ISOL@MYRRHA

ISOL@MYRRHA

Dieter Pauwels

K.U. LeuvenInstituut voor Kern- en Stralingsfysica

D. Pauwels ISOLDE seminar November 11, 2010 CERN

An Isotope Separator On-Line facility coupled to theMYRRHA high-intensity proton accelerator

Outline


• The MYRRHA project in Mol, Belgium

• ISOL@MYRRHA: an ISOL facility coupled to the MYRRHA proton driver

• ISOL@MYRRHA: examples of unique research opportunities

• Conclusions

Lead-Bismuth coolant

Sub-critical reactorAccelerator (600 MeV proton, 4 mA)

The MYRRHA concept (SCK•CEN, Mol, Belgium)

ADS “Accelerator Driven System”

Neutron multiplier

Fastneutronsource

Waste transmutation

Material testing

others: RI, NTD-Si,...

Flexible irradiation facility

Spallation source( proton neutron )• Cost: 960 M€ (40% contribution from Belgium)

• Timeline:

• 2010 – 2015: detailed engineering, tenders, testing, licensing

• 2015 – 2022: construction, assembling, commissioning

• 2022 – 2024: progressive MYRRHA start-up to full-power operation


100 ms

100 ms

An ISOL facility coupled to MYRRHA: ISOL@MYRRHA

RFQ DTL

Super-conducting section

Spoke cavities 350 MHz

Elliptical cavities: 700 MHz, 3 sections

~0.1 3-5 ~20 ~100 ~200 ~500

1 GeV

600

Ion Source

H+

Magnetic kicker

E (MeV)

MYRRHA

100-200 mA, ~DC

Low-resolution mass separator

RFQ cooler and buncherHigh-resolution

mass separator

Unique opportunities for:

• Fundamental interactions

• Solid-state physics

• Nuclear physics

• Atomic physics

• Radio-pharmaceuticals

Ruggedized target: SiC/C, TiC/C, ZrC/C, La, Ta, UC/C

Sustainable 1+ ion source: Surface Ion., ECR, RILIS

ISOL@MYRRHA

2-4 ms

Proton duty cycle

t0

I0

I

3.8-3.9 mA, ~DC

4 mA, DC

• I=4 mA (DC), E=600 MeV (upgradeable to 1 GeV)

• <5 trips (>1s) per 3 months (=extremely high reliability)

• Short beam-off time periods (100 ms) for diagnostics purposes


ISOL@MYRRHA: technical options

• Ruggedized target materials• Ruggedized: Carbide (e.g., SiC/C, UC/C, …) or metal (e.g., Nb, Ta, …) targets• Including UC/C: workhorse targets at present

• Ruggedized target-ion source systems delivering ~50-keV RIB:• ECR 1+: gaseous elements (noble gases, C, N, O,..))• Surface ion source (hot cavity): alkaline and earth alkaline elements• Laser ion sources

• “Green field” facility at a nuclear site (SCK•CEN):• optimal lay-out of the facility: pre-separator – RF-cooler – post-separator (mass resolution: M/DM > 10000)• multiple ion beams simultaneously : limited mass range for same element • specific experimental hall requirements (e.g. neutron detection hall, vibration free laboratory, low-

background room)

Element and isomer selectivity


RILIS ionization schemesCurrently available elements

Elements for which ionization schemes have been tested to some extent but not yet applied

Elements for which ionization is feasible at RILIS but has not been tested

http://isolde.web.cern.ch/ISOLDE/


ISOL@MYRRHA: production yields


ISOL@MYRRHA: production yields

~Energy independent

Strong energy dependency

Strong energy dependency

p + 238U


ISOLDE-PSB

EURISOL

ISOLDE-SC and ISOL@MYRRHA

Prospects of ISOL@MYRRHA

• Can deliver:• pure RIB: selective ionization, chemistry, M/DM > 10.000• intense RIB x100 compared to the present ISOLDE (‘standard’ RIB)• RIB of good ion optical quality• optimal experimental conditions/lay-out/support• very long beam times

