Chang-Hwan Gamma-Ray Burst Progenitors

2 Contents Introduction to GRB Long-soft GRB progenitors HMBH Black Hole Binaries Hypernovae Short-hard GRB progenitors NS/low-mass BH binaries Gravitational waves Motivations

3 Gamma-Ray Burst Duration: milli sec - min 1970s : Vela Satellite 1990s: CGRO, Beppo- SAX 2000s: HETE-II, Swift GRB

Cosmological Origin of GRBs 4

5 Two groups of GRBs  Long-duration Gamma-ray Bursts: => HMBH Binaries  Short Hard Gamma-ray Bursts: Duration time NS-NS, NS-BH Binaries GRB

6 Contents Introduction to GRB Long-soft GRB Progenitors HMBH Black Hole Binaries Hypernovae Short-hard GRB Progenitors NS/low-mass BH binaries Gravitational waves HMBH (High-mass black hole) 5-10 solar mass L-GRB ApJ 575 (2002) 996 ApJ 671 (2007) L41

7 L ONG - DURATION GRB S short long BATSE Sample L-GRB Afterglow => Host Galaxy Association => Distance Estimation 7

8 GRB/Supernova Association Afterglow GRB SN1998bw L-GRB

9 Kelly et al., arXiv: Type Ic No H, No He consistent with L-GRB afterglow observation L-GRB

10 Candidates for Type Ic SN / L-GRB No H, No He line WR stars: very massive single progenitor ( > 35 Msun) - loss of hydrogen envelope due to strong wind - slow final rotation Massive progenitors in binaries ( > 20 Msun) - loss of hydrogen envelope due to common envelope evolution - fast final rotation L-GRB

11 What caused GRB/Supernova (Type Ic) ? Most-likely Rapidly rotating Black Holes Callapsar: Asymmetric Explosion of a Massive Star Most-likely Rapid-Rotation L-GRB

Giant Star Formation of black hole Hyper accretion black hole 12

A Generic GRB Fireball central photosphere internal external shocks engine shocks (reverse & forward) gamma-ray UV/opt/IR/radio gamma- ray X-ray UV/optical IR mm radio at birth 13

GRB GRBs produced by forward & backward shocks 14

15 How to form rapidly spinning black holes? Most likely in binaries Companion star can keep the BH progenitor rotating Formation of rapidly rotating stellar mass BHs How to form rapidly spinning black holes to trigger GRBs/Hypernovae ? L-GRB Are there evidences in observation? YES !

16 Discovery of X-ray BH Binaries Mass accretion from a companion star to a compact object X-rays HMBH Binary Soft X-ray transients (Observed BH Binaries)

17 Oscillating Brightness (GRO J ) X-ray & Optical Telescopes HMBH Binary

18 Nova Sco 94 NOMgSiSTiFe [Xi/H] error [Xi/H]: logarithmic abundances relative to solar Israelial et al. 1999, Nature m=2M sun ; M BH =6M sun It’s impossible for normal stars! Where did they come from? HMBH Binary

19 Abundances in the secondary of Nova Sco 94 Hypernova to explain the observations. NOMgSiSTiFe [Xi/H] error They had to come from black hole progenitor when it exploded. HMBH Binary

20 System velocity (-106 km/s) : Abrupt Mass Loss by Explosion Another evidence ? C.M. Mg,Si,S,… HMBH Binary

21 Hypernova Explosions from Rotating BH High Black Hole Mass ( > 5 Msun) --- Maximum Neutron Star Mass < 2 Msun Evidences of BH Spin in BH Binaries HMBH Binary What is the key to trigger the explosion ?

22 Tidal interaction before BH formation rapidly spinning BH at BH birth Fe Synchronization of BH-Progenitor Spin & Binary Orbital Period [ Lee et al. ApJ (2002) ]

23 Preexplosion orbital period (days)  Kerr parameter at BH birth

L INE P ROFILE Doppler effect + Gravitational Redshifts BH Spin Observation Indication of BH spin at BH birth Fabian Miniutti 24

25 Kerr BH Schwarzschild BH at BH birth Innermost stable circular orbit Line Intensity Fabian & Miniutti

Preexplosion orbital period (days)  Rapidly spinning black holes at birth 4U GRO J Shafee et al. (2006) at BH birth Sources for GRB & Hypernovae at birth Lee et al. ApJ (2002) 26

27 HN/GRB Reconstructed BH Binaries at Birth BH Spin – 10000/sec at BH birth

A VAILABLE BH S PIN E NERGIES ? at birth Blandford-Znajek 28

Kerr parameters & Available Energy L-GRBs at birth Soft X-ray transients (Observed BH Binaries) 29

30 Long-soft GRBs Progenitors Spin of Stellar Mass BH in BH binaries Spin of stellar-mass BHs : - tidal (BH progenitor spin-orbit) synchronization is consistent with the current BH spin observation Rapidly-Spinning BH can power both GRB & Hypernovae L-GRBs and Hypernovae : - Short orbital period ( P<0.5 day) HMBH binaries are the relics of L-GRBs and Hypernovae Conclusions L-GRB

