Equipment I-Yang Lee, Dave Morrissey, Robert Varner, and Carl Gross.
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Transcript of Equipment I-Yang Lee, Dave Morrissey, Robert Varner, and Carl Gross.
Equipment
I-Yang Lee, Dave Morrissey, Robert Varner, and Carl Gross
Conclusions• Enough equipment in place to make good
use of the new science opportunities of the C70 cyclotron upgrade.
• A number of new equipment are under construction or being planned to be used at HRIBF.
• A few new equipment has been identified.
• Efficient beam pulsing is needed.
New equipment under construction
• 3Hen - neutron detector
• MTAS - total absorption spectrometer
• ORISS - isomer mass spectrometer
• S-ORRUBA – Si detector array
• Fusion-fission detector
• VANDLE – neutron spectrometer
• BaF2 upgrade – gamma-ray array
• S-Hercules – recoil detector
• GRETINA – gamma-ray tracking array
New equipment indentified
• SOLITAIRE : gas-filled solenoid
• HELIOS: solenoid
• Radioactive target
• CERDA : decay gamma-ray array
• Target making capabilities
Beam requirement
• Efficient beam pulsing : TOF for VANDLE, Hercules, etc.
Element Sn Ni Ge Cu Co Ga Mn Fe Al Ho Tb Dy Sr
Efficiency
Measured (%)
22 2.7 3.3 2.4 >20 9 0.9 40
Ionization schemes available (34 elements) (demonstrated at Mainz University, TIRUMF, HRIBF, JYFL)
Ionization possible (theory)
1H
2He
3Li
4Be
5B
6C
7N
8O
9F
10Ne
11Na
12Mg
13Al
14Si
15P
16S
17Cl
18Ar
19K
20Ca
21Sc
22Ti
23V
24Cr
25Mn
26Fe
27Co
28Ni
29Cu
30Zn
31Ga
32Ge
33As
34Se
35Br
36Kr
37Rb
38Sr
39Y
40Zr
41Nb
42Mo
43Tc
44Ru
45Rh
46Pd
47Ag
48Cd
49In
50Sn
51Sb
52Te
53I
54Xe
55Cs
56Ba
* 72Hf
73Ta
74W
75Re
76Os
77Ir
78Pt
79Au
80Hg
81Tl
82Pb
83Bi
84Po
85At
86Rn
87Fr
88Ra
** 104Rf
105Db
106Sg
107Bh
108Hs
109Mt
110Ds
111Rg
112Cn
113Uut
114Uuq
115Uup
116Uuh
117Uus
118Uuo
* 57La
58Ce
59Pr
60Nd
61Pm
62Sm
63Eu
64Gd
65Tb
66Dy
67Ho
68Er
69Tm
70Yb
71Lu
** 89Ac
90Th
91Pa
92U
93Np
94Pu
95Am
96Cm
97Bk
98Cf
99Es
100Fm
101Md
102No
103Lr
The most important piece of equipment- Radioactive Ion Beams with the HDU Upgrade
Laser ion source results at HRIBF
Co/Ni rejection ratio
= 10,000
In-beam spectroscopy
Equipment Topics existing new
Transfer reaction CLARION, Hyball GRETINA Coulomb excitation CLARION, Hyball GRETINA Coulomb excitation BaF2 PMT, electronics Unsafe Coulex, DI GRETINA High spin CLARION, Hyball, RMS GRETINA Isomer from DI CARDS, dual MCP Heavy nuclcei HERCULES SuperHercules, GRETINA g-factor RIV, RIF
CLARION, Hyball, Gammasphere
13 October 2009 Radford, Physics with GRETINA, APS/JPS Hawaii 2009
Plan to host GRETINA starting summer/fall 2012• Following first experimental campaign at MSU/NSCL Jan – Jun
2012?• Six-month campaign, focus of nuclear structure with neutron-
rich RIBs• Intend to enhance the HRIBF PAC with GRETINA-physics experts• Expect that, due to exciting physics reach, ~ 80% of the 6-
month campaign could be devoted to GRETINA experiments• Future GRETINA@HRIBF campaigns expected, but timescale
TBD• Locate at RMS target• Electronics & CPUs on
mezzanine above beam line• Est. site prep cost ~$450k
budgeted for FY10-11• Need to identify required
auxiliary detectors
GRETINA at the HRIBF
Hercules
Top MCP
Botom MCP
Foil witha circular hole
MagnetBox
Target
CloverGe
CloverGe
Scattered beamto beam-dumpBeam
PLFs at~10-30 deg.
