TAUP2007 Sep , 2007 Sendai, Japan Shiou KAWAGOE The Graduate University for Advanced Studies (SOKENDAI) / NAOJ JSPS Research Fellow T. Kajino, The Graduate University for Advanced Studies (SOKENDAI) / NAOJ H. Suzuki, Tokyo University of Science/NAOJ K. Sumiyoshi, Numazu College of Technology S. Yamada Waseda University

Outline 1 ． Introduction 2. Purpose 3 ． Result and Discussions ・ The adiabatic prompt explosion model ・ The observation of supernova neutrinos 4 ． Summary

Gravitational Collapse Shock wave Supernova Neutrino trapping Neutrino Introduction (1) Collapse-driven Supernova

・ All of kinds of neutrinos are generated. ・ The energy spectrum is different. ・ T < O(100) MeV → Introduction (2) Supernova Neutrinos νeνe νeνe νxνx Energy (MeV) Flux (count / MeV) Wilson’s model ・ The gravitational energy:

The mass squared difference The mixing angle Inverted Normal 23 Introduction (3) Neutrino Oscillations ?

Introduction (4) The Matter (MSW) Effect Inverted L H Normal L H ● H- resonance ： ● L-resonance ： adiabatic non adiabatic adiabatic.. nene m2m2 shock Is large. and Is small. or Is large. Is small. nene

The shock wave is influenced on neutrino oscillation. --MSW effect--- We estimate the supernova neutrino events which observed with Super-Kamiokande and SNO. ★ We study how the influence of the shock wave appears in neutrino oscillations. ★ Can we constrain θ １３ and the mass hierarchy? Purpose

We succeeded in calculating propagation of shock waves from iron core through the envelopes in single step. Density [g/cm 3 ] R [cm] ・ Implicit lagrangian code for general relativistic spherical hydrodynamics Yamada et al One-dimensional simulation Adiabatic prompt explosion model 15Msolar star Woosley and Weaver,1995 The Adiabatic Prompt Explosion Model

Target number Efficiency Distance of supernova → 10kpc Spectrum ( 5 < E < 60MeV) Cross section ☆ Survival Probability of neutrino ☆ Neutrino spectra ☆ Event number spectra Original spectra The Calculation of Event Number

Normal hierarchy Inverted hierarchy ☆ target : pure water (32,000 ｔ ) ☆ ☆ inverted mass hierarchy → The event rates are depending on the parameters. Event rate of Super-Kamiokande Time [s] Event Rate [/s] [shock / no shock] Time [s]

Normal hierarchy Inverted hierarchy Event rate of SNO ・・・ has stopped （≧ ω ≦）. ☆ heavy water (1,000 t) ☆ ☆ normal mass hierarchy → The event rates are depending on the parameters. Event Rate [/s] [shock / no shock]

Result ☆ The event rates of SK change greatly. →θ 13 is large and the hierarchy is inverted. ☆ The event rate of SNO change greatly. →θ 13 is large and the hierarchy is normal. ☆ The event rates of SK and SNO decrease simply. →θ 13 is small.

Summary ☆ The event rates are different depending on the value of θ 13. →There is possibility that we can constrain the parameters whether θ 13 is large or small. ☆ θ 13 is large. →The influence of the shock wave appears to the event rates. →We can suggest the mass hierarchy by the observation. ☆ We will calculate other detector. ☆ Improvement underway Detailed studies of the cooling effect of the proto-neutron star are underway.