamtime

ESRFDeadlines for proposal submission: 1st September 2006www.esrf.fr

FELIXDeadlines for proposal submission: 1st December 2006www.rijnh.nl/molecular-and-laser-physics/felix/n4/f1234.htm

HASYLABDeadlines for proposal submission: 1st September 2006www.hasylab.desy.de/user_infos/projects/3_deadlines.htm

MAX-LABDeadline for proposal submission: July 2006www.maxlab.lu.se

NSLSDeadlines for proposal submission: 31st September 2006www.nls.bnl.gov/

SLSDeadlines for proposal submission: 15th September and15th October 2006http://sls.web.psi.ch/view.php/users/experiments/proposals/opencalls/index.html

SRCDeadlines for proposal submission: 1st August 2006

SSRLDeadlines for proposal submission: 1st July, 14th August,28th August, 1st December 2006www.ssrl.slac.stanford.edu/users/user_admin/deadlines.html

40


CALENDAR

July 6 – 8, 2006 HYOGO, JAPAN

SRPS3 - Synchrotron Radiation in Polymer Science IIILecture Hall in Public Relations Centerhttp://www.spring8.or.jp/en/users/meeting/2006/srps3

July 9 - 13, 2006 KYOTO, JAPAN

SAS2006 Kyoto – 13th International Conference onSmall-Angle ScatteringKyoto International Conference Hallhttp://sas2006.scphys.kyoto-u.ac.jp/

July 9 – 14, 2006 STANFORD, CA, USA

XAFS13 - 13th International Conference on X-rayAbsorption Fine StructureStanford University campus.http://www-ssrl.slac.stanford.edu/xafs13/

July 10 – 11, 2006 ZÜRICH, SWITZERLAND

Nanoanalysis - CEAC Summer WorkshopHG E 1.1, ETH Zentrum, 8092 Zürichhttp://www.ceac.ethz.ch/Ceac/Workshop.html

July 11 – 12, 2006 CHILTON, UK

PhotoEmission Electron Microscopy (PEEM) WorkshopDiamond Light Sourcehttp://www.diamond.ac.uk/News/LatestEvents/PEEMworkshop.htm

July 12 – 18, 2006 MANCHESTER, UK

EPS-HEP2007 - European Physical Society Conference onHigh Energy Physicshttp://www.hep.man.ac.uk/HEP2007/

July 14 2006 GARCHING, GERMANY

Workshop Neutrons for Geoscience Faculty for Mechanical Engineeringhttp://www.new.frm2.tum.de/en/events/konferenzen.html

July 16 – 20, 2006 TAIPEI, TAIWAN

9SXNS - Ninth International Conference on Surface X-Ray and Neutron Scatteringhttp://web11.nsrrc.org.tw/9sxns/

July 17 – 21, 2006 YEREVAN, ARMENIA

Brilliant Light Facilities and Research in Life andMaterial SciencesNATO Advanced Research Workshop (ARW)http://www.candle.am/ARW06/

July 22 – 27, 2006 HONOLULU, HAWAII, USA

ACA 2006 - The 2006 Meeting of the AmericanCrystallographic Associationhttp://www.xray.chem.ufl.edu/aca2006/index.html

July 23 – 26, 2006 PILANESBERG, SOUTH AFRICA

2nd International Conference on Diamond for ModernLight Sources Kwa Maritane Bush Lodgehttp://hermes.wits.ac.za/www/Conferences/diamond/index.htm

July 30 – Aug 2, 2006 CHICAGO, IL, USA

SRMS-5 - Fifth International Conference on SynchrotronRadiation in Materials ScienteThe Drake Hotelhttp://www.aps.anl.gov/News/Conferences/2006/SRMS/index.html

Aug 5 - 9, 2006 SAN DIEGO, CA, USA

20th Annual Symposium of The Protein Societye-mail: [email protected]://www.proteinsociety.org/pages/page00g.htm

Aug 19 - 26, 2006 ZUOZ, SWITZERLAND

4th PSI Summer School on Condensed Matter Research:‘Neutron, X-ray and Muon studies of nano scalestructures’Lyceum Alpinume-mail: [email protected]://num.web.psi.ch/zuoz2006/

Aug 27 – Sept 1, 2006 BERLIN, GERMANY

FEL2006 - 28th International Free Electron LaserConferencee-mail: [email protected]://www.bessy.de/fel2006

Aug 28 – Sept 1, 2006 FOZ DO IGUAÇU, BRAZIL

ICESS 10International Conference on Electronic Spectroscopy andStructure http://www.lnls.br/icess10