• Based on proven technology (largely on ISOLDE and TRIUMF experience)

• Long beam times (e.g. several weeks) for experiments that:• need very high statistics• involve many time consuming systematic measurements• hunt for very rare events• have an inherent limited detection efficiency

• Research in the field of fundamental interaction studies, nuclear physics, atomic physics, condensed matter research, life science,…

• Long term options:• 1-GeV proton beam (spallation and target fragmentation region)• post-acceleration of the RIB to 10 MeV/u


Complementary to other ISOL and In-Flight facilities

Nuclear Physics

Astro-physics

Atomic Physics

Fundamental Interactions

Other Applications

Decay: 1%

Reactions: 10%

Day Week Month YearTime scale

Reactions: 10%, 100 mb

Masses

Condensed Matter

Pilot studies

Prototypes

m, Q, <r2>

Prototype

Radiopharmacy (prototype)

Radiotherapy (prototype)

SHE chemistry

Rare decays, high precision: cluster decay, SHE

Systematic sample measurements

Bohr-Weisskopf, isotope dependence

(84<Z<92)

Correlation measurements, EDM

Production

Exploitation

HIE-ISOLDE, GANIL, TRIUMF, ORNL, EURISOL, GSI, RIKEN, MSU,…

ISOL@MYRRHA

Radiative capture reactions (low cross section)


Fundamental interactions

1. Nuclei at or close to the N = Z line - Nuclei with 0+ 0+ transitions - T = 1/2 mirror nuclei (e.g. 21Na21Ne)

2. Nuclei with fast (small logft) and pure G-T transitions

3. Neutral atoms with high atomic number Z - Atomic states with opposite parity close in energy - Strong nuclear octupole deformation - Simple atomic structure (e.g., alkali elements)

Possible subjects:

1. Ft0+ 0+

- Conserved vector current hypothesis - Unitarity of CKM quark mixing matrix - Right-handed currents - Scalar currents

2. Correlation measurements - Scalar currents - Tensor currents - Parity violation - Time reversal invariance

3. Superallowed beta transitions of the T=1/2 mirror nuclei

- Unitarity of CKM quark mixing matrix - Right-handed currents - Time reversal invariance - Scalar currents - Tensor currents

4. Symmetry tests in neutral atoms - Parity violation - Time reversal invariance

High-precision experiments with long beam times

• Data taking (statistics)• Instrument calibration (systematic

errors)

Nuclei of interest:

Type of experiments:


0+→0+ Fermi transitions

21 1 3074.4(12)

2 1R NS C V

V R

KFt ft s

G

1. CVC hypothesis

2. Unitarity CKM matrix

3. Right-handed currents

4. Scalar currents

J.C. Hardy and I.S. Towner, Phys. Rev. C 79 (2009) 055502

1. CVC OK up to 4 * 10-4 level

2 2 2 2 0.99995(61)ui ud us ubi

V V V V2.

1

2

2122

cos sin

sin cos

L R

L R

W W W

W W W

m

m

0.00003(30)

3.

2 1 2uii

V

'

0.0021 Re 0.0065S S

V

C C

C

4. Via inclusion of Fierz interference term:

(90% CL)


0+→0+ Fermi transitions: Error budget

Options: - improve quantities indicated by green & blue arrows (alkalis and noble gases only) - if CVC accepted Ft-measurements test dc - dNS from theoretical models - go for factor ~10 higher precision in Ft than available now for the 4 isotopes

indicated - investigate other candidates using a laser-ion source

• Overall precision: 4 * 10-4

Required precision of single measurements: < 10-3

T1/2 and BR : < 10-3

Theoretical corrections dC, dR ~ 1% : < 10%

Error budget and opportunities for ISOL@MYRRHA


Correlation measurementsTraps

• Search for exotic currents: pure Fermi (S current) or GT (T current) decayaF, aGT (nucleus recoil: trap, g-ray Doppler shift with crystal spectrometer) ; AGT (dominated by syst. errors)

