Element Genesis and Cosmic Chemical Evolution R-Process Prespecive

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1 Nishina Hall, RIKEN, October 17-19, st NAOJ Visiting Fellow Workshop on Element Genesis and Cosmic Chemical Evolution R-Process Prespecive Taka KAJINO National Astronomical Observatory Department of Astronomy, University of Tokyo Organizers Wako Aoki, Michael Famiano, Toshitaka Kajino (NAOJ) Shunji Nishimura, Tohru Motobayashi, Shigeru Kubono (RIKEN) Hidetoshi Yamaguchi (CNS), Hiroari Miyatake (KEK) Host: NAOJ Co-host: RIKEN NC Sponsor: UT-CNS, KEK Japan Forum of Nuclear Astrophysics

2 [Eu/Fe] [Ba/Eu] [Ba/Fe] SUBARU Telescope HDS Honda, Aoki et al. (SUBARU/HDS Collaboration), 2004, ApJS 152, 113; 2004, ApJ 607, AGB solar s-ratio 0 Subaru NAO solar r-ratio SN II [Fe/H] SN I + II R-process elements from Type II SNe! 0 Lack due to obs. limit. Early Universe [Fe/H] = log(n Fe /N H ) - log(n Fe /N H ) Large abundance scatter at [Fe/H]<-2 is an evidence for INDIVIDUAL supernova episode. Only Core-Collapse TYPE II SUPER- NOVAE are the likely astrophysical sites of the R-Process!

3 Sneden, Cowan, Gallino, ARAA 46 (2008) 241. HST-obs., Roederer et al., ApJ 747 (2012) L8. log Fe/H Fe/H t y Te = Solar system -3.0 Sr-Y-Zr Ba Eu Au Pb Th U Metal-poor stars UNIVERSALITY!

4 UNIVERSALITY の亜種の発見 (Honda, Aoki, + すばる望遠鏡 HDS チーム ) Universality CS Solar-System Abundance HD Pseudo-Universality

5 Magic Number and Slow/Rapid Neutron-Capture Processes Slow Nautron-Capture Process on stable nuclei in AGB Stars t b << t n (T~10 8 K, n n ~ cm -3 ) RIKEN-RIBF 2010 Fe-Co-Ni: seeds Fe-Co-Ni are g,n-disintegrated! Rapid Nautron-Capture Process on neutron-rich nuclei in SNe R-process starts from p s, n s and a s! t n << t b (T~10 9 K, n n ~ cm -3 )

6 RIKEN-RIBF New Ring Cyclotron (since 2007) 2010, October 2007, March Many nuclei on the r-process path! 132 Sn 2 nd r-peak 78 Ni Seed for r-process

7 Proton Number Z Supernova Nucleosynthesis Simulation S. Chiba n-pair Heated Collapsar Model K. Nakamura, et al. ApJ (2012). 235 U 208 Pb Fe Nishimura, et al. (2011, 2012) Neutron Number N

8 Challenge to identify astrophysical sites of the r-process: n-wind SNe MHD jet SNe NS mergers GRBs + Explosion mechanism Y e > 0.5? R-process Nucleosynthesis K. Otsuki, H. Tagoshi, T. Kajino and S. Wanajo, ApJ 533 (2000), 424; S. Wanajo, T. Kajino, and G. J. Mathews, and K. Otsuki, ApJ J. 554 (2001), 578. n e + n p + e - n e + p n + e + Neutron-rich condition for successful r-process: 0.1 < Y e < 0.48 Sr-Y-Zr I-Xe T ne = 3.2 MeV < T ne = 4 MeV Theoretical model Dy-Er Ir-Pt Pb Roberts, Reddy and Shen(arXiv ) pointed out Y e < 0.5 for nucleon pot. & Pauli blocking. Observed Solar r-abundance A

9 Various roles of n s in SN-nucleosynthesis 8 8 MSW resonance at r~10 3 (g/cm 3 ) n-flavor Oscillation n-n Scattering near Proto-Neutron n-collective Flavor Oscillation n e n mt NS Si Layer R-process: Heavy Nuclei np-process: 92 Mo, 96 Ru? Explo. Si-burn. Fe-Co-Ni, 60 Co, 55 Mn, 51 V n-process 180 Ta, 138 La, 92 Nb, 98 Tc n-process: 6,7 Li, 9 Be, 10,11 B

