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Neutrino-Induced Reactions on Fe and Ni Isotopes and Nucleosynthesis in Stars Toshio Suzuki Nihon University. NDM09, Madison, Wisconsin Sept. 2, 2009. New evaluation of reaction rates in fp-shell and light (p-shell) nuclei ● New shell model Hamiltonians
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Neutrino-Induced Reactions on Fe and Ni Isotopes and Nucleosynthesis in StarsToshio Suzuki Nihon University NDM09, Madison, Wisconsin Sept. 2, 2009
New evaluation of reaction rates in fp-shell and light (p-shell) nuclei ● New shell model Hamiltonians ● ν-12C, ν-4He reactions evaluated by new shell model Hamiltonians (SFO, WB) ・Synthesis of 7Li, 11B in supernovae ● GT strength in Fe and Ni isotopes evaluated by a new Hamiltonian, GXPF1 ・ν-56Ni reaction and synthesis of55Mn in Pop. III star ・e-capture on 56Ni, 52Fe and Fe, Ni isotopes ・ν-52Fe reaction (and synthesis of51V)
New Shell-Model Hamiltonians newconventional p-shell(p-sd) SFO, OFUvsCK+MK sd-shell(sd-fp) SDPFM vsUSD+MK fp-shell(fp) GXPF1 vs KB3 SFO: Suzuki, Fujimoto, Otsuka, PR C67, 044302 (2003) OFU: Otsuka et al., PRL 87, 082502 (2001) CK: Cohen-Kurath, Nucl. Phys. 73, 1 (1965) MK: Millener-Kurath, Nucl. Phys. A255, 315 (1975) SDPFM: Utsuno et al., PR C60, 054315 (1999) GXPF1: Honma et al., PR C65, 061301 (2002); C69, 034335 (2004) USD: Brown-Wildenthal, Ann. Rev. Nucl. Part. Sci. 38, 29 (1988) KB3: Caurier et al., Rev. Mod. Phys. 77, 427 (2005)
SFO p-sd shell Suzuki, Fujimoto, Otsuka, PR C67 (2003) Tensor components Shell evolution in N=8 isotone N=8 N=6 πp3/2
Monopole terms Ni Z=28 Z=28 g9/2 Otsuka, Suzuki …, PRL 95, 232502 (2005) Honma et al., PR C69, 034335 (2004)
Magnetic moments of p-shell nuclei B(GT) values for 12C -> 12N SFO B(GT) values for 14N -> 14C SFO present = SFOSuzuki, Fujimoto, Otsuka, PR C67 (2003) Negret et al., PRL 97 (2006) Space: up to 2-3 hw KVI RCNP SFO*: gAeff/gA=0.95 B(GT: 12C)_cal = experiment
Nucleosynthesis processes of light elements LSND Athanassopoulos et al. PR C55, 2078 (1997) Suzuki, Chiba, Yoshida,Kajino, Otsuka, PR C74, 034307, (2006).
