原子核の弱電相互作用と超新星ニュートリノ

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1 京都大学物理学第二教室談話会 2010 年 10 月 15 日 原子核の弱電相互作用と超新星ニュートリノ ニュートリノ温度および振動パラメータの決定方法の提案 梶野敏貴 国立天文台理論研究部東京大学大学院理学系研究科天文学専攻

2 Neutrino Physics and Cosmology Today Neutrino Mass Cosmology CMB and LSS constraint from cosmological parameter-fit: Σm ν < 1.3 ev (2s C.L.) W n h 2 < WMAP-5yr, 7yr: Komatsu et al. (2008, 2010) New constraint: CMB + Magnetic Field + n+prim. Anisotropic Stress: Σm ν < 0.8 ev (1s C.L.) W n h 2 < (1s) Nuclear Physics Yamazaki, Ichiki, Kajino & Mathews, PRD (2010), in press. Kojima, Kajino & Mathews, JCAP 02 (2010), n-bb : U 2 ebm b < 1~6 ev 0.1~0.05 ev!? (future) Lesgourgues and Pastor (2006) Neutrino Mass Difference and Hierarchy Particle & Nuclear Physics: Underground Lab. + Long-Baseline Exp. Nuclear Astrophysics: SN Neutrino Nucleosynthesis 2

3 Super-K, SNO, KamLand (reactor ν) determined m 12 2 and θ 12 uniquely. KNOWN Neutrinos Super Kamiokande (atmospheric ν) determined m 23 2 and θ 23 uniquely. + Cabbibo Angle m 12 2 m 23 2 LMS SN-neutrinos: Yokomakura et al. PL B544, 286 Θ 12 Several UNKNOWNs Θ 23 (1)sin 2 2q 13 < 0.1, (2) m 132 = 2.4x10-3 ev 2 (3) δ=cp-phase, (4) Absolute Mass Yamazaki, Ichiki, Kajino, Mathews (2009,2010)

4 Various Physics Targets with wide Neutrino-Energy Range 1.9K CMB Cosmic Background Neutrino Cosmology verification of particle model PURPOSE n e, n m, n t 1. To determine SN-n spectra, i.e. n-temperatures? 2. To determine unknown n-oscillation parameters from SN-nucleosynthesis?

5 Direct sinal of SN neutrinos Kamiokande (1987) Event of the Century!

6 Various roles of n s in SN-nucleosynthesis 8 8 n-process ( 7 Li, 11 B ) NS R-process Explo. Si-burn. ( 60 Co, 55 Mn, 51 V ) n-process ( 138 La, 180 Ta, ) n e n mt MSW High-Density Resonance through θ 13 r ~ 1000 g/cm 3

7 Origin of 180 Ta & 138 La p process 138 La ~ spherical nucleus 180 Ta ~ deformed nucleus g K.Yokoi, Nature (1983) Proposal of s-process origin D.Belic et al., Phys. Rev. Lett. (1999) Measurement of transition probability between the isomer and the ground states K.Wisshak, Phys. Rev. Lett. (2001) Neutron capture cross section of 180Ta Nuclear Eperiment & Theory Goko, Phys. Rev. Lett. (2007) Measurement of (gamma,n) reactions D. Byelilov, Phys. Rev. Lett. (2007) (3He,t) experiments for neutrino-process GT, measured at RCNP: E n < 50 MeV! M.-K.Cheoun et al., (2010), in preparation. 1.82y 179 Ta Supernova neutrino-process: Neutral current r process Nucleosynthesis Theory Woosley, Hartmann, Hoffman, & Haxton, ApJ 356 (1990), 272. Heger et al., Phys. Lett. B 606, 258 (2005) Nucleo-Cosmochronology: Hayakawa, Shimizu, Kajino, Ogawa, & Nakada, PRC 77 (2008), ; 79 (2009)

8 Impact of CEX Reaction on n-process Byelikov + Fujita et al., PRL (2007) measurement of GT strength. A. Heger, Phys. Lett. B 606, 258 (2005) La 180Ta solar system gamma only nc 6MeV cc 4MeV cc 6MeV cc 8MeV Overproduction problem of 180 Ta relative to 138 La! Spin-dipole + multipole forbidden transitions + GT contribute! En = 0 ~ 80 MeV

9 No n-beam experiment yet for n-a X-section! We can use Electro-Magnetic PROBE! Similarity between Electro-Magnetic & Weak Interactions EM-current = V, Weak-current = V - A IV i gv V gv s q ( p p') 2m 2m A gas Weak operator in non-relativistic limit Gamow-Tellar operator = Spin-Multipole operator = 4 He(g, n) 3 He and 4 He(g, p) 3 H s t J J [ [ s r Y r (L) ] ] tt Big-Bang nucleosynthesis with SUSY particle 4 He(n, n ), 4 He(n e, e - ), 4 He(n e, e + ) SN-n nucleosynthesis for determining n-oscillation param

