Progress at other U.S. RNB facilities (Joint RIBF/FRIB Users Meeting, APS/JPS Meeting, Hawaii 2009) W. Nazarewicz HRIBF CARIBU at ATLAS Cyclotron Facility at TAMU RESOLUT at FSU TWINSOL at Notre Dame

Holifield Radioactive Ion Beam Facility - Floor plan Daresbury Recoil Separator (DRS) Time-of-Flight Spectrometer Scattering chamber 25 MV Tandem Electrostatic Accelerator Recoil Mass Spectrometer (RMS) On-Line Test Facility (OLTF) Oak Ridge Isochronous Cyclotron (ORIC) Enge Magnetic Spectrograph Injector for Radioactive Ion Species 1 (IRIS1) Injector for Stable Ion Species (ISIS) Second-stage Isobar Separator Low-energy Radioactive Ion Beam Spectroscopy Station (LeRIBSS) Example cyclotron at ARRONAX Facility, Nantes, France Proposed cyclotron room High Power Target Lab (HPTL) & Injector for Radioactive Ion Species 2 (IRIS2) Ti:Sapphire lasers at HRIBF IRIS2 undergoing commissioning now; HPTL operational since 2006 Enables use of laser photodetachment for beam purification. Suppress contamination by 99.9% with minimal loss of desired isotope [e.g. F(O),Cl(S),Ni(Co)] Enables use of resonance laser ion sources [Al,Mn,Fe,Co,Ni,Cu,Ga,Ge,Sn,Tb,Dy,Ho …] Rasterization of ORIC beam over up to 5cm diameter targets allows higher beam current ORIC beam at oblique incidence allows liquid and foil targets at higher beam current Second RIB production platform provides redundancy

HRIBF – recent science highlights Studied mirror levels with 26Al(d,p)27Al First measurement of the 26Al(p,p)26Al excitation function Proton spectrum: 185 ug/cm2 Target, 107 MeV 10Be beam LeRIBBS: The section of beta-gated gamma spectrum measured for 81Zn decay 10Be(d,p)11Be Productive despite the interruption in RIB delivery Commissioning Experiments at the Low-Energy Radioactive Ion Beam Spectroscopy Station (LeRIBSS) The section of beta-gated gamma spectrum measured for 81Zn decay. The 216-keV and 711-keV gamma transitions can only result from the decay of 81Ga produced as a daughter activity of 81Zn. The 81Ga ions, initially produced at a rate about five orders of magnitude higher than that of 81Zn, were practically removed from the separated positive-ion beam.

Beams and science with the cyclotron replacement Evolution of structure: Coulex, moment measurements, transfer at 132Sn & beyond Collective properties in extended neutron radii: Coulomb excitation near 96Kr Evolution of structure near 78Ni: Transfer reactions, Coulex, moment measurements Reaction mechanisms for the formation of superheavy nuclei Decay properties of nuclei at the limits: Crucial for understanding the formation of elements from iron to uranium Baseline Yields for a C70-based HRIBF Ge Sn • Basic Production method is direct 70 MeV proton induced fission on uranium carbide targets • Target geometries are disks 3 cm diameter by 1.1 cm thick or 5 cm x 1.1 cm (6g/cm3 UCx density) • Fission induced by secondary neutrons is included, and plays an important role. • Maximum beam currents are based conservatively on deposited power densities used in similar targets at HRIBF. The limit is taken to be 88 W/g. • Beam assumed to be “painted” almost uniformly across the UCx target face. • Corresponding maximum beam currents are 82 and 185 μA respectively for 3 cm and 5 cm. • A conservative limit of 80% of these limits is used in beam intensity calculations. • In future we expect to develop effective secondary neutron production targets that can withstand 750 μA proton beams for “cold fission” production of n-rich beams by U(n,f). I just noticed that I unintentionally left the baseline yield for the photofission driver (edu) on the plot as a thin green line. beam current 185 μA beam current 185 μA

HRIBF, Upgrade for the FRIB Era
An HRIBF Users Meeting
November 13-14, 2009 http://www.phy.ornl.gov/workshops/users09/ The HRIBF users group is proud to organize a workshop on the proposed high-current cyclotron upgrade to the HRIBF. The purpose of the workshop is to build the science case for the proposed new production driver based on a 70-MeV fixed-energy light-ion cyclotron. In addition, the HRIBF strategic plan will be updated based our discussions at the workshop. The workshop will begin at 8:30 am on Friday morning and continue through to approximately 9:30 pm. We will reconvene on Saturday at 9:00 am and expect the meeting to conclude around 1 pm.