Aug 31 – Sept 9, 2006 JACA, SPAIN

International Summer School on “Neutron Techniques inMolecular Magnetism”e-mail: [email protected]://magmanet.unizar.es/

41


CALENDAR

Sept 4 – 6, 2006 RIO DE JANEIRO, BRAZIL

SCASM - International Symposium: Scattering,Coincidence and Absorption Studies of MoleculesFederal Universityhttp://server2.iq.ufrj.br/~scasm2006

Sept 4 - 8, 2006 PARIS, FRANCE

ECOSS-24 - 24th European Conference on Surface Sciencehttp://www.iuvsta.org/ecoss.html

Sept 10 - 13, 2006 JACA, SPAIN

III Meeting of the Spanish Society of Neutron Techniqueshttp://www.unizar.es/magmanet/summerschool/

Sept 10 - 14, 2006 SAN FRANCISCO, CA, USA

232nd American Chemical Society MeetingMoscone Centerhttp://www.chemistry.org/portal/a/c/s/1/acsdisplay.html?DOC=meetings\sanfrancisco2006\home.html

Sept 12 – 13, 2006 CHILTON, OXFORDSHIRE, UK

Diamond Light Source Users’ MeetingDiamond Light Source, Harwell Science and InnovationCampushttp://www.diamond.ac.uk/ForUsers/SRUser06/default.htm

Sept 13 – 15, 2006 BREMEN, GERMANY

7th European Conference on Residual Stresses (ECRS7)AWTE-mail: [email protected]://www.ecrs7.de/

Sept 14 – 15, 2006 GRENOBLE, FRANCE

Theoretical Concepts on Magnetism in Solids SymposiumESRFhttp://www.esrf.fr/NewsAndEvents/Conferences/PaoloCarraSymposium

Sept 17 – 21, 2006 RATHEN, GERMANY

NSS4 - 4th International Workshop on NanoscaleSpectroscopy and Nanotechnologye-mail:[email protected]://www.bessy.de/cms.php?idcat=184&changelang=5

Sept 18 - 22, 2006 SHANGAI, P.R. China

IRMMW/ THz 2005 - Joint 31st International Conference onInfrared and Millimeter Waves and 14th InternationalConference on Terahertz ElectronicsHotel Equatorial Shanghaie-mail: [email protected]

[email protected]://www.sitp.ac.cn/irmmw-thz2006

Sept 19 - 22, 2006 KARLSRUHE, GERMANY

XTOP 2006 - 8th Biennial Conference on High ResolutionX-Ray Diffraction and ImagingSteigenberger Hotel Badischer Hofhttp://xtop2006.fzk.de

Sept 19 - 22, 2006 BERLIN, GERMANY

Polarised Neutron SchoolLeibniz-Saalhttp://www.hmi.de/bensc/pncmi2006

Sept 25 - 27, 2006 LUND, SWEDEN

FASM 19th Users’ Meeting at MAX-labHotel Scandic Star.http://www2.maxlab.lu.se/meeting/um/index.jsp


Polarised Neutrons in Condensed Matter Investigations,PNCMI 2006Leibniz-Saale-mail: [email protected]://www.hmi.de/bensc/pncmi2006

Sept 25 – Oct 6, 2006 S. MARGHERITA DI PULA, ITALY

VIII International School of Neutron Scattering“Francesco Paolo Ricci” - Neutron Scattering FromMagnetic SystemsHotel Flamingohttp://www.fis.uniroma3.it/sns_fpr/

Sept 27 – 29, 2006 BERLIN, GERMANY

SR2A - Synchrotron Radiation in Arts and ArchaeologyWorkshopBerlin Adlershofhttp://www.bessy.de/cms.php?idcat=176

CALENDAR

42


Sept 28 – 29, 2006 VILLIGEN, PSI, SWITZERLAND

SLS Users’ MeetingPaul Scherrer Institutee-mail: [email protected]://sls.web.psi.ch/view.php/users/affairs/umeetings/Umee2006/index.html


The 3rd workshop on Inelastic Neutron Spectrometers 2006SpreePalais am Domhttp://www.hmi.de/bensc/wins2006/main.html

Oct 2 - 4, 2006 VILLIGEN, SWITZERLAND

International Workshop on Applications of AdvancedMonte Carlo Simulations in Neutron ScatteringPaul Scherrer Institutehttp://lns00.psi.ch/mcworkshop/

