Are Ultralong GRBs Caused by Blue Supergiant Explosions, Newborn Magnetars, White Dwarf Tidal Disruption Events? Kunihito Ioka (Center for Gravitational Physics, YITP, Kyoto U.) with Kenta Hotokezaka (Hebrew) Tsvi Piran (Hebrew) arXiv: 1608.02938 ApJ 833, 110 (2016) 2017/01/24 ultralong GRB & TDE by K. Ioka 2 Summary Supernova(-like Event) Lbol (Greiner+15) ] -1 L using unbroken afterglow Collapsar 44 bol 10 PS1-11af (TDE) PTF11rks (SLSN) 1043 98bw (SN) Explosion 52 4 9 -1 Ei=1.4×10 erg, ti=1×10 s, M=3 M , v=2×10 cm s , =0.2 ⊙ 2 Magnetar H=(E/te)/(1+t/te) 50 6 9 -1 E=1.4×10 erg, te=1.1×10 s, M=2.2 M , v=2×10 cm s , =0.04 42 ⊙ 5/3 Bolometric luminosity [erg s 10 Tidal Disruption Event H=(2E/3te)/(1+t/te) 50 5 9 -1 E=2.4×10 erg, te=2×10 s, M=1 M , v=2×10 cm s , =0.2 ⊙ 0 10 20 30 40 50 Rest-frame time after explosion [days] 2017/01/24 ultralong GRB & TDE by K. Ioka 3 Summary Supernova(-like Event) Lbol (Greiner+15) ] -1 L using unbroken afterglow Collapsar 44 bol 10 PS1-11af (TDE) PTF11rks (SLSN) 1043 98bw (SN) Explosion Magnetar 52 4 9 -1 Ei=1.4×10 erg, ti=1×10 s, M=3 M , v=2×10 cm s , =0.2 ⊙ 2 Magnetar H=(E/te)/(1+t/te) 50 6 9 -1 E=1.4×10 erg, te=1.1×10 s, M=2.2 M , v=2×10 cm s , =0.04 42 ⊙ 5/3 Bolometric luminosity [erg s 10 Tidal Disruption Event H=(2E/3te)/(1+t/te) 50 5 9 -1 E=2.4×10 erg, te=2×10 s, M=1 M , v=2×10 cm s , =0.2 ⊙ 0 10 20 30 40 50 Rest-frame time after explosion [days] 2017/01/24 ultralong GRB & TDE by K. Ioka 4 Summary Supernova(-like Event) Lbol (Greiner+15) ] -1 L using unbroken afterglow Collapsar 44 bol 10 PS1-11af (TDE) PTF11rks (SLSN) 1043 98bw (SN) Explosion Magnetar 52 4 9 -1 Ei=1.4×10 erg, ti=1×10 s, M=3 M , v=2×10 cm s , =0.2 ⊙ 2 Magnetar H=(E/te)/(1+t/te) 50 6 9 -1 E=1.4×10 erg, te=1.1×10 s, M=2.2 M , v=2×10 cm s , =0.04 42 ⊙ 5/3 Bolometric luminosity [erg s 10 Tidal Disruption Event H=(2E/3te)/(1+t/te) 50 5 9 -1 E=2.4×10 erg, te=2×10 s, M=1 M , v=2×10 cm s , =0.2 + Tidal ⊙ 0 10 20 30 40 50 Disruption Rest-frame time after explosion [days] Event 2017/01/24 ultralong GRB & TDE by K. Ioka 2 Diversity of GRB Ultra-long GRB GRB 130925A Low-Luminosity GRB Magnetar Tidal Levan+ 14 Disruption Gendre+ 13 Lien+ 16 Event 2017/01/24 ultralong GRB & TDE by K. Ioka Nakauchi+2 13 Kashiyama+ 13 Suwa & KI 11 Collapsar? Nagakura+ 12 Ultra-long GRB GRB 130925A Low-Luminosity GRB Magnetar Tidal Levan+ 14 Disruption Gendre+ 13 Lien+ 16 Event 2017/01/24 ultralong GRB & TDE by K. Ioka 