1. Gravitational waves and neutrino emission from the merger of binary neutron stars Kenta Kiuchi Collaboration with Y. Sekiguchi, K. Kyutoku, M. Shibata Ref.) 1105.5035

2. Introduction Our research target = high energy astrophysical phenomena e.g., Supernova energy ≈ 1.5*10 46 J = energy the Sun consumes for 1.2 trillion years !! SN1054 （ Crab Nebula ） r ～ 1000km ～ 10km ～ Solar mass Energy source = gravitational potential energy ∝ r -1

3. Products of high energy astrophysical phenomena ～ 10km ～ 3km （ 1 Solar mass ） ✓ Density ～ 10 15 g/cm 3 (1.41 g/cm 3 ) ⇒ General Relativity, Strong interaction ✓ Temperature ～ 10 11 K (15.7×10 6 K) ⇒ Weak interaction ✓ Magnetic fields ～ 10 15 Gauss (Sunspot ： several thousand Gauss) ⇒ Electromagnetic force All of fundamental interaction play an essential role.

4. Physical aspects of high energy astrophysical phenomena ✓ Highly dynamical ✓ No special symmetry, e.g., spherical symmetry ⇒ Numerical modeling including four kinds of forces Numerical Relativity Figuring out high energy astrophysical phenomena by numerically solving the Einstein equations

5. Importance of Numerical Relativity ○ Gravitational waves ✓ imprinting “raw” information of sources ✓ extremely weak signal, h c ∼ 10 -22 = the change of (Size of H atoms)/(Distance to Sun) GW detectors Need to prepare theoretical templates of GWs

6. Today’s topic = Coalescence of binary neutron stars ✓ Promising source of GWs ✓ Theoretical candidate of Short-Gamma-Ray Burst ✓ High-end laboratory for Nuclear theory A nuclear theory ⇒ Mass-Radius relation for Neutron Star Image of GRB Black hole + disk? Mass-Radius

7. Overview of binary neutron star merger NS G.Ws. imprint only information of mass G.Ws. imprint information of radius Rapidly rotating massive NS BH and torus M total < M crit M total > M crit ✓ M crit depends on the Equation of State, i.e. M crit = 1.2-1.7 M max ✓ Final massive NS or torus around BH are extremely hot, T ∼ O(10) MeV ⇒ Neutrino cooling plays an importance role

8. Set up of binary neutron star ○ Shen or Shen-Hyperon EOS based on RMF theory (Shen+,98, Sumiyoshi+,11) ⇒ M crit = 2.8-2.9 Solar mass for Shen, 2.3-2.4 Solar mass for Shen-Hyperon EOS ○ Neutrino cooling based on GR leakage scheme (Sekiguchi,10) ○ Equal mass model with 1.35 Solar mass, i.e., M tot =2.7 Solar mass Observed BNSs (Lattimer & Paraksh 06) Mass-Radius Observation constraint by PSR J1614-2230

9. Result Density color contour on equatorial (x-y) plane = orbital plane In units of Kilometer In units of millisecond Log 10 (ρ [g/cc])

10. Gravitational Waveforms Shen Shen-Hyperon NSs orbit around each other BH formation Massive NS oscillates

11. Gravitational Wave Spectrum frequency Amplitude Sensitivity curves for GW detectors Shen Shen-Hyperon GWs could be detected if the merger happens within 30 Mpc.

12. ○ ○ Neutrino cooling timescale ∼ 2-3 second ○ Huge luminosity ∼ 10 53 erg/s ○ Could be detected if it happened within 10 Mpc for HK Neutrino Luminosity Shen Shen+ Hyperon Anti electron neutrino Electron neutrino μ, τ neutrino BH formation

13. Summary ○ Binary neutron star merger Numerical Relativity simulations with microphysical process for the first time ○ GWs could be detected if it happened within 30 Mpc ○ Neutrino could be detected if it happened within 10 Mpc ⇒ Multi messenger astronomy is coming soon !! Thanks to SR16000 in YITP Thank you for your attention