Italian-Korean@sejong

1. Italian-Korean@sejong Double Neutron Star Binaries: Implications for LIGO Chang-Hwan Lee @

2. Science 308 (2005) 939

3. Gravitation Wave from Binary Neutron Star B1913+16 Hulse & Taylor (1975) Effect of Gravitational Wave Radiation 1993 Nobel PrizeHulse & Taylor LIGO was based on one DNS until 2002

4. NS (radio pulsar) which coalesce within Hubble time (2003)(2004) (1990) (2004) (1975) (1990)(2000) Not important Globular Cluster : no binary evolution White Dwarf companion

5. Kalogera et al. (2004) Due to J0737-3039 LIGO detection rate was increased by 8 ! weak radio signal: 1/6 of B1913+16 short coalesce time: 1/2 of B1913+16 Initial LIGO 0.035 event/year Advanced LIGO 187 event/year

6. Q) Why is it so important to Bethe/Brown/Lee scenario ? • Consistent with • 20 more LMBH/NS mergers for LIGO than NS/NS mergers

7. All masses are < 1.5 M⊙ • 1534, 2127: masses are within 1% • J0737, J1756: DM = 0.1 - 0.2 M⊙

8. Why MNS < 1.5 M⊙in Double NS binaries ? • MNS(max)=1.5 M⊙ from dense matter physics • Binary evolution is consistent with MNS(max)=1.5 M⊙ independently of dense matter physics argument. Kaon condensation, etc

9. Maximum Mass of NS Kaon Condensation in Dense Matter

10. Astrophysical Implications Neutron Star Neutrinos Reduce Pressure Formation of low mass Black Hole

11. Maximum Mass of NS Black Holes Neutron Stars

12. Smoking guns for Strangeness SN 1987A • Formation of 1.5 Msun NS : theoretically confirmed by neutrino detection (2002 Nobel prize) • No evidence of NS, yet. (e.g., no Pulsar signal) • NS went into Small Mass Black Hole (by cooling & accretion) !! Masses of Binary Radio Pulsars < 1.5 Msun

13. 1.5

14. Why MNS < 1.5 M⊙in Double NS binaries ? • MNS(max)=1.5 M⊙ from dense matter physics • Binary evolution is consistent with MNS(max)=1.5 M⊙ independently of dense matter physics argument. Kaon condensation, etc

15. Hypercritical Accretion • Eddington Accretion Rate : 10-8 solar mass /year photon pressure balances the gravitation attraction • If this limit hold, neutron star cannot be formed from the beginning. • Neutrinos can take the pressure out of the system allowing the hypercritical accretion when accretion rate is bigger than 104 Eddington limit ! (T > 1 MeV : Thermal neutrinos dominates !) Q) What is the implications of hypercritical accretion ?

16. Fe core mass Neutron Star In Binaries

17. Evolution of binary stars <1% A Life time 10% B 90% He H red giant super giant Original ZAMS(Zero Age Main Sequence) Stars • Probability = 1/M2.5 • Life Time = 1/M2.5 • DM=4%, DTlife=(1 - 1/1.042.5)= 10%, DP=10% (population probability)

18. H red giant He red giant A NS Life time 90% 10% NS B A H He He B +0.2 Msun +0.7 Msun Case 1 : DT > 10% Hypercritical Accretion: First born NS should accrete 0.9 M⊙ !

19. H red giant He red giant A NS Life time NS B H common envelope H A He B +0.2 Msun No accretion Case 2 : DT < 10% First born NS should accrete only 0.2 M⊙ !

20. A NS Life time NS B H common envelope H He A He H B He common envelope Case 3 : DT < 1% No accretion : same mass pulsars !

21. Companion Mass 2.1 M⊙ 2.4 M⊙ DTZAMS > 10%DMZAMS > 4% Case 1. DMNS = 0.9 M⊙2. DMNS = 0.2 M⊙3. DMNS = 0 P=90% ☞ Black Hole DTZAMS < 10%DMZAMS < 4% 1.4 M⊙ 10% 1.7 M⊙ 1.2 M⊙ <1% 1.5 M⊙ 1.2 M⊙ 1.5 M⊙ MNS

22. Why we don’t see BH-NS Binary ? Pulsar life time : 1/B Fresh pulsar : B=1012 G • NS-NS: First-born NS is recycled by accretion B=108 G (large chances to be observed) • BH-NS: No recycled pulsar Second fresh pulsar doesn’t live long !

23. R0=17 Mpc (initial LIGO), 280 Mpc (advanced LIGO)

24. Main points by Bethe/Brown/Lee • Recent DNS J0737-3039 increased NS/NS merger rate by factor 8. • NS/LMBH is 10 times more dominant than NS/NS due to hypercritical acctetion. • NS/LMBH will increase LIGO detection rate by factor of 20.

25. This work (Bethe/Brown/Lee)is his last scientific work in his life !