Oct 3 – 4, 2006 HSINCHU, TAIWAN

NSRRC Users’ Meetinghttp://users.nsrrc.org.tw/meeting/index-en.htm

Oct 4 - 6, 2006 HAMBURG, GERMANY

German Conference for Research with SynchrotronRadiation, Neutrons and Ion Beams at Large Facilities 2006Hamburg Universityhttp://www.sni2006.de/

Oct 9 - 10, 2006 KARLSRUHE, GERMANY

ANKA Users’ MeetingForschungszentrumhttp://ankaweb.fzk.de/conferences/users-meeting-2006/

Oct 23 - 25, 2006 OAK RIDGE, USA

Workshop on Imaging and Neutrons (IAN2006)Oak Ridge National Laboratoryhttp://www.sns.gov/workshops/ian2006/

Nov 6 – 10, 2006 BARILOCHE, ARGENTINA

13th International Conference on Solid Films and SurfacesPanamericano Hotelhttp://www.cab.cnea.gov.ar/icsfs-13/

Nov 22 – 24, 2006 GRENOBLE, FRANCE

ILL Soft Matter User MeetingILLhttp://www.ill.fr/softill2006/ILL%20soft%20Matter%20User%20Meeting/Homepage.html

Nov 24 – 25, 2006 KEK, TSUKUBA, JAPAN

AOF2006 - First Asian/Oceanic Forum for SynchrotronRadiation ResearchBuilding No.3 Seminar Hallhttp://pfwww.kek.jp/AOF2006/index.html

Nov 27 – 29, 2006 CAIRO, EGYPT

5th SESAME Users’ Meetinghttp://www.cu.edu.eg/science/sesame/Tentative_Program.htm

Dec 7 - 8, 2006 SAN FRANCISCO, CA, USA

Neutron Scattering applied to Earth SciencesFall 2006 American Geophysical Unionhttp://www.minsocam.org/MSA/SC/Neutron_descrptn.html

Dec 13 - 15, 2006 GRENOBLE, FRANCE

Dynamics of Molecules and MaterialsILLhttp://www.ill.fr/Events/DMM/

43


BENSC Berlin Neutron Scattering CenterHahn-Meitner-InstitutGlienicker Strasse 100D-14109 Berlin, GermanyTel: ~49/30/8062-2778; Fax: ~49/30/8062-2523E-mail: [email protected]://www.hmi.de/bensc/index_en.html

Budapest Neutron CentreBudapest Research ReactorType: Reactor. Flux: 2.0 x 1014 n/cm2/sAddress for application forms:Dr. Borbely SándorKFKI Building 10,1525 Budapest - Pf 49, HungaryE-mail: [email protected]://www.iki.kfki.hu/nuclear

CNFCanadian Neutron Beam CentreNational Research Council of CanadaBuilding 459, Station 18Chalk River LaboratoriesChalk River, OntarioCANADA K0J 1J0Tel: 1- (888) 243-2634 (toll free) / 1- (613) 584-8811 ext. 3973Fax: 1- (613) 584-4040http://cnf-ccn.gc.ca/home.html

FRG-1 Geesthacht (D)Type: Swimming Pool Cold Neutron Source.Flux: 8.7 x 1013 n/cm2/sAddress for application forms and informations:Reinhard Kampmann, Institute for Materials Science,Div. Wfn-Neutronscattering, GKSS, Research Centre,21502 Geesthacht, GermanyTel: +49 (0)4152 87 1316/2503; Fax: +49 (0)4152 87 1338E-mail: [email protected]://www.gkss.de

HFIROak Ridge National Lab.Oak Ridge, USATel: (865)574-5231; Fax: (865)576-7747E-mail: [email protected]://neutrons.ornl.gov/

HMI Berlin BER-II (D)Facility: BER II, BENSCType: Swimming Pool Reactor. Flux: 2 x 1014 n/cm2/sAddress for application forms:Dr. Rainer Michaelsen, BENSC,Scientific Secretary, Hahn-Meitner-Institut,

Glienicker Str 100, 14109 Berlin, GermanyTel: +49 30 8062 2304/3043; Fax: +49 30 8062 2523/2181E-mail: [email protected]://www.hmi.de/bensc

IBR2 Fast Pulsed Reactor Dubna (RU)Type: Pulsed Reactor.Flux: 3 x 1016 (thermal n in core)Address for application forms:Dr. Vadim Sikolenko,Frank Laboratory of Neutron PhysicsJoint Institute for Nuclear Research141980 Dubna, Moscow Region, Russia.Tel: +7 09621 65096; Fax: +7 09621 65882E-mail: [email protected]://nfdfn.jinr.ru/flnph/ibr2.html