10 Neutrino reactions on 138 La and 180 Ta via charged and neutral currents by the Quasi-particle Random Phase Approximation (QRPA), Cheoun, Ha, Hayakawa, Kajino & Chiba, PR C82 (2010), Ba 138 La 180 Hf 180 Ta

11 Cheoun, Ha, Hayakawa, Kajino & Chiba, PR C82 (2010), Larger Spin-Multipole Contribution GT Dominance 138 Ba 138 La 139 La 138 La + n Total Total GT Spin-Mutipole GT Spin-Mutipole

12 Cheoun, Ha, Hayakawa, Kajino & Chiba, PR C82 (2010), Larger Spin-Multipole Contribution 180 Hf 180 Ta 181 Ta 180 Ta + n Total Total GT Spin-Mutipole GT Spin-Mutipole

13 Excitatoin Energy Problem of Isomer Ratio of 180 Ta Isomer Residual Ratio, isomer / (gs+isomer), is a critical factor for the calculation of 180Ta nucleosynthesis. Linking transitions between K = 1 and 9 bands are extremely weak. 180 Ta g and 180 Ta m couple with each other Photons through intermediate linking transitions. Planck Intermediate states Distribution Intermediate states Photon Flux K=1 K = Ta0 180 Ta g K=9 K = 9 T 1/2 =8.15 h Isomer 180 Ta m T 1/2 > y

14 g i /g 0 G i /G 0 /G Gamma-Decay Widths of Excited States Saitoh et al. (NBI group), NPA 1999, ++ Dracoulis et al. (ANU group), PRC 1998, ++ Total Gamma-Decay Width of 180 Ta m D. Belic et al., PR C65 (2002), Excitation Energy [MeV]

15 In general cases: Formula to calculate time-dependent linking transitions Hayakawa, Kajino, Chiba & Mathews, PR C81 (2010) In the case of 180 Ta: Transition probabilities Experimental Data

16 Calculated Result Hayakawa, Kajino, Chiba & Mathews, PR C81 (2010), Pi = 0.39 Present linking dynamical cal. We carried out timedependent dynamical calculations to obtain Pi ~ This result is almost independent of SN models, i.e. total explosion E, progenitor mass, n-luminosity and its decay time scale.

17 Our New Result 138La 138La 138La 180Ta 180Ta 180Ta 180Ta isomer 180Ta isomer T. Hayakawa, T. Kajino, S. Chiba, and G.J. Mathews, Phys. Rev. C81 (2010), (1) We should reduce 180Ta m abundance by a factor Pi = (2) We should use more reliable n-a cross sections, including GT and spin-mutipole transitions solar system gamma gamma only only nc 6MeV cc 4MeV cc 6MeV cc 8MeV nc 6MeV cc 4MeV cc 6MeV cc 8MeV Then, both 138La and 180Ta abundances can be consistently reproduced by the CC-int. of n e and n e of T ne ~T ne = 4MeV.

18 R-Process Yields in Type-II SN n-driven Wind Model Yoshida, Terasawa, Kajino & Sumiyoshi, ApJ 600 (2004) 204 Sasaqui, Kajino, Otsuki, Mathews & Nakamura, ApJ 634 (2005) 1173 Solar System R-abundance Neutron-rich condition takes the key! 2 rd peak r-elements 3 rd peak r-elements actinoids

19 Initial n/p ratio (& Y e ) vs. n-temperatures -1 = = 1.29 MeV = 3.15 x T ne = 3.15 x T ne Neutron-rich condition for successful r-process 0.4 < < 0.5 T ne = 3.2 MeV, T ne = 4 MeV

20 T. Hayakawa, T. Kajino, S. Chiba, and G.J. Mathews, Phys. Rev. C81 (2010), T(n e ) = 3.2 MeV T(n e ) = 4 MeV T(n m,t ) = T(n m,t ) =?

21 S.M. Austin, Prog. Part. Nucl. Phys. 7, 1 (1981) Measured Meteoritic Ratio GCR - 11 B/ 10 B = Measured GCR Ratio

22 Supernova n-process & Key Reactions Yoshida, Kajino & Hartman, Phys. Rev. Lett. 94 (2005), Abundance X A n n ~15% ~85%

23 Overproduction Problem of Supernova- 11 B Hoffman, Woosley & Weaver 2001, ApJ 549,

24 Galactic Chemical Evolution of 9 Be & 10,11 B Livermore Model Tn m,t = 8 MeV Overproduction Woosley & Weaver 1995 ApJS 101, 181. Tn m,t = 6 MeV Yoshida, Kajino & Hartmann 2005, PRL 94 (2005), Be: -Galactic Cosmic Rays OLD stars SUN B + 11 B: -Galactic Cosmic Rays -Supernova n-process Yoshii, Kajino, Ryan 1997, ApJ 486, 605 Ryan, Kajino, Suzuki , ApJ549, 55

25 Grav. Potential constraint Detection of Direct Supernova ns Yoshida, T., Kajino, T., and Hartmann, D., PRL 94 (2005), Consistent with SN1987A! Woosley & Weaver ApJS 101 (1995), 181. OVERPRODUCTION Various progenitor mases Consistent with Thomas-Janka et al (MPA) GCE constraints on 11 B from meteoritic 11 B/ 10 B Yoshida-Kajino-Hartmann (2005)