Cross sections for Supernova Neutrinos with temperature T Proton and neutron emissionsBR: Hauser-Feshbach model νSpectra
Abundances of 7Li and 11B produced in supernova explosion processes M=16.2 M☼ (SN 1987A) No oscillation case Suzuki, Chiba, Yoshida, Kajino and Otsuka, PR C74, 034307 (2006)
fp-shell: New features in GXPF1 by Honma et al. KB3G A = 47-52 KB + monopole corrections G: improved gap, 3: fine tuning in Vfr (A = 50 -52) GXPF1 A = 47-66 ○ More attraction for T=0 m.e. than G-matrix E(1p3/2) – E(0f7/2) ~ 3 MeV cf. ~ 2 MeV for KB3, FPD6 New magic number at N = 34cf. N = 32 for KB3, FPD6 ○ r.m.s deviations from observed valuesGXPF1 vs KB3G Z, N <28; Z<28, N>28: similar Z or N =28 (56Ni, 55Co, 57Ni); Z, N>28: smaller for GXPF1 Core excitations are better described by GXPF1 than by KB3G ○ Monopoles GXPF1 vs KB3G 1p-1p part differ GXPF1: not a constant shift (J-dependence) ○ Systematic description of 21+ energies in Ni, Ca, Ti, Cr, Fe isotopes cf. KB3G 56Ni : Ecal – Eexp ~ 2 MeV ○ Soft 56Ni-core (f7/2)16: 69% (GXPF1), 49% (FPD6) B(GT+): 11.3 (GXPF1), 10.1 (KB3), 13.7 (closed core)
E(2+) B(E2) Ca: New magic number at N=34 56Ni = soft core Magnetic moment exp Free geff
Soft-56Ni core: 58Cu 56Ni-core Breaking of 56Ni-core 48Ca-core Lisetskiy et al., PR C68, 034316 (2003) Cocolios (2009) GXPF1 Mag. mom. of 57-69Cu (N=28-40) well described by GXPF1 Minamisono et al, PRL 96 (2006)
8-12MeV 7-12MeV 7-12MeV 8-13MeV fp-shell B(GT) for 58Ni M1 strength (GXPF1J) Honma Exp: Fujita et al. gAeff/gAfree=0.74
GXPF1J Honma et al. cf. KB3 Caurier et al. B(GT)=9.5 B(GT)exp=9.9±2.4 B(GT)KB3G=9.0
GXPF1J Honma et al. 1+: shell-model 0-, 1-, 2- etc. : RPA gAeff/gAfree=0.74 Quenching of M2 strength in 48Ca and 90Zr gSeff=0.64gS P. von Neumann-Cosel et al., PRL 82, 1105 (1999)
B(GT-) GXPF1J EXP. 54Fe 7.3 7.8+/-1.9 56Fe 9.5 9.9+/-2.4 58Ni 8.0 7.4+/-1.8 60Ni 9.9 7.2+/-1.8 B(GT+) GXPF1J EXP. 54Fe 4.0 3.3+/-0.5 56Fe 2.9 2.8+/-0.3 58Ni 4.7 3.8+/-0.4 60Ni 3.4 3.1+/-0.1
Neutral current reaction on 56Ni B(GT)=6.2 (5.4) GXPF1J (KB3G)
Synthesis of Mn in Population III Star cf: HW02 gamma p n
Yoshida, Umeda, Nomoto [Mn/Fe] No ν -0.53 HW02 -0.29 [Mn/Fe] GXPF1J(GT) -0.25 GXPF1J(GT)×2 -0.17 GXPF1J(all) -0.19 KB3G(GT) -0.32 KB3G(GT)×2-0.27 No ν With ν(GXPF1J) With ν x2 With ν(Woosley)
GXPF1J KB3G B(GT): 4.43 3.86 E_av: 5.50 4.86
Neutral current reaction on 52Fe B(GT)=4.43 (3.86) for GXPF1J (KB3G)
Production of 51V in supernovae ->Enhancement of production yield of 51V
Summary • Successful description of GT strengths in fp-shell and p-shell nuclei by new shell model Hamiltonians • Enhancement of ν-nucleus reaction cross sections: (ν, ν’p) • Enhancement of production yields of 7Li, 11B, and 55Mn in supernovae • Decrease of e-capture rates in Fe and Ni isotopes in steller environment
Collaborators M. Honmad,T. Yoshidab, S. Chibac, K. Higashiyamae, H. Umedaf, K. Nomotof, D.H. Hartmanng, T. Kajinob,f and T. Otsukah bNational Astronomical Observatory of Japan cJapan Atomic Energy Agency dUniversity of Aizu eChiba Institute of Technology FDepartment of Astronomy, University of Tokyo gDept. Of Physics and Astronomy, Clemson University hDepartment of Physics and CNS, University of Tokyo