ILL Grenoble (F)Type: 58MW High Flux Reactor.Flux: 1.5 x 1015 n/cm2/sScientific CoordinatorDr. G. Cicognani, ILL, BP 156,38042 Grenoble Cedex 9, FranceTel: +33 4 7620 7179; Fax: +33 4 76483906E-mail: [email protected] and [email protected]://www.ill.fr

IPNS Intense Pulsed Neutron at Argonne (USA)for proposal submission by e-mailsend to [email protected] or mail/fax to:IPNS Scientific Secretary, Building 360Argonne National Laboratory,9700 South Cass Avenue, Argonne,IL 60439-4814, USAPhone: 630/252-7820; Fax: 630/252-7722 http://www.pns.anl.gov/

ISIS Didcot (UK)Type: Pulsed Spallation Source.Flux: 2.5 x 1016 n fast/sAddress for application forms:ISIS Users Liaison Office, Building R3,Rutherford Appleton Laboratory, Chilton,Didcot, Oxon OX11 0QXTel: +44 (0) 1235 445592; Fax: +44 (0) 1235 445103E-mail: [email protected]://www.isis.rl.ac.uk

JAERI (J)Japan Atomic Energy Research Institute,Tokai-mura, Naka-gun,Ibaraki-ken 319-11, Japan.Jun-ichi Suzuki (JAERI);

N E U T R O N S O U R C E SNEUTRON SCATTERING WWW SERVERS IN THE WORLD(http://neutron.neutron-eu.net/n_news/n_calendar_of_events)

FACILITIES

FACILITIES

44


Yuji Ito (ISSP, Univ. of Tokyo);Fax: +81 292 82 59227; Telex: JAERIJ24596http://www.ndc.tokai.jaeri.go.jp/

JEEP-II Kjeller (N)Type: D2O moderated 3.5%enriched UO2 fuel.Flux: 2 x 1013 n/cm2/sAddress for application forms:Institutt for EnergiteknikkK.H. Bendiksen, Managing DirectorBox 40, 2007 Kjeller, NorwayTel: +47 63 806000, 806275; Fax: +47 63 816356E-mail: [email protected]://www.ife.no

KENSInstitute of Materials Structure ScienteHigh Energy Accelerator research Organisation1-1 Oho, Tsukuba-shi, Ibaraki-ken,?305-0801, JAPANE-mail: [email protected]://neutron-www.kek.jp/index_e.html

KURKyoto University Research Reactor Institute,Kumatori-cho Sennan-gun,Osaka 590-0494,JapanTel::+81-72-451-2300Fax:+81-72-451-2600http://www.rri.kyoto-u.ac.jp/en/

LANSCELos Alamos Neutron Sciente CenterTA-53, Building 1, MS H831Los Alamos National Lab, Los Alamos, USA505-665-8122E-mail: [email protected]://www.lansce.lanl.gov/index.html

LLB Orphée Saclay (F)Type: Reactor. Flux: 3.0 x 1014 n/cm2/sLaboratoire Léon Brillouin (CEA-CNRS)E-mail: [email protected]://www-llb.cea.fr/index_e.html

NIST Center for Neutron Research (USA)National Institute of Standards and Technology100 Bureau Drive, MS 8560Gaithersburg, MD 20899-8560Patrick Gallagher, Directortel: (301) 975-6210fax: (301) 869-4770E-email: [email protected]://www.ncnr.nist.gov/call/current_call.html

NRI Rez (CZ)Type: 10 MW research reactor.Address for informations:Zdenek Kriz, Scientif SecretaryNuclear Research Institute Rez plc,

250 68 Rez - Czech RepublicTel: +420 2 20941177 / 66173428; Fax: +420 2 20941155E-mail: [email protected] and [email protected]://www.nri.cz

NRU Chalk River LaboratoriesThe peak thermal flux 3x1014 cm-2 sec-1Neutron Program for Materials Research National Research Council Canada Building 459, Station 18 Chalk River Laboratories Chalk River, Ontario - Canada K0J 1J0Phone: 1 - (888) 243-2634 (toll free)Phone: 1 - (613) 584-8811 ext. 3973Fax: 1- (613) 584-4040http://neutron.nrc-cnrc.gc.ca/home.html

PSI-SINQ Villigen (CH)Type: Steady spallation source.Flux: 2.0 x 1014 n/cm2/sContact address: Paul Scherrer InstitutUser Office, CH-5232 Villigen PSI - SwitzerlandTel: +41 56 310 4666; Fax: +41 56 310 3294E-mail: [email protected]://sinq.web.psi.ch

