Nuclear astrophysical reactions by unstable beams and Progress of BRIF and BRIFII 不稳定核束核天体物理反应 北京放射性核束装置的进展 Wei-ping Liu 柳卫平 China Institute of Atomic Energy, CIAE 中国原子能科学研究院 6 th China Japan Joint Nuclear Physics Symposium 第六届中日核物理会议 May 16-20, 2006 Shanghai 上海

Study of some key nuclear astrophysical reactions by unstable nuclear beams

Interplay between astrophysics and nuclear physics Nuclear process –Main energy of star to balance gravitational collapse –Mechanism of isotope synthesis apart from Hydrogen –Rule the evolution process from the first few minutes after big bang to just before the end of star life Nuclear astrophysics –Using nuclear physics to explain the energy production and element synthesis in star and cosmos Exp The Nucl. Data Astro. Obs. Astro. Model ExpThe Abundance Dist.

Nuclear astrophysics and physics of unstable nuclei primordial and super novae high temperature and density environment, large amount of unstable nuclear involved into nuclear burning RIKEN RIBF proposal

Nuclear astrophysics ‘Lab’ B. Pfeiffer, et al., Z. Physik A357, 253 (1997)

Reaction network Cross section Decay half-life  

Challenge to experiment 11 C(p,  ) 12 N Gamow window Extremely low energy Vanishing low cross section

Our solution: indirect method RIB production W.P. Liu, NIM B204(2003)62 (d,n) or (d,p) measurement ANC or Spec factor Astrophysical reaction rates W.P. Liu, PRL77(1996)611

Direct capture process of 11 C(p,  ) N. C. Shu,…, W. P. Liu et al., Nucl. Phys. A 758 (2005) 419c Key reaction in hot pp chain Dominated by direct capture W. P. Liu et al., NPA728(2003)275

First measurement of primordial 8 Li(n,  ) 9 Li reaction rate Destroy reaction of 8Li: 8 Li(n,  ) 9 Li, 8 Li(d,p) 9 Li in inhomogeneous big bang ， APJ429(1994)499 Half-life of 8 Li: 0.83 s ， direct (n,  ) exp. impossible Z. H. Li, W.P. Liu et al. ， PRC 71, (R) (2005)

Comment on our results The paper presents excellent experimental work and removes a longstanding debate about the absolute cross section of 8 Li(n,  ) As far as I know, so far, no results have been published to determine a neutron capture rate of astrophysical importance

13 N(d,n) 14 O  13 N(p,  ) 14 O PRC, submitted

Summary of reaction studied 9C9C 12 N 18 Ne 17 F 14 O

Opportunities from BRIF and BRIF II BRIF: Beijing Radioactive Ion Facility

Physics : why BRIF Intensity , energy 100 keV-10 MeV/u, RIA proposal

The current Tandem lab Beam type, only stable, no noble gas Energy range, less than 14 MeV/q Instrumentation, no RMS, no ISOL Beam time: 100 % overdue

BRIF 100 MeV 200  A compact proton cyclotron mass resolution ISOL, 2 MeV/q super- conducting LINAC

BRIF energy and mass resolution

BRIF research opportunities and combinations 100 MeV, 200  A Proton Cyclotron ISOL Mass Resolution RIB Stable Beam Ion Source Super Conducting LINAC Tandem Accelerator 15 MV Neutron data Radiation physics Decay data Material physics Nuclear data Radiation physics Nuclear structure Reaction Astrophysics Atomic Physics Applications Radiation physics Nuclear structure Reaction Astrophysics Atomic Physics Tandem with unstable beam, proton- rich, fission heavy ion beam with higher beam energy, 20 MeV/q 100 MeV proton and neutron beams available by the year MeV neutron ISOL current terminals limitation of instrument and machine time

More n-rich beam: CARRISOL Horizontal tube He-jet + ISOL Neutron flux 1X10 14 /cm 2 /s Available in 2007 NuclideISOL (pps) I-1353×10 6 Xe-1389×10 7 Cs-1389×10 7 Xe ×10 8 Cs ×10 8 Cs ×10 8

Low  RFQ for new injector 17 MeV/q super-conducting LINAC RMS Large acceptance spectrometer Decay measurements

Beam energy

RFQ/DTL Low energy normal temp RFQ+ finger type DTL, multi charge heavy ion beam up to the energy accepted by SC LINAC 36MHz

SC LINAC Energy gain 17 MeV/q 36 ¼ wave length QWR L LHe tank QWR LHe tank

Large acceptance spectrometer Large D Q + detectors Mass range ， energy 5-10 MeV/u Solid angle 80 mSr ， P acceptance 10 ％ Mass resolution 300 via TOF and tracking

RMS Dipole Target chamber Electro Deflector Detector chamber Quadruples Beam diagnostics Beam diagnostics 12 m Electro Deflector Quadruples

Gamma array 10X BGO+seg. HPGe Eff MeV resolution 6 keV

Research opportunities Systematic study of shell evolution Nuclear astrophysics Mechanism of SHE Properties of medium mass neutron rich nuclei New decay modes Gamma array Recoil mass separator Large acceptance spectrometer Decay setup

Conclusion BRIF and BRIFII will open up exciting research opportunities With BRIFII: –new experimental terminals –higher beam energy of 35 MeV/q –100 % more beam time by separate operation –Limit: overall instrumentation usage –Available by the year of 2013 Chances are still open, and we welcome contributions, suggestions and new proposals We would like to collaborate with major domestic and foreign research groups and world labs to take their full research potential and to do cooperative jobs Call for user communities to build machine and detector and physics task force with more flexible way A nice play ground in Beijing to connect locations