• Symmetry tests: Parity violation and time reversal invariance AGT, BGT (parity) ; D (V and A), R (S and T) (time reversal, only n, 8Li and 19Ne measured)

Solution


Super-allowed decays of T=1/2 mirror transitions

2

0 21 6173(22)

1a

Vv V R

f KFt Ft s

f GO. Naviliat-Cuncic and N. Severijns, PRL 102 (2009) 142302 ; N. Severijns et al., PRC 78 (2008) 055501

A GT

V F

C M

C M

19Ne21Na

29P

35Ar 37K

1. CVC OK up to 3.6 * 10-3 level

defined from a(r), A(r), or B(r)

0.9719(17)udV2.More sensitive than 0+ → 0+ decays.

For 35Ar, e.g.: measuring A at 0.5% (now at 5%), gives Vud at 7 * 10-4.

r: from measured Ft and using Ft0+→0+

3. Scalar and tensor currentsa(r), A(r), B(r)

A.

B.

4. Parity violationA(r), B(r)

5. Time reversal invarianceR(r)

D. Pauwels Scientific Meeting January 6, 2010 Leuven

Nuclear Structureb-decay spectroscopy:

Interest in small b-decay branches:• Decay rate l ~ f x |M|2

branching ratio = l/ltot

• Beta-decay f-factor ~ (Q-E)5

transitions with large strength to high E

• Allowed / first forbidden / …

Required equipment:• Implant in catcher foil / detector – trap• Detectors for b, g, charged particles, n

Sn

Qb

b

n

Z,N

Z+1,N-1

Z+1,N-2

High-precision measurements and/or experiments with inherent limited detection efficiency:

• Example: g-ray crystal spectrometer with a bent-crystal geometry (cf. GAMS5): <10-5


Possible subjects for nuclear structure

2. Decay of ‘Halo’ nuclei– Decay into continuum– Clustering

– β n/p emission: study of p/ competition

– β 2p: only data for 31Ar

– β 2n: very limited information 11Li, 19C, 30-34Na, 52K

– β d/t emission: 6He (,d); 8He (,t)– New branches

• 8He (,d); 11Li (,pn)• βt 29,30,32Ne, 32,33,34Na; βd 32Ne, 34Na

1. (Multi-)particle emission

3. Other cluster studies– 12C – 3 α’s: decay of 12N/B

– 13N/C – add nucleon: decay of 13O/B

– 16O – 4 α’s / 12C+α: decay of 16N


Solid-state physics (8Li b-NMR)8Li b-NMR at TRIUMF• produce polarized 8Li

– circularly polarized laser light– asymmetry in -decay of 8Li

• Implant 8Li in surface– destroy asymmetry by sending in NMR

signal• Frequency and line shape tells about

interaction between solid and 8Li

What happens near an interface?• We go from 3D to 2D system• Changes in magnetic, electronic and structural properties with superior depth sensitivity.Questions:How/why do the properties change?On what scale ? Motivation: Better understanding of both bulk and interface Application in devices.


Solid-state physics (Emission Channeling)

Direct information on the lattice site of impurity atoms with high sensitivity and precision:

Understand the effect of impurity atoms and the influence of lattice defects

Understand electrical, magnetic, and optical properties

Elements for which channeling experiments have been reported

Important criteria: Decay T1/2 (< ~ months),

energy of emitted particle,

superposition decay chains,

radiation protection issues,

RIB yield.