31 Contents Introduction to GRB Long-soft GRB Progenitors HMBH Black Hole Binaries Hypernovae Short-hard GRB Progenitors NS/low-mass BH binaries Gravitational waves low-mas Black Hole 2-3 solar mass SH-GRB

32 S HORT - HARD GRB S hard soft shortlong Origin NS-NS, NS-BH merger No Early Optical Afterglow, yet BATSE Sample SH-GRB Any coincidence with GW ? Any information on the inner structure of NS ? 32 UFFO

33 Science 308 (2005) 939 Short-Hard Gamma-ray Burst : Colliding NS binaries Very Important for Gravitational Waves, too GRB

34 Laser Interferometer Gravitational Wave Observatory LIGO I : in operation (since 2004) LIGO II: in progress (2014 ?) GRB

NS (radio pulsar) which coalesce within Hubble time (1975) (1990) (2003) (2004) (2004) (1990) (2000) Globular Cluster : no binary evolution White Dwarf companion Not important Motivations 35

36 Wanted by UFFO Existence of early optical afterglow of GRBs, especially Short-hard GRBs ? If exist, what UFFO can tell us about the physics of GRBs? Can UFFO tell something about the inner structure of NS ? UFFO

37 Thank You !

38 Extra Slides

39 Contents Introduction to GRB Long-soft GRB Progenitors HMBH Black Hole Binaries Hypernovae Short-hard GRB Progenitors NS/low-mass BH binaries Gravitational waves low-mas Black Hole 2-3 solar mass SH-GRB Physics Reports 462 (2008) 1 Brown, CHL, Rho

40  proton, neutron: u, d quarks  By introducing strange quark, we have one more degrees of freedom, energy of the system can be reduced!  In what form ? Kaon, Hyperons … … Why Strange Quarks in Neutron Stars ? Kaon is the lighest particle with strange quark ! maximum M NS Inner structure of NS can be revealed by UFFO?

41 Kaon Condensation in Dense Matter maximum M NS Chemical Potential

42 “Neutron/Strange/Quark” Star maximum M NS

43 Astrophysical Implications Neutrinos Formation of low mass Black Hole Neutron Star Reduce Pressure maximum M NS Soft EoS

44 Black Holes Neutron Stars maximum M NS Mass of stable NS NS without kaon BH with kaon condensation

Masses of Radio Pulsars NS-NS NS-WD Large uncertainty due to WD mass determination NS observation

46 All well-controlled observations are consistent with lower maximum NS mass (soft equation of state). Those observations with higher NS mass cannot rule out the soft equation of state, yet. Short summary on NS observations NS observation

Giant Star Formation of black hole/neutron star Hyper accretion black hole or neutron star 47

48 NS/BH formation from Giant Stars There are a lot more Black Holes (unseen) than we thought !! Mass of Iron Core < 1.5 Msun : NS > 1.5 Msun : BH Hyper accretion

49 H red giant He red giant NS 90%10% A B Life time H He He +0.7 Msun +0.2 Msun Hypercritical Accretion: First born NS should accrete 0.9 M ⊙ !  > 10% A B Hyper accretion

y-axis: final mass of first-born NS in NS-NS Binaries, if they can stay as NS NS-BH should be more dominant than NS-NS GW & SHB NS-BH NS-NS Lee et al., ApJ 670, 741 (2007) 50

51 Why we don’t see BH-NS Binary ? Pulsar life time : 1/B Fresh pulsar : B=10 12 G NS-NS: First-born NS is recycled by accretion B=10 8 G (large chances to be observed) BH-NS: No recycled pulsar Second fresh pulsar doesn’t live long ! Hyper accretion

52 Short-Hard Gamma-ray Bursts (SHBs)  Observed NS-NS binaries are inconsistent with SHBs  Invisible old ( > 6 Gyr) NS binaries are responsible for short-hard gamma-ray bursts (SHBs) invisible old NS binaries are consistent with our NS-BH Binaries Nakar, Physics Reports GW & SHB Lee et al., ApJ (2007)

53 NS + LMBH Binaries as GW source unseen “ NS+LMBH ” are 6 times more dominant than seen “ NS+NS ” system. “ NS+LMBH ” system may increase LIGO detection rate by factor of about 10. GW & SHB Hypercritical Accretion

54 NS/Low-mass BH binaries Maximum mass of NS : - soft equations of state predict lower NS masses Observations : - most NS masses in binaries are still consistent with soft equations of state (prefer lower NS mass). - some indications for higher NS masses Hypercritical accretion : - NS/LMBH should be much more dominant than NS/NS due to hypercritical accreiton Gravitational waves & Short-Hard GRBs : - Advanced LIGO should see 10 times more mergers than predicted by NS/NS binaries - invisible NS/LMBH binaries are consistent with SHBs NS/LMBH