RID Reactor Institute Delft (NL)Type: 2MW light water swimming pool.Flux: 1.5 x 1013 n/cm2/sAddress for application forms:Dr. M. Blaauw, Head of Facilities and Services Dept.Reactor Institute Delft, Faculty of Applied SciencesDelft University of Technology, Mekelweg 152629 JB Delft, The NetherlandsTel: +31-15-2783528Fax: +31-15-2788303E-mail: [email protected]://www.rid.tudelft.nl

SPALLATION NEUTRON SOURCE, ORNL (USA)Address for information:A. E. Ekkebus,Spallation Neutron Source, Oak Ridge National LaboratoryOne Bethel Valley Road, Bldg 8600P. O. Box 2008, MS 6460Oak Ridge, TN 37831 - 6460Tel: 089 289 14701; Fax: 089 289 14666http://www.sns.gov/

TU Munich FRM, FRM-2 (D)Type: Compact 20 MW reactor.Flux: 8 x 1014 n/cm2/sAddress for information:Prof. Winfried Petry,FRM-II Lichtenbergstrasse 1 - 85747 GarchingTel: 089 289 14701; Fax: 089 289 14666E-mail: [email protected]://www.frm2.tu-muenchen.de

FACILITIES

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ALBA - Synchrotron Light FacilityCELLS - ALBA, Edifici Ciències. C-3 central. CampusUABCampus Universitari de Bellaterra. UniversitatAutònoma de Barcelona08193 Bellaterra, Barcelona, Spaintel: +34 93 592 43 00 ?- fax: +34 93 592 43 01 http://www.cells.es/

ALS Advanced Light SourceBerkeley Lab, 1 Cyclotron Rd, MS6R2100, Berkeley,CA 94720tel: +1 510.486.7745 - fax: +1 510.486.4773E-mail: [email protected]://www-als.lbl.gov/

ANKAForschungszentrum Karlsruhe Institut fürSynchrotronstrahlungHermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germanytel: +49 (0)7247 / 82-6071 - fax: +49-(0)7247 / 82-6172E-mail: [email protected]://hikwww1.fzk.de/iss/

APS Advanced Photon SourceArgonne Nat. Lab. 9700 S. Cass Avenue, Argonne, Il60439, USAtel: (630) 252-2000 - fax: +1 708 252 3222http://www.aps.anl.gov

ASTRIDISA, Univ. of Aarhus, Ny Munkegade, DK-8000 Aarhus,Denmarktel: +45 61 28899 - fax: +45 61 20740http://www.aau.dk/uk/nat/isa

AS Australian SynchrotronLevel 17, 80 Collins St_Melbourne VIC 3000_Australiatel: +61 3 9655 3315 - fax: +61 3 9655 8666E-mail: [email protected]://www.synchrotron.vic.gov.au

BESSY Berliner Elektronenspeicherring Gessellschaft.fürSynchrotronstrahlungBESSY GmbH, Albert-Einstein-Str.15, 12489 Berlin,Germanytel +49 (0)30 6392-2999 - fax: +49 (0)30 6392-2990E-mail: [email protected]://www.bessy.de

BSRF Beijing Synchrotron Radiation FacilityBEPC National Laboratory, Institute of High EnergyPhysics, Chinese Academy of SciencesP.O.Box 918, Beijing 100039, P.R. Chinatel: +86-10-68235125 - fax: +86-10-68222013E-mail: [email protected]://www.ihep.ac.cn/bsrf/english/main/main.htm

CANDLE Center for the Advancement of Natural Discoveriesusing Light EmissionAcharyan 31 ?375040, Yerevan, Armeniatel/fax: +374-1-629806E-mail: [email protected]://www.candle.am/index.html

CAMD Center Advanced Microstructures & DevicesCAMD/LSU 6980 Jefferson Hwy., Baton Rouge, LA70806, USAtel: +1 (225) 578-8887 - fax : +1 (225) 578-6954E-mail: [email protected]://www.camd.lsu.edu/

CHESS Cornell High Energy Synchrotron SourceCornell High Energy Synchrotron Source200L Wilson Lab, Rt. 366 & Pine Tree Road, Ithaca, NY14853, USATel: +1 (607) 255-7163, +1 (607) 255-9001E-mail: [email protected]://www.tn.cornell.edu/

CLS Canadian Light SourceCanadian Light Source Inc., University of Saskatchewan101, Perimeter Road Saskatoon, SK., Canada. S7N 0X4tel: (306) 657-3500 - fax: (306) 657-3535E-mail: [email protected]://www.lightsource.ca

