1. Progress of Experimental Nuclear Astrophysics Weiping Liu China Institute of Atomic Energy (CIAE) August 26-30, 2004, Beijing Beijing Summer School

2. Nuclear Astrophysics  Marco and Micro  Nuclear physics in energy production and element synthesis  Process, time scales, environment, abundance  Astrophysical model  Mass, cross section, half-life  Low energy and high isospin challenge

4. ®RIKEN proposal

5. Great discovery in 20 th century  3K microwave background radiation,1965, experimental support for Big-Bang theory  Detection of solar neutrino, 1960, message from solar interior  Element distribution anomaly in metal star  Detection of 26 Al  -ray, 1980, direct support of explosive nuclear synthesis, development of  -ray astronomy  Detection of SN1987A supernova explosion,1987

6. Table of contents  Nuclear astrophysics and experimental tools  Examples related to solar neutrino problem  More examples

7. Related knowledge in this school  RNB Production, Lewitowicz, Zhan  Nuclear astrophysics, Woods, Motobayashi  Nuclear structure, Otsuka, Wyss, Akaishi, Shimoda, Toki, Ye  More, Peitzmann, Akiba

8. How nuclear physics play role. ®RIA white paper 2001

9. Exp The Nuclear data Astro Obs Astro Model ExpThe The interplay between nuclear physics and astrophysics Abundance Estimation

10. H-burning Stellar process Inter stellar buring Primodual He-burning Si/Fe burning Gravational corapsse Supernovae Black Hole/neutron star Brief picture of element evolution

11. Maxwellan dist. e -E/kT Gamow peak Coulomb penetration e -bE^(1/2) Res. Peak Probability 温度（能量） kTE0E0 ErEr Extra low energies 11 C(p,  ) 12 N

12. The Astrophysical S – factor, Summerfield parameter

13. Important NP data  S-factor, focus on NP, down to astrophysics  Reaction rates, direct input to network calculation  Direct capture, direct reactions  Resonance, level scheme, level width, and partial width

14. Where is reaction and decay data in network calculation

15. Nuclear Astrophysics Experiments  Solar neutrino problem  40 Ti  -decay  7 Be(d,n) 8 B reaction  Other experiments

16. Sun Earth SN1987 Nuclear Reaction pp:p + p  2 H + e + + u e pep:p + e - + p  2 H + u e 7 Be: 7 Be + e -  7 Li + u e 8 B: 8 B  8 B * + e + + u e Detector (Homestake, Gallex, SNO Sage, Kamiokande, ICARUS) MSW Effect (  oscillation  e   x ) Solar Neutrino Neutrinos form Supernovae Where does neutrino come from?

17. pep 7 Be 8B8B Homestake Gallium Kamiokande 7 Be ICARUS pp Neutrino detection Radiochemical Homestake exp.  e + 37 Cl  37 Ar + e - Gallex and Sage  e + 71 Ga  71 Ge + e - Direct measurement Kamioka, SNO Exp.  + e   + e ICARUS Exp.  e + 40 Ar  40 K + e-  x + e-    + e-

18. Present: basically sensitive to  e Super Kamiokande Gallex, Sage Homestake SNO Future: Neutrino of all flavor Super Kamiokande ICARUS Underground Lab... Solar neutrino experiments

19. How nuclear physics connected with solar neutrino problem: example  Nuclear physics from production and detection of solar neutrino detection Solar neutrino problem Solar neutrino detector on earth Predictio n of solar model Detection efficiency Neutrino property Neutrino productio n cross section RNB experime nts 2-3 time diff 40 Ti  - decay 7 Be(d,n) 8 B reaction

20. Nuclear Astrophysics Experiments  Solar neutrino problem  7 Be(d,n) 8 B reaction  40 Ti  -decay  Other experiments

21. Two process: Absorption  e + 40 Ar  40 K * + e - 40 K *  40 K +   + e -   ’ + e - ’ M(e - ) = 2 Scattering  x + e -   x ’ + e - ’ M(e - ) = 1 ICARUS and neutrino oscillation ®ICARUS homepage

22. 40 K 39 Ar + p 40 Sc 40 Ar 40 Ti Isospin Mirror 4+4+ 0+0+ 4-4- 0+0+ 0+0+ 0+0+ 4.38 IAS 7.58 4.36 IAS -1.5 ++ +2 +1-2 TzTz ee 40 Ar + p 40 K + n 40 Sc + e + +  e 40 Ti 40 Ar +  e 40 K * Mirror symmetry in mass 40  40 Ti and 40 Ar Mirror symmetry

