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JINR SCIENTIFIC COUNCIL 102 nd Session, 27-28 September 2007, Dubna. ACTIVITY for the DRIBs PROJECT. S.N. DMITRIEV Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research. U400M CYCLOTRON. DRIBs Transport Gallery. U 400 CYCLOTRON. DRIBs Project.
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JINR SCIENTIFIC COUNCIL 102nd Session, 27-28 September 2007, Dubna ACTIVITY for the DRIBs PROJECT S.N. DMITRIEV Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research
DRIB’s complex equipment • Power supply for magnet – 165 units • ECR-source - 2 • Vacuum pumps - 49 • Beam current diagnostics – 35 • Diagnostic station for RIB – 9 • RF systems – 9
DRIBs from 2004 to 2006 • 2004 year Run • 2006 year Run
Program of modernization of the FLNR cyclotron complex • 1. U400M • 2. U400 – U400R. • 3. MT25
Modernization of the U400M cyclotron • to increase the light ion beams intensity by the factor of 4 – 5 for producing of secondary beams, • to improve the quality of beams, • to increase the maximal energy of accelerated ions up to 100 MeV/A, • to improve the radiation safety conditions, • to accelerate “low” (6÷15 MeV/A) energy ions (move some experiments from U400 to U400M), • to extract the beams to the second direction.
February – September 2007 • new axial injection line; • new “warm” ECR ion source (DECRIS-2); • new magnetic structure of the central region of U400MR; • second beam extraction system; • new producing target for secondary beams; • new local radiation shielding; • superconducting 18-GHz primary beam ion source DECRIS-SC2 (under testing); • “warm” 14-GHz secondary beam ion source (under testing).
Total modernization of the target unit • Development design of the disposable, nonseparable, quick-detachable, target block. • 6He output diagnostics from the catcher. • Creation of effective neutron traps around the target. • Ajustment of the new 14 GHz ion source. • Generation and acceleration of the He8.
Fusion, transfer and breakup reaction mechanisms induced by halo nucleus 6He JINR (Dubna), CSNSM (Orsay), IRS (Strasbourg), ULB (Bruxelles), Vanderbilt Univ. (USA) 166Er(6He,6n)166Yb &165Ho(6Li,5n)166Yb <==> 166Er(4He,4n)166Yb//PRC48(1993)319// 3 2 1 6He + 166Er 172Yb* 166Yb + 6n 6He + 166Er 170Yb* + 2n 6He + 166Er 168Er* + 4He DRIBs Nov.-Dec.’07 Chan.2 U400
Deep sub-barrier fusion of 6He + 206Pb For E < 20 MeV (2n channel)MSP-144 (focal plane) SETUP FOR ACTIVATION MEASUREMENTS with MSP-144 dE/dx~40keV/mm target~20mm E ~ 0.4MeV E~2.5MeV astrophysics, nucleosynthesis
U400 U400R • Beam intensity of masses A ≈ 50 and • energy ≈ 6 MeV/n up to 3 ρμa. • Ion energy variation on the target with factor 5. • Energy spread on the target up to 10-3. • Beam emittance on the target – 10 π mm · mrad. • Cyclotron average magnetic field level • from 0,8 up to 1,8 T. • New equipment.
U400 U400R Plan of modernization
JINR SCIENTIFIC COUNCIL 102nd Session, 27-28 September 2007, Dubna ACTIVITY for the DRIBs PROJECT S.N. DMITRIEV Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research THANKS FOR YOUR ATTENTION
Estimated results and experimental method Immediate object proposed for the primary experiments is the study of complete fusion and breakup reaction of 6He halo nuclei taking place in the interactions with medium mass targets at the energy range E=5-10 MeV/nucleun. The experiment is aimed at the following tasks: 1. In a range of Elab=55-62 MeV the cross section will be measured for the 166Er(6He,6n)166Yb reaction. Data on 5n evaporation will be also obtained. Reaction products resulting from the 6He breakups will be observed too. 2. Population probabilities will be measured for the levels of the ground-state rotational band in 166Yb. These data will be compared with calculations treating both the neutron evaporation cascade and the multiple emission of g rays at the stage of the nucleus descent along the yrast line. The search of a peculiarity in the values of orbital momentum allowed for the compound nucleus formation should be possible. It will interesting to know if there are orbital momentum going beyond the typical lcrit values peculiar to non-halo nuclei. 3. In the case of the breakup reactions 6He+166Er=>170Yb*+2n and 6He+166Er=>168Er*+a energy sharing among the breakup cluster (2n or a) and recoil nucleus will be estimated from the measured yields of the evaporation residues and the energy spectra En and Ea. 4. Additionally,6Li+165Ho and 6Li+166Er reactions will be studied at quite similar projectile energies 50-57 MeV. In the 1st case the same evaporation residue 166Yb populated in 5n channel will be investigated and in the 2nd the products of the 6Li breakup ending with the capture of its a cluster by 166Er will be studied. Beam time estimation: 4 weeks per 6He and 1 week per 6Li.