26 SN n-spectra are now KNOWN! ( n ) / n-oscillation! (1) sin 2 2q 13 < 0.1? (2) m 132 = +/-2.4x10-3 ev 2? (3) δ=cp-phase Yokomakura et al., PL B544, 286 (4) Absolute Mass T(n e ) < T(n e ) < T(n x ) T(n e ) = 3.2 MeV T(n e ) = 4.0 MeV T(n m,t ) = T(n m,t ) = 6.0 MeV e e neutrino spectra T(n e ) < T(n e ) < T(n x ),,, n (MeV)

27 SN1987A ニュートリノを KAMIOKANDE & IMB で検出! 消えた太陽 ( 半電子型 ) ニュートリノの謎 Davis ら 消えた大気 ( ミュー粒子型 ) ニュートリノの謎梶田ら ( 東大 ) 解決案 : 3 世代のニュートリノ (n e n m n t ) は振動して互いに入れ替わる! Pontecorvo (1957) 牧 中川 坂田 (1962) 振動の仕方が完全に解明されていない! q 13, Dm 13, d CP? 目的 超新星ニュートリノ物質振動 (MSW) 効果と元素合成を使って決定する方法の提案! Wolfenstein (1978), Mikheyev & Smirnov (1986) 吉田 梶野ら ( 天文台 / 東大 ) 小柴昌俊ら ( 東大, 1987)

28 H-Resonance Supernova n-process & Key Reactions n MSW (matter) Neutrino Oscillation Effect n ~15% ~85% Additional Charged Current Int. n mt (n mt ) n e (n e ) energetic & energetic

29 SN-Neutrino Oscillation (MSW) Effect on n-process Conversion Probability Adiabatic Non-Adiabatic n e n m n t n e n m n t n e n m n t n e n m n t Center Radius/R sun Center Radius sun - sin 2 2q 13 = 0.04 Parameters: 25M solar SN model (Hashimoto & Nomoto 1999) - m 132 = 2.4x10-3 ev 2 - L n = 3x10 53 erg, t n = 3 sec Fermi-Dirac distr. of n-spectrum, so that the observed 11 B abundance - E ne =12MeV, E ne =20MeV, E nmt =24MeV in Supernova Nucleosynthesis is reproduced.

30 7 Li/ 11 B - Ratio 7 Li/ 11 B Normal Mass Hierarchy MSW Effect: Wolfenstein 1978, PR D17, 2369; Mikheyev & Smirnov 1986, Sov. J. Nucl. Phys. 42, 913. Yoshida, Kajino et al.,2005, PRL94, ; 2006, PRL 96, ; 2006, ApJ 649, 319; 2008 ApJ 686, 448. Astrophysics: Mass Hierarchy m Mixing Angle q 13 No Mixing Inverted Long Baseline Exp: T2K (Kamioka) T2KK (KOREA) Double CHOOZ Daya Bay

31 Metal-poor Halo Stars r-enhanced Observational Signature? 7 Li & 11 B have already been separately detected and measured! SN products Supernova Rem. Presolar SiC Grains X grains from Supernovae

32 Presolar SiC X-grains from SNe ~ 600 SN-Neutrino production (20 M ) 8 P. Hoppe et al. ApJ 551 (2001) 478. Galactic Cosmic Ray production

33 Hamiltonian Dependence of n-a cross section? 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), : QRPA SFO 12 C(n e,e - ) 12 N 12 C(n e,e - ) 12 N(gs,1 + ) GT

34 Hamiltonian Dependence of MSW-Effect on 7 Li/ 11 B Previous SM-s n (E) of Haxton Woosley, Haxton, Hoffmann, Wilson, ApJ. (1990). Hoffmann & Woosley, ApJ. (1992). New SM-s n (E) using WBP( 4 He) & SFO( 12 C) interactions Suzuki, Chiba, Yoshida, Kajino & Otsuka, Phys. Review C74 (2006), normal Normal 0.6 inverted Inverted Normal / inverted, well separated! 7 Li/ 11 B-ratio is SM independent! Mixing angle θ 13 dependence, almost the same!

35 SUMMARY n-process (especially on 180 Ta) and r-process nucleosyntheses in core-collapse SNe provide unique tool to determine the neutrino spectra. Neutron star properties are almost independent on progenitor mass and others. T(n e ) = 3.2 MeV, T(n e ) = 4.0 MeV T(n m,t ) = T(n m,t ) = 6.0 MeV SN n-process on Li-Be-B isotopic ratios are sensitive measure of the MSW effect in order to determine the unknown n-oscillation parameter q 13 and mass hierarchy of active n e, n m, n t. X(SN)-grains search & SN-remnant spectr. obs. Precise theoretical studies of n-nucleus interactions and experimental studies of spin-isospin responses in nuclear structure & reactions are critically important.