Equipment

1. Equipment I-Yang Lee, Dave Morrissey, Robert Varner, and Carl Gross

2. 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.

3. 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

4. New equipment indentified • SOLITAIRE : gas-filled solenoid • HELIOS: solenoid • Radioactive target • CERDA : decay gamma-ray array • Target making capabilities

5. Beam requirement • Efficient beam pulsing : TOF for VANDLE, Hercules, etc.

6. Ionization schemes available (34 elements) (demonstrated at Mainz University, TIRUMF, HRIBF, JYFL) Ionization possible (theory) The most important piece of equipment- Radioactive Ion Beams with the HDU Upgrade Co/Ni rejection ratio = 10,000 Laser ion source results at HRIBF

7. In-beam spectroscopy

8. GRETINA at the HRIBF 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 Radford, Physics with GRETINA, APS/JPS Hawaii 2009

9. Hercules

10. UT / Kraków Isomer-scope for experiments with RIBs M. Rajabali, this session CARDS: • 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 g(-g) isomeric decay events in 10-1000 ns range Double MCP: Top MCP PLFs at 10-30 deg. Box Scattered beam to beam-dump Scattered beam to beam-dump Magnet Beam Target Foil with a circular hole Bottom MCP W. Królas, IFJ PAN Kraków HRIBF Users Workshop, November 13-14, 2009

11. BaF2 Upgrade BaF2 @ HRIBF • Giant Dipole Resonances • Properties of GDR as a function of nuclear temperature • Strength distribution in exotic nuclei • Isospin mixing • Coulomb excitation • 132Sn, 134Sn, 82Ge BaF2 @ ATLAS • 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 • Replace aging photomultipliers (PMT) • Last PMT replacement in 2002 • Replace 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)

12. 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 Experiments can be done now with 105 ions/s & 1017 deuterons or 1022 beam-target nuclei Estimated target thickness for Sn isotopes

13. Reaction studies

14. 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 PCN σER = σCN x Wsurvival Fission barrier lower than expected

15. ORRUBA Beamline • 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 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)

16. Oak Ridge Rutgers University Barrel Array (ORRUBA) • ORRUBA gives ~80% f coverage over the range 47° →132° • 2 rings – q < 90°: 12 telescopes (1000mm R + 65mm NR) • – q > 90°: 12 detectors (500mm R) • 324 channels total (288 front side, 36 back side) • HI beam • Deuterated plastic targets (C,C) (d,d) (d,p) (p,p)

17. Versatile Array of Neutron Detectors at Low Energy VANDLE (d,n) or decay experiments • 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 165 keV Can be arranged about 1 meter around target position, closer for small bars. Nov 13-14, 2009 HRIBF Workshop 1

18. Decay Studies

19. Beta-delayed neutron detector 3Hen GT FF • Nuclear structure • First detection of extremely neutron-rich nuclei • Isotopic abundances during r-process freeze-out • Nuclear reactor operation - β-delayed neutrons , isotopic abundances Competition between first-forbidden (FF) and Gamow-Teller (GT) transitions is observed through half-life and β-delayed neutron probabilities • 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 19

20. ARRA funded ORNL Modular Total Absorption Spectrometer MTAS total γ-efficiency photo-peak efficiency ~ 19 blocks hex shape, 20” long NaI(Tl) beta-strength function → nuclear structure “decay heat” → nuclear reactors applications

21. ARRA funded Oak Ridge Isomer Separator and Spectrometer (ORISS) Tandem and OLTF → C70 and IRIS-2 50 pnA protons Multi-pass Time of Flight separation for decay studies OLTF ΔM/M ~ 1: 400,000 !! efficiency ~ 50%

22. 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

23. Nuclear Astrophysics

24. 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 18Ne(α,p)21Na 21Na(p,γ)22Mg 22Mg(α,p)25Al 25Al(p,γ)26Si 26Si(α,p)29P 29P(p,γ)30S 30S(α,p)33Cl 33Cl(p,γ)34Ar 34Ar(α,p)37K 37K(p,γ)38Ca Compressor Gas purifier Concrete slab Roots blower Turbo pump Gas nozzles and chambers X-ray burst (α,p) and (p,γ) reactions for element synthesis

25. Application

26. 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

27. 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

28. 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.