DAFNE LightINFN – LNFVia Enrico Fermi, 40, I-00044 Frascati (Rome), Italyfax: +39 6 94032597www.lnf.infn.it/esperimenti/sr_dafne_light/

DELSY Dubna ELectron SYnchrotronJINR Joliot-Curie 6, 141980 Dubna, Moscow region,Russiatel: + 7 09621 65 059 - fax: + 7 09621 65 891E-mail:[email protected] http://www.jinr.ru/delsy/

S Y N C H R OT R O N R A D I AT I O N S O U R C E SSYNCHROTRON SOURCES WWW SERVERS IN THE WORLD(http://www.esrf.fr/navigate/synchrotrons.html)

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DELTA Dortmund Electron Test Accelerator - FELICITA I (FEL)Institut für Beschleunigerphysik undSynchrotronstrahlung, Universität DortmundMaria-Goeppert-Mayer-Str. 2 44221 Dortmund,Germanyfax: +49-(0)231-755-5383www.delta.uni-dortmund.de/home_e.html

DFELL Duke Free Electron Laser LaboratoryDuke Free Electron Laser Laboratory PO Box 90319, Duke University Durham, North Carolina27708-0319, USAtel: +1 (919) 660-2666 - fax: +1 (919) 660-2671E-mail: [email protected]/

Diamond Light SourceDiamond Light Source LtdDiamond House, Chilton, Didcot, OXON OX11 0DE, UKtel: +44 (0)1235 778000 fax: +44 (0)1235 778499E-mail: [email protected] www.diamond.ac.uk/

ELETTRA Synchrotron Light Lab.Sincrotrone Trieste S.C.p.AStrada Statale 14 - Km 163,5 in AREA Science Park, 34012Basovizza, Trieste, Italytel: +39 40 37581 fax: +39 (040) 938-0902E-mail: [email protected]

ELSA Electron Stretcher AcceleratorPhysikalisches Institut der Universität BonnBeschleunigeranlage ELSA, Nußallee 12, D-53115 Bonn,Germanytel: +49-228-735926 - fax +49-228-733620 E-Mail: [email protected]/elsa-facility_en.html

ESRF European Synchrotron Radiation Lab.ESRF, 6 Rue Jules Horowitz, BP 220, 38043 GrenobleCedex 9, FRANCE tel: +33 (0)4 7688 2000 fax: +33 (0)4 7688 2020E mail: [email protected]/

FELBE Free-Electron Lasers at the ELBE radiation source atthe FZR/DresdenBautzner Landstrasse 128 _01328 Dresden, Germanywww.fz-rossendorf.de/pls/rois/Cms?pNid=471

FELIXFree Electron Laser for Infrared eXperimentsFOM Institute for Plasma Physics ‘Rijnhuizen’Edisonbaan, 14, 3439 MN Nieuwegein, The NetherlandsP.O. Box 1207, 3430 BE Nieuwegein, The Netherlandstel: +31-30-6096999 fax: +31-30-6031204E-mail: [email protected]/felix/

HASYLAB Hamburger Synchrotronstrahlungslabor - DORISIII, _PETRA II / III, FLASHDESY - HASYLAB Notkestrasse 85 22607 Hamburg, Germanytel: +49 40 / 8998-2304 - fax: +49 40 / 8998-2020E-mail: [email protected]/

HSRC Hiroshima Synchrotron Radiation Center - HiSOR Hiroshima University2-313 Kagamiyama, Higashi-Hiroshima, 739-8526, Japantel: +81 82 424 6293 fax: +81 82 424 6294www.hsrc.hiroshima-u.ac.jp/index.html

iFELInstitute of Free Electron Laser, Graduate School ofEngineering, Osaka University2-9-5 Tsuda-Yamate, Hirakata, Osaka 573-0128, Japantel: +81-(0)72-897-6410www.fel.eng.osaka-u.ac.jp/english/index_e.html

INDUS -1 / INDUS -2 Centre for Advanced Technology Department of AtomicEnergy Government of IndiaP.O : CAT Indore _M.P - 452 013 _India tel: +91-731-248-8003 _- fax: 91-731-248-8000E-mail: [email protected] http://www.ee.ualberta.ca/~naik/accind1.html

IR FEL Research Center - FEL-SUTIR FEL Research Center, Research Institutes for Scienceand TechnologyThe Tokyo University of Sciente, Yamazaki 2641, Noda,Chiba 278-8510, Japantel: +81 4-7121-4290 - fax: +81 4-7121-4298E-mail: [email protected]/~felsut/english/index.htm

