1. ニュートリノ原子核反応 ーー核子共鳴領域におけるニュートリノ反応模型の構築 超新星爆発中での重陽子を含むニューリノ放出過 程ーー 中村 聡 ( 京大基研 )

2. 核子共鳴領域におけるニュートリノ反応模型の構築 Neutrino-induced forward meson-production reactions in nucleon resonance region H. Kamano, S.X. Nakamura, T.-S.H. Lee, T. Sato Phys. Rev. D 86 (2012) 097503

3. Contents ★ Introduction  scattering in resonance region  ★ Dynamical coupled-channels (DCC) model for    ★ PCAC-based application of DCC model to    (Q 2 =0) Axial current is derived with PCAC from    X amplitudes

4.     Daya-Bay, RENO, T2K, MINOS, Double-Chooz) Next-generation exp.  leptonic CP, mass hierarchy  nucleus scattering needs to be understood more precisely Wide kinematical region with different characteristic  Combination of different expertise is necessary Collaboration at J-PARC Branch of KEK Theory Center http://j-parc-th.kek.jp/html/English/e-index.html & poster LBL

5. Resonance region  2nd 3rd Many nucleon resonances in 2 nd and 3 rd resonance region (MeV)

6. Previous models for induced 1  production in resonance region Rein et al. (1981), (1987) ; Lalalulich et al. (2005), (2006) Hernandez et al. (2007), (2010) ; Lalakulich et al. (2010) Sato, Lee (2003), (2005) resonant only + non-resonant (tree-level) + rescattering (  N unitarity)

7. Resonance region  2nd 3rd Not only 1  production but also … Multi-channel reaction  2  production is comparable to 1    productions (background of proton decay exp.) (MeV) (Data)

8. Dealing with multi-channel reaction Unitary coupled-channel model needs to be developed  Unitarity is missing in previous models  Important 2  production model is missing  Previous models for  and  production are not well tested by data Problems ★ Dynamical coupled-channels (DCC) model for    ★ Application to   

9. DCC model for    Kamano, Nakamura, Lee, Sato

10. Coupled-channel unitarity is fully taken into account

11. DCC analysis of meson production data Fully combined analysis of    (W ≤ 2.1 GeV) ~380 parameters (N* mass, N*  MB couplings, cutoffs) to fit ~ 20,000 data points

12. Partial wave amplitudes of pi N scattering Kamano, Nakamura, Lee, Sato, 2012 Previous model (fitted to  N   N data only) [PRC76 065201 (2007)] Real partImaginary part

13. Kamano, Nakamura, Lee, Sato, 2012 Vector current (Q 2 =0) for 1  Production is well-tested by data

14. Eta production reactions Kamano, Nakamura, Lee, Sato, 2012

15. Vector current (Q 2 =0) for  Production is well-tested by data

16. KY production reactions 1732 MeV 1845 MeV 1985 MeV 2031 MeV 1757 MeV 1879 MeV 1966 MeV 2059 MeV 1792 MeV 1879 MeV 1966 MeV 2059 MeV Kamano, Nakamura, Lee, Sato, 2012

17. Vector current (Q 2 =0) for  Production is well-tested by data

20. Short Summary  scattering in resonance region is multi-channel reaction Unitary coupled-channels model is ideal DCC model for    is developed Model is extensively tested by    data  reliable vector current to be applied to -scattering

21. PCAC-based application of DCC model to forward    Kamano, Nakamura, Lee, Sato, PRD 86 (2012) 097503

22. Objectives  Set a starting point for full dynamical model  Relative importance of different channels  Comparison with Rein-Sehgal model

23. Formalism Cross section for   X ( X =  )    Q2Q2 CVC & PCAC LSZ & smoothness Finally    X  is from our DCC model

24. Results SL NN  N  NN   Prediction based on model well tested by data   dominates for W ≤ 1.5 GeV   becomes comparable to  for W ≥ 1.5 GeV  Smaller contribution from  and  Y O (10 -1 ) - O (10 -2 )  Agreement with SL (no PCAC) in  region

25. Comparison with Rein-Sehgal model  Non-resonant mechanism is included in RS model  Lower  peak of RS model  RS overestimate in higher energy regions (DCC model is tested by data) Comparison in whole kinematical region will be done after axial current model is developed

26. Summary DCC model for forward    via PCAC   Prediction based on model well tested by data   comparable to  for W ≥ 1.5 GeV (first     First    Y calculation based on data Comparison with Rein-Sehgal model :  RS has Lower  peak  RS overestimates cross section at higher energies Full development of dynamical axial current is underway

27. 超新星爆発中での重陽子を含むニューリノ放出過程 那須、佐藤（阪大）、中村（基研）、住吉（沼津）、久保寺、 Myhrer (South Carolina)

28. Neutrino reactions on the deuteron Important relevance to neutrino physics, astrophysics Supernova (  heating,  emission)  oscillation experiment @ SNO Solar fusion (pp-chain)

29. Contents Calculational method  heating in supernova  emission in supernova

30. Calculational method Well-established method for electroweak processes in few-nucleon systems AV18, Nijmegen, Bonn, etc.

