Gammaray Bursts and Particle Acceleration Katsuaki Asano Tokyo

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Gamma-ray Bursts and Particle Acceleration Katsuaki Asano (Tokyo Institute of Technology) S. Inoue(NAOJ), P.

Gamma-ray Bursts and Particle Acceleration Katsuaki Asano (Tokyo Institute of Technology) S. Inoue(NAOJ), P. Meszaros(PSU)

Physical Condition in a Shell ΔR=R/Γ 2 R Photons: Luminosity L In the comoving

Physical Condition in a Shell ΔR=R/Γ 2 R Photons: Luminosity L In the comoving frame Energy Density: Magnetic Field:

Time Scales Let us consider a proton of 1019 e. V In the comoving

Time Scales Let us consider a proton of 1019 e. V In the comoving frame, Acceleration Time Scale: Dynamical Time Scale: Cooling Time Scale:

How to find evidence of proton acceleration?

How to find evidence of proton acceleration?

Neutrinos

Neutrinos

Neutrinos p+γ→n+π+ π+→μ+ +νμ 5 4 μ+ →e+ + νμ + νe Muon-decay log[E

Neutrinos p+γ→n+π+ π+→μ+ +νμ 5 4 μ+ →e+ + νμ + νe Muon-decay log[E N(E)] 2 0 -1 -2 -3 -4 4 Next talk -> Murase 3 Pion-decay 3 1 5 2 1052 erg x 100 G=500 R=5 1014 cm e. B=0. 1 ee at 1 Gpc by 105 km 2 detector Kaon-decay 1 0 Waxman and bahcall 1997, 1998 -1 -2 -3 Asano & Nagataki 2006 -4

Photons See e. g. Meszaros 2006, Dermer & Atoyan 2006

Photons See e. g. Meszaros 2006, Dermer & Atoyan 2006

GRB spectrum ? ? ?

GRB spectrum ? ? ?

To catch the sign of proton acceleration • GLAST will be Launched May in

To catch the sign of proton acceleration • GLAST will be Launched May in this year. • It will observe 10 Me. V - 300 Ge. V photons.

Te. V Photons CANGAROO-III MAGIC HESS

Te. V Photons CANGAROO-III MAGIC HESS

Proton Cascade p+γ→n+π+       →p+π0 Asano 2005

Proton Cascade p+γ→n+π+       →p+π0 Asano 2005

Our Monte Carlo Simulation Distortion due to proton cascade Lepton distribution f. B=1. 0

Our Monte Carlo Simulation Distortion due to proton cascade Lepton distribution f. B=1. 0 Primary Electrons Pairs from Cascade E e-SY Up=Ue f. B=UB/Ue Asano & Inoue 2007

Deviation due to Inv. Comp. f. B=0. 1 e-SY No sign of proton acceleration

Deviation due to Inv. Comp. f. B=0. 1 e-SY No sign of proton acceleration Asano & Inoue 2007

Double break f. B=1. 0 Characteristic Spectrum due to Protons e-SY

Double break f. B=1. 0 Characteristic Spectrum due to Protons e-SY

Proton and muon synchrotron f. B=30. 0 e-SY

Proton and muon synchrotron f. B=30. 0 e-SY

Proton acceleration efficiency We have assumed Up=Ue so far, but… We need 6 -8

Proton acceleration efficiency We have assumed Up=Ue so far, but… We need 6 -8 1043 ergs/Mpc 3/yr to explain UHECRs See e. g. Murase, Ioka, Nagataki, Nakamura 2008 We may need Up/Ue>20. If GRB rate is 0. 05 Gpc-3/yr, Up/Ue>100

GRB rate

GRB rate

Much more protons are accelerated? Acceleration Just behind the shock front Larmor radius∝E

Much more protons are accelerated? Acceleration Just behind the shock front Larmor radius∝E

Much more protons Proton=10 x Electron Asano, Inoue, & Meszaros in prep.

Much more protons Proton=10 x Electron Asano, Inoue, & Meszaros in prep.

Much more protons Proton=100 x Electron Photons from Proton cascade dominate. See also Asano

Much more protons Proton=100 x Electron Photons from Proton cascade dominate. See also Asano & Takahara 2003

Very Hard GRB Kaneko et al. 2008 GLAST will find more such bursts?

Very Hard GRB Kaneko et al. 2008 GLAST will find more such bursts?

Esh-dependence

Esh-dependence

Up-dependence

Up-dependence

Γ-dependence

Γ-dependence

Hypernova • Very bright supernova • Some associate GRBs • Progenitors may be massive

Hypernova • Very bright supernova • Some associate GRBs • Progenitors may be massive stars (WR type? ). • A stellar wind environment may exist around progenitors Ejecta from hypernovae may be sources of 1017 -1018 e. V CRs. (Wang et al. 2007)

Hypernovae are Sources of 1018 e. V Cosmic Rays? SNR? ?? AGN? GRB? 銀河団?

Hypernovae are Sources of 1018 e. V Cosmic Rays? SNR? ?? AGN? GRB? 銀河団? Wang et al. 2007 1020 e. V

Particle Acceleration in Winds Faster, Energetically lower

Particle Acceleration in Winds Faster, Energetically lower

Secondary Particles Asano & Meszaros 2008 @100 Mpc ~ 4 days integration

Secondary Particles Asano & Meszaros 2008 @100 Mpc ~ 4 days integration

Secondary Photons ~ 4 days integration

Secondary Photons ~ 4 days integration

Regenerated Photons GRB Gamma-ray Inv. Comp. e+ e- IR background photons CMB photons Razzaque

Regenerated Photons GRB Gamma-ray Inv. Comp. e+ e- IR background photons CMB photons Razzaque et al. 2004

Summary • Ge. V-Te. V emissions due to protons in GRBs • Too much

Summary • Ge. V-Te. V emissions due to protons in GRBs • Too much protons change spectra drastically • Secondary emission from hyeprnovae – X-ray due to cascade from muon decay – Ge. V emission from proton synchrotron – “Delayed” Te. V emission