10 MSW Effect & n Mass Hierarchy Predicted 7 Li/ 11 B-Ratio Yoshida, Kajino et al. 2005, PRL94, ; 2006, PRL 96, ; 2006, ApJ 649, 319; 2008, ApJ 686, Li/ 11 B Normal Mass Hierarchy No Mixing Inverted Astrophysics: Mass Hierarchy m Mixing Angle q 13 Long BaselineExp. in 2011: T2K (Kamioka) MINOS Reactor Exp. in 2012: Double CHOOZ Daya Bay RENO (KOREA) sin 2 2q 13 sin 2 2q 13 = 0.1

11 n-n Scattering & Collective n-scillation H n = Mixing and Interaction with Background Electrons MSW (Matter) Effect: Mikeheev-Smirnov-Wolfebstein (1978, 1985) p 1 n e p 1 n x H nn = Self-Interaction Self-Interaction x N e = electron density p 1 n e p 2 n e p 2 n x p 1 n x Quest for EXACT Many-Body SOLUTION! Invariants of collective neutrino oscillations Y. Pehlivan, A.B. Balantekin, T. Kajino & T. Yoshida Phys. Rev. D84, (2011)

12 n-a reaction cross sections? Haxton s SM cal. (Woosley et al. ApJ. 356 (1990), 272) Suzuki s new SM cal. with NEW Hamiltonian Suzuki, Chiba, Yoshida, Kajino & Otsuka, PR C74 (2006), Suzuki, Fujimoto & Otsuka, PR C67, (2003) SFO 12 C: SFO Hamiltonian = Spin-isospin flip int. with tensor force to explain neutron-rich exotic nuclei. - m-moments of p-shell nuclei - GT strength for 12 C 12 N, 14 C 14 N, etc. (GT) - DAR (n,n ), (n,e-) cross sections Cheoun et al., PRC81 (2010), ; J. Phys. G37 (2010) : QRPA Cal. SFO 12 C(n e,e - ) 12 N 12 C(n e,e - ) 12 N(gs,1 + ) GT

13 Double b decay - n mass - Astro-Cosmology Connection K. Yako et al., PRL 103 (2009) Experiment (RCNP, Osaka) Shell model (theory)

14 Nuclear Astrophysics Programs of Photon- & Lepton-Induced and Charge-Exchange Reactions for the Studies of Element Genesis Ex The developed HI & RIB technique + Intense RI-Beam at RIKEN + High Precision Spectrometer at RCNP Probe any Energy on wide N-Z (Isospin) Understanding of nuclear weak response in astrophysical processes R-process (GT + first forbidden) - SN explosion mechanism - Th-U synthesis & cosmochronology Neutral & Charged currents - LiBeB synthesis & n-oscillation - Fe-Mn synthesis in 1 st generations of star - La, Ta, Nb synthesis & cosmic clock EC/beta-decays - SN II, SN Ia, X-ray bursts Proton-rich (ν,ν ) (ν,e) GDR GTGR, PDR EC, b-decays Z = N R-process Neutron-rich Uesaka Spin-Isospin Labo., RIKEN

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16 All Amino Acids on the Earth, left-handed Why? Chitrality, Earth/Solar origin or Universal? Neutrinos are all left-handed! Supernovae with strongly magnetized neutron star or BH emit intensive flux of neutrinos over yrs! SN ejecta including 14 N interact with neutrino under strong magnetic field! Neutrino- 14 N coupling is asymmetric & chiral selective! Boyd, Kajino, & Onaka (Astrobiology 10 (2010), ) L-handed chirality is UNIVERSAL! Magnetized supernova 14 N lives! % 99.3% 0.61% m e c 2 14 O ν e + 14 N e O Mann and Primakoff (Origins of Life, 11 (1981), 255) suggested β-decay of 14C, but it s too SLOW! 14 N dies! ν e + 14 N e C % C (5730y) 14 N (1+)

17 Macro-Science Astronomy & Astrophysics Element genesis locates in critical position! Micro-Science Nuclear & Particle(n)Physics