W. Królas, IFJ PAN Kraków HRIBF Users Workshop, November 13-14, 2009
UT / Kraków Isomer-scope for experiments with RIBs
• radioactive beams of A ≈ 80 on 124Sn or 130Te target (~2 mg/cm2)
• MCP tagging on PLFs emitted at and around the grazing angle, 10-30 deg. – MCP efficiency ≥ 90%
• scattered beam ions produce no signal
• CARDS: 4 Clover Ge detectors in a close geometry to measure time stamped (-) isomeric decay events in 10-1000 ns range
M. Rajabali, this session
Top MCP
Bottom MCP
Target
Beam
BoxMagnet
PLFs at10-30 deg.
Scattered beamto beam-dump
Foil with a circular hole
Scattered beamto beam-dump
Double MCP:
CARDS:
BaF2 Upgrade
Replace aging photomultipliers (PMT)•Last PMT replacement in 2002Replace current CAMAC/FASTBUS electronics•Option 1 - Modern VME ADCs and TDCs •Simple replacement does not extend capabilities•Option 2- Digital electronics •Individual gates, “dual” gain, reduced module count, added capability for particle ID and timing (100 ps goal)
Giant Dipole Resonances •Properties of GDR as a function of nuclear temperature•Strength distribution in exotic nuclei•Isospin mixingCoulomb excitation •132Sn, 134Sn, 82Ge
Characteristics •Merged smaller arrays from ORNL (76), TAMU (56), and MSU (21)•~150 detectors arranged in a single wall, 37-packs, 19-packs•0.5-100 MeV photon energy detection•Fast/slow light comparison for pile-up and n-γ discrimination•Timing resolution on order of 200 ps
BaF2 @ MSU
BaF2 @ ATLAS
BaF2 @ HRIBF
Implanted radioactive targets for light ion spectroscopy •Build a beam line from RIB injector to the target position of the Enge•Implant beams into thin carbon foils (20 μg/cm2) at the target position of the Enge•Our proposed radioactive targets will be equivalent to 0.001 - 1 μg/cm2 in the 4 mm2 beam spot•Simultaneously bombard the implantation area with light ion beam from the tandem (no handling until
post-exp)•Measure transfer products with Enge at forward angles (<20°) and with silicon (20°-60°)•Goal is 1022 target-beam nuclei (1011 i/s x N ~ 1022 ~ 105 i/s x 1017 (CD2 100 μg/cm2)•Zr targets can be made by implanting more volatile Kr, Rb, and Sr beams•Upgrade yields over 170 isotopes with suitable intensity and half-lives to reach 1011 target nuclei
A Z N T1/2 (s) Yield (i/s) Atoms/4-mm2 * Eff. thick. (μg/cm2)*
121 50 719.74E+0
43.51E+09 3.03E+14 1.52E+00
123 50 731.12E+0
72.23E+10 1.93E+15 9.84E+00
125 50 758.33E+0
56.10E+10 5.27E+15 2.73E+01
126 50 763.16E+1
27.34E+10 6.34E+15 3.32E+01
127 50 777.56E+0
37.13E+10 8.62E+14 4.55E+00
128 50 783.54E+0
35.59E+10 3.17E+14 1.68E+00
129 50 791.34E+0
23.15E+10 6.75E+12 3.62E-02
130 50 802.23E+0
21.42E+10 5.07E+12 2.73E-02
131 50 815.60E+0
16.15E+09 5.51E+11 3.00E-03
132 50 823.97E+0
12.80E+09 1.78E+11 9.74E-04
Estimated target thickness for Sn isotopes
Experiments can be done nowwith 105 ions/s & 1017 deuterons
or 1022 beam-target nuclei