ISA Institute for Storage Ring Facilities - ASTRID-1ISA, University of Aarhus, Ny Munkegade, bygn. 520,DK-8000 Aarhus C, Denmarktel: +45 8942 3778 - fax: +45 8612 0740E-mail: [email protected]/

ISI-800Institute of Metal PhysicsNational Academy of Sciences of Ukrainetel: +(380) 44 424-1005 - fax: +(380) 44 424-2561E-mail:[email protected]

Jlab - Jefferson Lab FEL12000 Jefferson Avenue,Newport News, Virginia 23606, USAtel: (757) 269-7767www.jlab.org/FEL

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Kharkov Institute of Physics and Technology - PulseStretcher/Synchrotron RadiationNational Science Center, KIPT, 1, Akademicheskaya St.,Kharkov, 61108, Ukrainetel: 38 (057) 335-35-30 - fax: 38 (057) 335-16-88www.kipt.kharkov.ua

KEK Photon FactoryNat. Lab. for High Energy Physics, 1-1, Oho,Tsukuba-shi Ibaraki-ken, 305 Japantel: +81 298 641171 - fax: +81 298 642801www.kek.jp/

KSR Nuclear Science Research Facility - AcceleratorLaboratoryGokasho,Uji, Kyoto 611fax: +81-774-38-3289wwwal.kuicr.kyoto-u.ac.jp/www/index-e.htmlx

KSRS Kurchatov Synchrotron Radiation Source KSRS -Siberia-1 / Siberia-2Kurtchatov Institute 1, Kurtchatov Sq.,Moscow 123182, Russia www.kiae.ru/eng/wel/alb/illus6.htm

LCLS Linac Coherent Light SourceStanford Linear Accelerator Center (SLAC)2575 Sand Hill Road, MS 18 ?Menlo Park, CA 94025?USAtel: +1 (650) 926-3191 - fax: +1 (650) 926-3600E-mail: [email protected] www-ssrl.slac.stanford.edu/lcls/

LNLS Laboratorio Nacional de Luz SincrotronCaixa Postal 6192, CEP 13084-971, Campinas, SP, Braziltel: +55 (0) 19 3512-1010 - fax: +55 (0)19 3512-1004E-mail: [email protected] www.lnls.br/

LURE Laboratoire pour l’utilisation du RayonnementElectromagnétiqueBât 209D Centre Universitaire Paris-Sud, B.P. 34 - 91898Orsay Cedex, Francetel: +33 (0)1 6446 8000E-mail: [email protected]

MAX-LabBox 118, University of Lund, S-22100 Lund, Swedentel: +46-222 9872 - fax: +46-222 4710www.maxlab.lu.se/

Medical Synchrotron Radiation FacilityNational Institute of Radiological Sciences (NIRS)4-9-1, Anagawa, Inage-ku, Chiba-shi, 263-8555, Japantel: +81-(0)43-251-2111www.lightsources.org/cms/?pid=1000161

NSLS National Synchrotron Light SourceNSLS User Administration OfficeBrookhaven National Laboratory, P.O. Box 5000, Bldg.725B, Upton, NY 11973-5000, USAtel: +1 (631) 344-7976 - fax: +1 (631) 344-7206 E-mail: [email protected] www.nsls.bnl.gov/

NSRL National Synchrotron Radiation Lab.University od Sciente and Technology China (USTC)Hefei, Anhui 230029, PR Chinatel +86-551-5132231,3602034 - fax: +86-551-5141078E-mail: [email protected]/en/enhome.html

NSRRC National Synchrotron Radiation Research CenterNational Synchrotron Radiation Research Center 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu30076, Taiwan, R.O.C.tel: +886-3-578-0281 - E-mail: [email protected]/

NSSR Nagoya University Small Synchrotron Radiation FacilityNagoya University4-9-1,Anagawa, Inage-ku, Chiba-shi, 263-8555 Japantel: +81-(0)43-251-2111http://nssr.xtal.nagoya-u.ac.jp

PAL Pohang Accelerator Lab.San-31 Hyoja-dong Pohang, Kyungbuk 790-784, Koreatel: +82 562 792696 - fax: +82 562 794499http://pal.postech.ac.kr/eng/index.html

PF Photon FactoryKEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japantel: +81 (0)-29-879-6009 - fax: +81 (0)-29-864-4402E-mail: [email protected]://pfwww.kek.jp/