CARIBU: Californium Rare Isotope Breeder Upgrade @ ATLAS CARIBU upgrade Fall 2009: 2 mCi source  tests & yields studies left part: floor plan of CARIBU and a picture of the on-going  assembly;         right part: intensities of sample nuclei in the low-energy  stopped beam) and re-accelerated beam areas as a function of the source strength. Note that we plan to build up to  the 1 Curie source in three steps. Winter 2009 – Spring 2010: 80 mCi source  1st expts. Summer 2010: 1 Ci source  Full research program

Proposed ATLAS efficiency and intensity upgrade Increase intensity of stable beams from ATLAS by factor >10 Increase intensity of CARIBU reaccelerated beams by > 5-10 Increase intensity of in-flight radioactive beams by >100 2 Booster + 2 ATLAS cryomodules Ion trap experiments 2 new bG=0.062 cryomodules, 12 cavities EBIS CARIBU the plan for the efficiency and energy upgrade of ATLAS.  The various elements of this effort are indicated. Recoil separator Energy Upgrade Cryomodule MHB RFQ MEBT (Chopper and Buncher) 2 PII cryomodules

First results from HELIOS U. Western Michigan, Manchester, ANL collaboration z Improved resolution for 11,12B(d,p)12,13B “Conventional” HELIOS Preliminary HELIOS Preliminary ~300 keV ~100 keV qCM=6o-29o qCM=16o-29o 11B(d,p)12B Latest experimental development: HELIOS is running. The data are from an experiment with a stable 11B beam and a radioactive 12B beam. The left and middle spectra compare results taken the conventional way (Si array) and with HELIOS and show the improvement in resolution. That is illustrated further on the right where two states separated by 200 keV in 13B are clearly visible. Alan Wuosmaa will discuss this further in his Hawaian talk. 12B(d,p)13B 3.48 MeV 3.68 MeV

Examples of reaccelerated beams produced in DIC: Projected Beam Intensities from LIG after K500 (p,n) Max. Energy Intensity Product MeV/A particles/s 27Si 57 6 x 103 50Mn 45 2 x 104 54Co 64Ga 4 x 104 92Tc 35 106In 28 108In 3 x 104 110In 26 6 x 104 We are within a year of our first accelerated RNBs from our K500 cyclotron at medium energies (up to about 50 MeV/A for lighter ions).  I have attached a layout of the facility following the upgrade and examples of beams.  First beams will come from accelerating H^- from the K150 cyclotron onto our light ion-guide target.  This is probably more than you want.  Also we have continued our program of producing in-flight beams with MARS over the last years.  Most recent work involves 23Al, 27P, and 31Cl beams.  We are implanting the beams into silicon detectors and measuring beta-delayed proton decay for states around the proton threshold.  This information is needed to get resonances for (p,gamma) reaction rates. The acronym that has been adopted for our new facitlity is T-REX (TAMU Reaccelerated Exotics) t1/2>100ms Assuming 14 mA beam, realistic LIG, CBECR, transport and K500 extraction efficiencies

RESOLUT: a new radioactive beam facility at FSU RF-Resonator Magnetic Spectrograph Target Position Solenoid 2 Solenoid 1 Mass selection slits Production target Experiment Proton-decay Q-value spectrum In-flight production, separation of radioactive beams Superconducting RF-beam cooling Driver accelerator: Tandem + SC Linac Primary beams: Mass 6-40 10-3 MeV/u RIB produced: 6He, 7Be, 17N, 18Ne, 25Al, 30P , 104-105 pps RIB possible: Almost all T=1/2, T=1 with 6<=A<=30 Counts/50 keV This resonance dominates astrophysical production of 26Alm 25Al - 24Mg (tof) P.N. Peplowski et al.: PRC 79, 032801R (2009): The lowest (l=0) 26Si -Resonance

TWINSOL – Notre Dame RNB Facility an interesting recent result concerning total reaction cross sections for "weakly bound" and "halo" nuclei.  The data for 8B+58Ni, 7Be+58Ni, 6Li+58Ni, 6He+209Bi, and 8Li+208Pbwere taken here at ND.  The other data sets are from the literature.  Observed was that the "reduced" cross section (total reaction cross section divided by the square of the system radius), when plotted against the reduced energy (cm energy divided by the Coulomb barrier) shows some striking regularities.  "Weakly-bound" systems such at the 6,7,8Li and 7,9Be isotopes follow a trajectory that is well separated from that of the "normal" system 16O+64Zn, presumably due to the effects of the weak binding. However, the halo systems (8B, 6He) follow yet another trajectory that shows even larger enhancement.