23. IAS (J , T 0 ) ++ (Z-3, N+1) +2p Two-Proton Daughter (Z-2, N+1) + p Proton Daughter Seq. 2p p (Z-1, N+1) Emitter Q EC SpSp (J , T 0 ) (Z, N) Precursor 2 He General  -decay scheme    F GT  -decay measurement

24. Some basics about  -decay 

25. Selection rules ClasslogftLFermi transitionGamow-Tellor transition II II Superall owed 2.9-3.700No(0), 1No Allowed< 5.900No(0), 1No 1 st forbidde n > 8.01(0), 1Yes0, 1, 2Yes 2 nd forbidde n > 10.62(1), 2No2,3No

26. MUSI C MWPC Slit Degrader SC Silicon array NaI array 40 Ti beam Focal plane detectors

27. 40 Ti selection

28. SIS Beam Heavy- ion Decay signal 1 s 5 s 200 ms Other 40 Ti T 1/2 Delayed coincidence technique

29. 40 Ti  -delayed protons IAS, F GT

30. Now: DM = -9096(10) keV, Q EC = 11466(13) keV 4365(8) Trinder et al. 4365(10) This work T z = -2 T z = -1 T z = 0 T z = 1 T z = 2 40 Ti 40 Ar 40 K 40 Ca 40 Sc T = 2 isobars Mass and Q EC for 40 Ti by IAS level energy in 40 Sc using IMME: M(T Z ) = a + b T Z + c T Z 2 Old: DM = -8850(160) keV, Q EC = 11680(160) keV Precise mass determination for 40 Ti

31. 40 Ti  -delayed proton  Half-life 40 Sc IAS level  40 Ti mass Full energy, p-  coin, secondary reaction corrections  F and GT decay strength distributions F/GT distributions

32. B(GT) + B(F) from this work  /B-E x relation from Ormond et al., Phys. Lett. B345(1995)343.  Absorption cross section = 13.8(6)  10 -10 pb with Bahcall et al. 8 B solar neutrino flux of F = 6.6(1.0)  10 6 cm -2 s -1  ICARUS reaction rate 9.1(1.4) SNU (once for two days) =2.6 (Fermi) + 6.5 (Gamow-Teller)  3 times larger than Bahcall predictions W. Liu et al., PRC58(1998)2677 Reaction rates for ICARUS

33. General idea  Production of RIB  Measurement of (d,n) or (d,p) angular distribution  Fit the distribution by DWBA  Get ANC or spec factor  Use ANC or spec factor to deduce (p,  ) astrophysical S-factor or (n,  ) reaction rate H. M. Xu, PRL 73(1994)2027

34. More basics For peripheral transfer reaction: B(d,n)A two virtual captures: B + p  A n + p  d two ANC’s : and known value can be obtained from

35. The Cross Section for E1 capture is the kinetic factor e eff = eN/A for Protons -eZ/A for Neutrons ANC or spec factor

36. Beijing Tandem national laboratory, CIAE Tandem: 15 MV Cyclotron: 100 MeV p, 200  A

37. RIBs expected

38. CSR in Lanzhou

39. CSR performance CSRmCSRe ion species Accelerated p, C － Up,C － U, RIB, Highly charged ions, Molecules and cluster Energy (MeV/u) (B max =1.4 — 1.6 T) 2350 2800 (p) 900 1100( 12 C 6+ ) 400 520( 238 U 72+ ) 2000 (p) 600 760( 12 C 6+ ) 400 520( 238 U >90+ )  P/P <10 -4 <10 -5  P/  P Momentum Acceptance  0.15%  0.5~1% Emittance  5  mm-mrad  1  mm-mrad

40. Inverse kinematics

41. Primary chamber Dipole Quadruples MCP Secondary chamber IC PSSD Target Slit RNB Gas target Secondary beam line GIRAFFE

42. GIRAFFE Target Dipole Quadrapoles Reaction Wien filter W. Liu, NIMB 204(2003)62

43. Beam quality

44. Secondary beams provided by GIRAFFE

45. Physics of 7 Be  The astrophysical S factor for the 7 Be(p,  ) 8 B reaction at solar energies is a crucial nuclear physics input for the “solar neutrino problem”.  It was proposed that the S factor can be indirectly determined through the asymptotic normalization constant (ANC) extracted from the proton pickup reactions of 7 Be, with an accuracy comparable to that from direct radiative capture or Coulomb Dissociation reaction.