Reaction studies
Equipment Topics existing new
Fusion TOF-IC, gas-filled Enge
gas-filled spectrometer, neutron detectors, deflector, Wien fi lter, pulsed beams
Fusion SOLITAIRE : gas-filled solenoid QE, DI, fission Fusion-fission detector Transfer reaction ORRUBA S-ORRUBA Fusion, fusion-fission
Hercules, pulse beams
Neutron VANDLE, pulse beams Transfer reaction HELIOS, pulse beams
Fusion-fission detector•Detect and identify all binary reactions (fission, deep-inelastic, quasi-fission, scattering, etc) and if possible, evaporation residues
•Optimized for very exotic RIBs at low intensity (<50k ions/s) •Segmented-anode ionization chamber (IC) coupled with Si and CsI detectors
•IC dimensions (HxWxL) are 20 cm x 20 cm x 30 cm•Foil target located inside IC•Gas (CF4 ~ 40 Torr) of IC provides Z by energy loss•Si pixels and CsI (Anger Camera) provide energy and angular resolution (2°)
•Ion drift time and wires buried in anode structure provide additional position information
•Hit pattern and position suppresses beam-gas interactions•Isobar composition of beam from anodes upstream of target•Micro-channel plates provide time, triggers, beam counting, etc.•Expect 50% efficiency for binary reactions•Present system works mostly with inverse kinematic reactions and is sensitive to 1 mb cross-section for ERs; only 3-5% efficiency for fusion-fission and complicated by background
σCN = σcapture x PCNσER = σCN x WsurvivalFission barrier lower than
expected
ORRUBA Beamline
Oak Ridge Rutgers University Barrel Array (ORRUBA)•Transfer reactions such as inverse kinematics (d,p)•2 rings of 12 position sensitive ΔE-E telescopes (65 μm, 1000 μm)•Rings centered at 90° but can be repositioned•up to 432 channels of ASICs (Washington U. (St. Louis) electronics)
Beam line 35•Located next to the Enge Spectrograph•Intended to support ORRUBA and SIDAR, and perhaps the 1-meter scattering chamber•Partial funding from Center of Excellence for RIB Studies for Stewardship Science•Reduces demand on BL-21 which is a flexible beam line for general use and home to the large 1-m scattering chamber
Oak Ridge Rutgers University Oak Ridge Rutgers University
Barrel Array (ORRUBA)Barrel Array (ORRUBA)• ORRUBA gives ~80% coverage over the
range 47° →132°
• 2 rings – < 90°: 12 telescopes (1000m R + 65m NR)
– > 90°: 12 detectors (500m R)
• 324 channels total (288 front side, 36 back side)• HI beam
• Deuterated plastic targets
(d,p)
(p,p)
(d,d)
(C,C)
VANDLE (d,n) or decay experiments
Nov 13-14, 2009 HRIBF Workshop 1
165 keV
Versatile Array of Neutron Detectors at Low Energy
•2 size plastic scintillator bars•Small 60 x 3 x 3 cm bars for 150<En<2000 keV•Large 200 x 5 x 5 cm bars for 1<En<15 MeV
Efficiency measured at Ohio U. for one prototype small bar
Over 25% near 1 MeV
Can be arranged about 1 meter around target position, closer for small bars.