35. Most recent applications of the model to weak processes ★ Muon capture (, ), Marcucci et al., PRC 83 (2011) [1] [2] Theory MuSun@PSI [3] Theory ★ pp-fusion ( ) for solar model, Schiavilla et al. PRC 58 (1998) ★ d-reactions (, ) for SNO experiment SN et al. PRC 63 (2000) ; NPA707 (2002)  evidence of -oscillation, solar problem resolved [1] Cargnelli et al. (1998) [2] Bardin et al. NPA 453 (1986) [3] Ackerbauer et al. PLB 417 (1998)

36. Neutrino-deuteron reaction as heating mechanism in Supernova SXN, K. Sumiyoshi, T. Sato, PRC 80, 035802 (2009) In many simulations, supernova doesn’t explode !  extra assistance needed for re-accelerating shock-wave ★ neutrino absorption on nucleon (main) ★ neutrino scattering or absorption on nuclei (extra agent) NC can contribute to the heating

38. Abundance of light elements in supernova Sumiyoshi, Röpke, PRC 77, 055804 (2008) 15 M , 150 ms after core bounce Nuclear statistical equilibrium assumed cf. Arcones et al. PRC 78, 015806 (2008)

39. Energy transfer cross section CC (absorption) NC (scattering) Thermal average

40. Thermal average of energy transfer cross sections 3 H (  Arcones et al. PRC 78 (2008) 4 He(  : Haxton PRL 60 (1998) _ 3 He (   O’conner et al. PRC 78 (2007) 4 He (  : Gazit et al. PRL 98 (2007) Results

41. Thermal average of energy transfer cross sections

42. Electron capture on deuteron & NN fusion as neutrino emission mechanism S. Nasu, SXN, T. Sato, K. Sumiyoshi, F. Myrer, K. Kubodera

43. -emission previously considered (A≤2) New agents

44. Emissivity (Q)

45. Supernova profile Sumiyoshi, Röpke, PRC 77, 055804 (2008) 150 ms after core bounce Nuclear statistical equilibrium assumed

46. e -emissivity e - p, e + e - : Bruenn, ApJS 58 (1985) NN brem: Friman et al, ApJ 232 (1979) Q (e - p) > Q(e - d) > Q (NN  d) Deuterons exit at the cost of the proton abundance +  (e - p) >  (e - d)  Effectively reduced e  emissivity  less  flux, -heating, slower deleptonization & evolution of proto-neutron star  Need careful estimate of light element abundance & emissivity

47. Reduction of e -emissivity

48. e -emissivity Q (e + n) > Q(e + d) > Q (NN  d) _

49. e -emissivity _ (inner region proto-neutron star) np  d e  e  could be important ! _

50.  -emissivity Q (NN brem) ≈ Q (np  d) Whenever NN brem is important, np  d can be also important  Possible important role in proto-neutron star cooling

51. Summary Deuteron breakup & formation in SN and NS for -heating & emission Framework : NN wave functions based on high-precision NN potential + 1 & 2-body nuclear weak currents (tested by data) -heating: Substantial abundance of light elements (NSE model) for deuteron : much larger than those for 3 H, 3 He, 4 He 25-44% of for the nucleon

52. Summary -emission: New agents other than direct & modified Urca, NN bremsstrahlung Emissivities  Rigorous evaluation of nuclear matrix elements No long wave length limit, no Born approximation Electron captures  effectively reduced e emissivity  Need careful estimate of light element abundance & emissivity NN fusions  np  d  could be important for e &  emissivites  play a role comparable to NN bremsstrahlung & modified Urca   need careful study of deuteron in dense matter _ _

53. Backups

54. Exchange vector current ★ Current conservation for one-pion-exchange potential ★ VN  coupling is fitted to np  d  data

55. Comparison with np  d  data Exchange currents contribute about 10 %

56. Emissivity (Q)

57. Approximation ! 3 dimensional integral

58. Previous common approximation to evaluate Q NN-brem One-pion-exchange potential, Born approximation Neglect momentum transfer ( )  also angular correlation between and Nuclear matrix element  long wave length limit  constant _

59. Compilation I : Shen EoS, N, 4 He, a heavy nucleus Compilation II : light elements abundance from Sumiyoshi & Röpke (2008) Both have the same density, temperature, electron fraction Emissivites from direct Urca, e + e - annihilation, NN brems  compilation I Emissivites from election captures on d & NN fusion  compilation II

60. Meson exchange current effect on Q Large effect on NN fusion !

61. Why so large meson exchange current effect ? ★ Higher NN kinetic energy invites large exchange current effect ★ Axial exchange current & higher partial waves are important ; uncertainty

62. Neutrino spectrum

63. BACKUP

64. Comparison with Rein-Sehgal model  Non-resonant mechanism is included in RS model  Lower  peak of RS model  RS overestimate in higher energy regions (DCC model is tested by data) Comparison in whole kinematical region will be done after axial current model is developed

65. F 2 from RS model

67. Spectrum of N* resonances Real parts of N* pole values L 2I 2J PDG 4* PDG 3* Ours Kamano, Nakamura, Lee, Sato,2012

68. SL model applied to  nucleus scattering 1  production Szczerbinska et al. (2007)

69. SL model applied to  nucleus scattering coherent  production   C       C    C    - +     C Nakamura et al. (2010)

70. Dealing with multi-channel reaction e.g., -induced  production Tree-level models  S=0 : Adera et al., (2010)  S=1 : Rafi Alam et al., (2010), (2012)

71. DCC model for    reactions For analyzing data to identify nucleon resonances (Baryon spectroscopy) * Well-established meson-exchange mechanism for meson-baryon interactions * Description of nucleon resonance (N*)  N B M N* * Unitarity   coupled-channels