RitS Ritsumeikan University SR Center - MIRRORCLE6X/MIRRORCLE 20Ritsumeikan University (RitS) SR Center,Biwako-Kusatsu CampusNoji Higashi 1-chome, 1-1 Kusatsu, 525-8577 Shiga-ken,Japantel: +81 (0)77 561-2806 - fax: +81 (0)77 561-2859E-mail:[email protected]/acd/re/src/index.htm

SESAME Synchrotron-light for Experimental Science andApplications in the Middle EastE-mail: [email protected]/

SLS Swiss Light SourcePaul Scherrer Institut reception building, PSI West, CH-5232 Villigen PSI, Switzerlandtel: +41 56 310 4666 - fax: +41 56 310 3294E-mail [email protected]://sls.web.psi.ch

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SPring-8Japan Synchrotron Radiation Research Institute (JASRI)Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japantel: +81-(0) 791-58-0961 _- fax: +81-(0) 791-58-0965E-mail: [email protected]/en/

SOLEILSynchrotron SOLEILL’Orme des Merisiers Saint-Aubin - BP 48 91192 GIF-sur-YVETTE CEDEX,FRANCEtel: +33 1 6935 9652 _- fax: +33 1 6935 9456E-mail: frederique.fraissard@synchrotron-soleil.frwww.synchrotron-soleil.fr/anglais/index.html

SOR-RINGInstitute for Solid State PhysicsS.R. Lab, Univ. of Tokyo, 3-2-1 Midori-cho Tanashi-shi,Tokyo 188, Japantel: +81 424614131 - fax: +81 424615401

SRC Synchrotron Radiation CenterUniv.of Wisconsin at Madison, 3731 Schneider Drive,Stoughton, WI 53589-3097 USAtel: +1 (608) 877-2000 - fax: +1 (608) 877-2001www.src.wisc.edu

SSLS Singapore Synchrotron Light Source –Helios IINational University of Singapore (NUS)Singapore Synchrotron Light Source, NationalUniversity of Singapore5 Research Link, Singapore 117603, Singaporetel: (65) 6874-6568 - fax: (65) 6773-6734http://ssls.nus.edu.sg/index.html

SSRC Siberian Synchrotron Research Centre – VEPP3/VEPP4Lavrentyev av. 11, Budker INP, Novosibirsk 630090,Russiatel: +7(3832)39-44-98 - fax: +7(3832)34-21-63E-mail: [email protected]://ssrc.inp.nsk.su/

SSRL Stanford Synchrotron Radiation Lab.Stanford Linear Accelerator Center, 2575 Sand Hill Road,Menlo Park, CA 94025, USAtel: +1 650-926-4000 - fax: +1 650-926-3600E-mail: [email protected]

SRS Synchrotron Radiation SourceCCLRC Daresbury Lab.Warrington, Cheshire, WA4 4AD, U.K.tel: +44 (0)1925 603223 - fax: +44 (0)1925 603174E-mail: [email protected]/srs/

Super SOR Light SourceKashiwa Campus, Univ. of TokyoSRL Experimental Hall (Super SOR Project Office)5-1-5 KashiwanoHa, Kashiwa-shi, Chiba 277-8581, Japantel: +81 (0471) 36-3405 - fax: +81(0471) 34-6083Kashiwa Campus, Univ. of Tokyowww.issp.u-tokyo.ac.jp/labs/sor/project/MENU.html

SURF-II / SURF-III Synchrotron Ultraviolet Radiation FacilityNIST, 100 Bureau Drive, Stop 3460 _Gaithersburg, MD20899-3460, USAtel: +1 301 975 6478http://physics.nist.gov/MajResFac/surf/surf.html

TNK - F.V. Lukin InstituteState Research Center of Russian Federation103460, Moscow, Zelenogradtel. +7(095) 531-1306 / +7(095) 531-1603 - fax: +7(095)531-4656

TSRF Tohoku Synchrotron Radiation Facilità - Laboratory ofNuclear ScienteTohoku UnivdersityTel: +81 (022)-743-3400 _- fax: +81 (022)-743-3401E-mail: [email protected]/index.php

UVSOR Ultraviolet Synchrotron Orbital Radiation FacilityUVSOR Facility, Institute for Molecular Sciente,Myodaiji, Okazaki 444-8585, Japanhttp://www.uvsor.ims.ac.jp/defaultE.htm

VU FEL W. M. Keck Vanderbilt Free-electron Laser Center410 24th Avenue Nashville, TN 37212 Box 1816, Stn BNashville, TN 37235, USAwww.vanderbilt.edu/fel/

NOTIZIARIO Neutroni e Luce di Sincrotrone - Issue 11 n.2, 2006

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