Topics Equipment existing new
Properties at Closed Shells CARDS CERDA(78-Ni, beyond 132-Sn) CLARION GRETINA/GRETA
P_n values 3Hen , Vandle
Beta-Strength, Total Decay Energy MTAS / ORISS
Conversion Electron Spec. Segmented Si(Li)
Recoil lifetimes Plunger / Silicon CD
General Isobar Separator ORISS
Speculative Recirculator Storage Ring
Decay Studies
19
Beta-delayed neutron detector 3Hen•Nuclear structure•First detection of extremely neutron-rich nuclei•Isotopic abundances during r-process freeze-out•Nuclear reactor operation - β-delayed neutrons , isotopic abundances
•3He tubes preamps, HDPE structure, HV, and power supplies in-house•Require electronics (Pixie-16) which will be used for all decay spectroscopy work •Beta detection system
FF
GT
Competition between first-forbidden (FF) and Gamow-Teller (GT) transitions is observed through half-life and β-delayed neutron probabilities
ARRA funded ORNL Modular Total Absorption Spectrometer MTAS
~ 19 blocks hex shape, 20” long NaI(Tl)
photo-peakefficiency
total -efficiency
beta-strength function → nuclear structure
“decay heat” → nuclear reactors applications
ARRA funded Oak Ridge Isomer Separator and Spectrometer (ORISS)Tandem and OLTF → C70 and IRIS-2
ΔM/M ~ 1: 400,000 !!efficiency ~ 50%
50 pnA protons Multi-pass Time of Flightseparation for decay studies
OLTF
Compact Efficient Recoil Decay Array
• Joint UT/MSU/ORNL/Rutgers proposal.
• Beta, alpha, and proton decay studies are possible at rates as low as 1 particle per day.
• Array contains– A central planar Ge detector;– 16 clover detectors close-packed
around the central planar Ge detector.
• Ions are implanted into the central Ge detector and correlated with subsequent decays in space and time.
• Clover detectors arranged in two rings of eight around a central Ge DSSD for particle gated gamma-ray spectroscopy.
• High gamma-ray efficiency– ~25% at 1300 keV.– 55% at 100 keV
Topics Equipment existing new
Direct Capture Reactions DRS
Decay Properties, P_n values CARDS 3Hen , Vandle of r-process nuclei, as far out as possible TOF mass values ~0.5 MeV ORISS
(d,n) reactions, e.g., 25-Al Vandle
(3-He,n) reactions 3He jet tgt, Vandle
Proton scattering Rxn’s LEDA/SIDAR/TUDA
Local Production of 7-Be, e.g. PossibleIsotope Production Facility
Nuclear Astrophysics
windowless gas cell to a gas jet target• Transfer reactions (3He,d), (3He,α), etc. on RIBs• Direct (α,p) cross-section measurements• Factor of 5 higher target densities (1019
atoms/cm2) • Localized target • (3He,d) populates single-particle states• (3He,p) and (3He,t) reactions• (3He,n) when coupled to VANDLE neutron
detector• (3He,α) reactions with n-rich beams e.g. 132Sn,
82Ge• (p,γ) with higher density targets• (d,p) with improved resolution
X-ray burst (α,p) and (p,γ) reactions for element synthesis
18Ne(α,p)21Na21Na(p,γ)22Mg22Mg(α,p)25Al25Al(p,γ)26Si26Si(α,p)29P29P(p,γ)30S30S(α,p)33Cl33Cl(p,γ)34Ar34Ar(α,p)37K37K(p,γ)38Ca Compressor
Gas purifierConcrete slabRoots blowerTurbo pumpGas nozzles and chambers
Application
Equipment Topics existing new
Surrogate reactions
Charge particle detectors Spin Spectrometer
C70 enhanced Applications
• Isotopes research– Little impact on the facility– Only beam time
• Surrogate reactions for applications– Charged particle detectors for reaction
product– Spin spectrometer useful to measure spin
distributions in compound system
Not enhanced by C70
• Tritium Beams– Charged particle detectors
• Normal and inverted kinematics• ORRUBA, ENGE spectrometer
– Tritium handling area• Preparation of sputter cones• Preparation of tritiated foils for targets• Use IRIS1 & 2 or new tritium injector line
• AMS– Detector is gas-filled Enge spectrometer, Bragg
counter• Artificial Joint Wear
– 7Be production
Conclusions• Enough equipment in place to make good
use of the new science opportunities of the C70 cyclotron upgrade.
• A number of new equipment are under construction or being planned to be used at HRIBF.
• A few new equipment has been identified.
• Efficient beam pulsing is needed.