7 Pop III GRB? Present Day GRB Komissarov & Barkov 10 ? Meszaros & Rees 10 Suwa & KI 11 Nagakura, Suwa & KI 12 Envelope accretion ⇒ Ultra-long 2017/01/24 ultralong GRB & TDE by K. Ioka 8 Cooling Envelope? z=0.677 Blue supergiant (BSG) M=75M¤, Z=1e-4Z¤, R=8.6e12cm Ec=1e53 erg, Mc=5.8M¤ Cocoon thermal emission Nakauchi+ 13, 12; Kashiyama+ 13 ≈ Superluminous supernova 2017/01/24 ultralong GRB & TDE by K. Ioka 2 Levan+ 14 Gendre+ 13 TDE? MacLeod+ 14 Ultra-long GRB GRB 130925A Low-Luminosity GRB Magnetar Tidal Levan+ 14 Disruption Gendre+ 13 Lien+ 16 Event 2017/01/24 ultralong GRB & TDE by K. Ioka 10 Swift J1644+57 ~t-5/3 tvar~100sec flare~103-4sec quiescent~5x104s Burrows+ 11 duration~107s 2017/01/24 ultralong GRB & TDE by K. Ioka 11 ULGRB = TDE? Similar? Dissimilar? Evans+ 14 2017/01/24 ultralong GRB & TDE by K. Ioka 12 White Dwarf TDE ⎛ ⎞2 3 ⎛ ⎞−1 3 M BH 12 M* amin ~ ⎜ ⎟ R* ~ 10 cm⎜ ⎟ ⎝ M* ⎠ ⎝ M8 ⎠ ⎛ ⎞2 3 ⎛ ⎞−1 3 M BH ρ* ×⎜ 5 ⎟ ⎜ 6 −3 ⎟ ⎝10 M8 ⎠ ⎝10 g cm ⎠ 1 2 3 ⎛ ⎞− amin 3 M* t0 ~ 2π ~ 4 ×10 sec⎜ ⎟ GM BH ⎝ M8 ⎠ 1 2 −1 2 ⎛ M ⎞ ⎛ ρ ⎞ × BH * a ⎜ 5 ⎟ ⎜ 6 −3 ⎟ min ⎝10 M8 ⎠ ⎝10 g cm ⎠ Ultra-long duration requires WD density Krolik & Piran 11 2017/01/24 ultralong GRB & TDE by K. Ioka 2 Magnetar? Greiner+ 15 Ultra-long GRB GRB 130925A Low-Luminosity GRB Magnetar Toma+ 07 Tidal Levan+ 14 Disruption Gendre+ 13 Lien+ 16 Event 2017/01/24 ultralong GRB & TDE by K. Ioka 14 Supernova Component? Even brighter than SN1998bw (hypernova)? Against TDE model? Really supernova? Levan+ 14 2017/01/24 ultralong GRB & TDE by K. Ioka 15 Bright SN 2011kl ~10 days after GRB 111209 GROND multiband X-shooter on VLT Supernova ⇒ TDE × No H line ⇒ BSG × ⇒ Magnetar? Greiner+ 15 2017/01/24 ultralong GRB & TDE by K. Ioka 16 Spectrum X-shooter spectrum − GRB afterglow# " host galaxy Supernova ⇒ TDE $! No H line ⇒ BSG $! ⇒ Magnetar No Ca II, C II lines ⇒ v>2e9 cm/s Greiner+ 15 2017/01/24 ultralong GRB & TDE by K. Ioka 17 SN does not Exclude TDE Half bound Half unbound Super-Eddington ⇒ Disk outflow, γ ⇒ E into Ejecta ⇒ SN-like bump KI, Hotokezaka & Piran 16 2017/01/24 ultralong GRB & TDE by K. Ioka 18 Light Curve Modeling One zone Arnett 79, 82 3 Kasen & Bildsten 10 V ∝ R Dexter & Kasen 13 ∂E ∂V E int p = int = −p + H (t) + L(t) 3V t t ∂ ∂ v = R! L t c ∂ E V c E V ( ) = ( int ) ≈ int 4π R2 3κρ ∂R 3κρ R ! d t $ t Diffusion time # + 2 &L(t) = 2 H (t) " dt td % td t2 3κM − 2 2 t( 2td t = e t 2 d L t = dt( t(e 2td H t( 4πcv ( ) 