Higher yield: more suitable isotopes and several new probe elements become available

Long and frequent beam access: more detailed systematic studies become possible


Atomic-physics techniquesObservables:

Mass,

Isotope shift,

Magnetic-dipole interaction parameter (A),

Electric-quadrupole interaction parameter (B),

Hyperfine anomaly

Nuclear binding energy,

Mean-square charge radius,

Magnetic-dipole moment (A),

Electric-quadrupole moment (B),

Mean-square neutron radius

Nuclear ground-state properties:

Model-independent information

Interest in laser- and radiofrequency-spectroscopy with:• High sensitivity (study of weakly-produced beams)

• Resonance-ionization spectroscopy• experiments with MOTs• Laser-Ion Source Trap (LIST) for ultra-high selectivity

• High precision (observing weak effects)• Collinear spectroscopy• experiments with MOTs• experiments with EBIT (highly-charged ions) and Penning traps


Collinear spectroscopy of Be(W. Nörtershäuser et al., PRL 102 (2009) 062503)

Opportunities with laser spectroscopyCharge radii of light nuclei

6He in MOT (L.-B. Wang et al., PRL 93 (2004) 142501)

Single-atom sensitivity

Hyperfine anomaly

Except for a few cases, there are no systematic measurements

Polarized beams

For fundamental-interaction studies, solid-state physics (see above), and biophysics (e.g., b-NMR of Cu atoms in proteins).

Ultra-selective ion source

LISTK. Blaum et al., NIM B 204 (2003) 331


Radio-pharmaceuticalsConventional cancer treatments:• Surgery• Radiation therapy• Combination of radiation and

surgery• Chemotherapy

149Tb produced at ISOL facility

Beginning of:• Systematic radio-nuclide therapy

Tumor-seeking tracer labeled with a emitter

Range of a emitters: 30-80 mm (cell surgery)

Important criteria:• Half-life• Radio-toxicity of daughter isotopes• Bio-kinetics (in-vivo stability of tumor-

seeking tracer)• Affordable production price• Reliable supply

Burkitt-lymphoma cancer study on mice:(G.J. Beyer et al., Eur. J. Nucl. Med. Mol. Imaging 31 (2004) 547)

Tumor-seeking tracer: Rituximab

Radio-isotope: 149Tb

5MBq 149Tb-MoAb, 5mg MoAb

300mg MoAb

5mg MoAb

No therapy

70-kg patient sample (5 GBq):

0.6-GeV p + Ta: ~1.5h/sample (~6000 per year)

1-GeV p + Ta: ~0.6h/sample (~15000 per year)


Timeline ISOL@MYRRHA


2020-2022: MYRRHA ADS commissioning phase → 1st beam on ISOL@MYRRHA possible

2013: finish concept design of ISOL system and target stations

2015: finish the engineering design

2016: awarding construction contracts

2017-2018: construction

2019: assembly and installation of ISOL and target system

2020: 1st beam on ISOL@MYRRHA

More information

iks32.fys.kuleuven.be/wiki/brix/index.php/Main_Page


ConclusionsISOL@MYRRHA provides intense and pure Radioactive Ion Beams (RIB) for experiments needing long beam times and/or frequent beam access.

ISOL@MYRRHA is complementary to other existing and future RIB facilities in various research fields.

A preliminary report addressing the technical and scientific aspects of ISOL@MYRRHA is being distributed amongst the NuPECC working groups and is available on-line.

Further applications for the full 4-mA beam?

Initial funding of the MYRRHA project granted (up to the end of 2014), BUT excluding ISOL@MYRRHA…


3 months

1 month

3

1

3

3

On-line

MaintenanceMYRRHA cycle:

Solid-state physics (8Li b-NMR)

D. Pauwels Scientific Meeting January 6, 2010 Leuven

Understanding physics of nanostructured materials:Microscopic information about local electric and magnetic fields

Experimental methods for studying magnetic depth profile:

Method Advantages Disadvantages

Polarized neutron reflectivity

Nanometer resolution Deterioration with surface roughnessRelatively low neutron flux at present neutron facilities

Synchrotron-based nuclear resonant scattering

Nanometer resolution Limited number of suitable Mossbauer isotopesSevere constraints for monochromator

Synchrotron-based resonant X-ray scattering

Nanometer resolution Absorption edge must be accessible for monochromator

Muon spin rotation Large penetration depth (~mm)

Significant beam-intensity losses at low E

8Li b-NMR Superior depth sensitivity

Only available at TRIUMF

ISOL@MYRRHA

Documents

Transcript of ISOL@MYRRHA