46. High energy neutrino cross section: S 17 (0). Direct measurement Coulomb dissociation This work: first measurement of 7 Be(d,n) 8 B, using ANC method to deduce S 17 factor. A independent cross check. 7 Be(p,  ) 8 B reaction

47. Results － 7 Be W. Liu PRL77(1996)611 NPA 616(1997)131c 7 Be(d,n) 8 B Beam Slits Target EE Er PSSD

48. From angular distribution to S-factor W. Liu, PRL77(1996)611

49.  n n  n p di-neutron or n-n halo? n-p halo 6 He 6 Li [4.05] 0 + (T=1) 3.563 0 + (T=1) 1 + (T=0) F G-T Study of 6 He ( p,n) 6 Li reaction

50. Z. Li, PLB 527(2002)50 Angular distribution to density distribution

51. Physics of 11 C  Proton- and  -capture reactions on proton-rich unstable nuclei of A≤13 involved in the hot pp chains are thought to be another alternative way to the 3  process for transforming material from the pp chains to the CNO nuclei in the peculiar astrophysical sites where the temperature and density are high enough so that the capture reaction becomes faster than the competing β decay  These linking reactions between the nuclei in the pp chains and the CNO nuclei might be of immense importance for the evolution of massive stars with very low metallicities.  One of the key reactions in the hot pp chains is the 11 C(p,  ) 12 N which is believed to play an important role in the evolution of Pop Ⅲ stars.

52. Results － 11 C W. Liu, NPA728 (2003)275 11 C(d,n) 12 N EE Er MRSD

53. Physics of 8 Li  Inhomogeneous model predict that short-lived isotopes are created which allow for more reaction pathways to the heavier elements  Reactions involving short-lived radioactive nucleus 8 Li, 7 Be and 8 B play key role  8 Li generating reactions: 7 Li(n,  ) 8 Li and 7 Li(d,p) 8 Li ，  8 Li destroying reactions: 8 Li( ,n) 11 B, 8Li(n,  )9Li, 8 Li(d,p) 9 Li, 8 Li(d,t) 7 Li, 8 Li(d,n) 9 Be, etc.  8 Li( ,n) 11 B and 8 Li(n,  ) 9 Li are key of them  8 Li has short half life of 0.83 s, so indirect approach is the only way to get (n,  ) rates

54. The quantitative picture APJ429(1994)499

55. Results － 8 Li Z. Li, 2004, Submitted 8 Li(d,p) 9 Li Ep

56. Results for (n,  ) rate Z. Li, 2004, submitted

57. Network calculation N. Shu, Contribution to NIC8

58. E983@DRAGON

59. Summary of what we have done

60. Summary of experiments

61. What we have done GIRAFFE, a tandem based one stage unstable beam facility proved to be effective to produce secondary beams suitable for the study of nuclear astrophysics reactions. Angular distribution measurements of transfer reaction in inverse kinematics, together with DWBA/ANC theoretical approach have been used to study the astrophysical reactions indirectly. The astrophysical S-factors and/or reaction rates for 7 Be(p,  ) 8 B, 11 C(p,  ) 12 N, 8 Li(n,  ) 9 Li were deduced by using the measurements of 7 Be(d,n) 8 B, 11 C(d,n) 12 N, and 8 Li(d,p) 9 Li reactions at the energies of astrophysical interest.

62. What we need  Most astrophysical requirements to nuclear physics are related to RNB.  Novel experimental and theoretical methods have to be applied to meet the astrophysical needs.

63. Conclusion  Nuclear astrophysics is a merging place for novel experiments, theory and imagination  New ideas have to come out to meet the challenge of experiments and to develop theory  A basic understanding of astrophysics will help, communication is needed to track the new astrophysical discovery  Fast developing field of physics of unstable nuclei is a nice counter part to accelerate the study

64. Research Team Bing Guo Gang Lian Weiping Liu Xixiang Bai Baoxiang Wang Sheng Zeng Yun Lu Zhihong Li Shengquan Yan Yongshou Chen Nengchuan Shu Kaisu Wu Youbao Wang Zhanwen Ma Xiaodong Tang NAO, U of Tokyo Toshitaka Kajino CIAE