2 ∫ 0 ( ) td 2017/01/24 ultralong GRB & TDE by K. Ioka 19 SN-like Light Curve Lbol (Greiner+15) ] GM BH (M* 2) -1 L using unbroken afterglow 44 bol E ~ 10 PS1-11af (TDE) 2amin 51 PTF11rks (SLSN) ~ 4 ×10 erg 43 −1 L ~ LEdd ~ 10 erg s 43 ⎛ ⎞ 10 M BH 98bw (SN) ×⎜ 5 ⎟ ⎝10 M8 ⎠ Explosion 52 4 9 -1 Ei=1.4×10 erg, ti=1×10 s, M=3 M , v=2×10 cm s , =0.2 GM BH ⊙ 2 v ~ Magnetar H=(E/te)/(1+t/te) min 50 6 9 -1 E=1.4×10 erg, te=1.1×10 s, M=2.2 M , v=2×10 cm s , =0.04 2amin 42 ⊙ 5/3 Bolometric luminosity [erg s 10 Tidal Disruption Event H=(2E/3te)/(1+t/te) 50 5 9 -1 9 −1 E=2.4×10 erg, te=2×10 s, M=1 M , v=2×10 cm s , =0.2 ~ 2 10 cm s ⊙ × 0 10 20 30 40 50 Rest-frame time after explosion [days] KI, Hotokezaka & Piran 16 2017/01/24 ultralong GRB & TDE by K. Ioka 20 Multi-band Lightcurve 1 18 u 19 g r 20 i z 21 22 Magnetar 2 AB magnitude 23 H=(E/te)/(1+t/te) 50 E=1.4×10 erg 6 24 te=1.1×10 s M=2.2 M 9 ⊙ -1 Caveat 25 v=2×10 cm s =0.04 Ekin >> Einj 26 4 5 6 7 ~0.04 10 10 10 10 κ Observer time after burst trigger [s] 2017/01/24 ultralong GRB & TDE by K. Ioka 21 Multi-band Lightcurve 2 18 u 19 g r 20 i z 21 22 Blue Supergiant AB magnitude 23 52 Ei=1.4×10 erg 4 24 ti=1×10 s M=3 M ⊙9 -1 25 v=2×10 cm s =0.2 Caveat 26 4 5 6 7 10 10 10 10 Ekin >> Einj Observer time after burst trigger [s] 2017/01/24 ultralong GRB & TDE by K. Ioka 22 Multi-band Lightcurve 3 18 u 19 g r Power-law AG 20 i z (Not broken PL) 21 ⇒ Different Lbol 22 Tidal Disruption Event 5/3 AB magnitude 23 H=(2E/3te)/(1+t/te) 50 E=2.4×10 erg 5 24 te=2×10 s M=1 M ⊙9 -1 25 v=2×10 cm s =0.2 26 104 105 106 107 Observer time after burst trigger [s] 2017/01/24 ultralong GRB & TDE by K. Ioka 23 Peculiar Magnetar l Spindown time should be tuned to tpeak# 3 −2 2 # 6Ic 6 $ B ' $ P ' te = ≈ 1.1×10 s& ) & ) # B2 R6Ω2 % 7.5×1014 G ( %12.2ms( >> tGRB See also Cano, Johansson & Maeda 16 l Radiation energy# Bersten+ 16 # 1 E = IΩ2 ≈ 1.3×1050 erg # rot 2 << Kinetic energy Mv2/2 l How to explain GRB? Not simple 2017/01/24 ultralong GRB & TDE by K. Ioka 24 Tidal Disruption Event? • Supernova: might be • GRB timescales ⇒ WD TDE • Energy ⇒ WD has enough mass • Super-Eddington ⇒ Jet • Event rate ~3e-6/yr ⇒ consistent • Light curve L~t-5/3 • Host galaxies 2017/01/24 ultralong GRB & TDE by K. Ioka 25 Host Galaxies • faint, compact, and highly star forming dwarf galaxies, typical of "blue compact galaxies” For WD TDE 6 MBH<10 M¤ M-σ relation 2017/01/24 ultralong GRB & TDE by K.