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Hadronic cascades in GRBs and AGNs Katsuaki Asano (Tokyo Tech.) Collaboration with S.Inoue, P.Meszaros M.Kino GRB Standard Picture Internal Shock External Shock ISM GRB Short GRB Precursor Delay z=0.903 E iso =10 53 erg 8keV-260keV 260keV-5MeV >100MeV >1GeV 31GeV, 3.4GeV GRB ; Spectra Band+ Extra PL GRB B E iso =4x10 54 z=1.822 Abdo et al. ApJ 706, L138 Extra Component in B Extra Component=Afterglow? GRB Monte-Carlo Method R R=R/ 2 Photons: Luminosity L Power-law injection of protons Energy density of photons U Energy density of magnetic field U B =f B U Energy density of Accelerated protons U p =f p U Method t . dt Emission (Synch. IC) p Yes or No? Yes -> + or 0 Proton Neutron Proton + - 0 Cross Sections n + processes also Inelasticity Iterative Method To estimate p, Inv.Comp., processes, we need a photon field. During the dynamical timescale, the photon field is assumed to be steady. Photon Field By hand Calculation Photon Field Result Calculation Photon Field Result Cascade Processes n+ + + e + + e p+ 0 0 + p + e - + e + e - + e + Synchrotron + Inv.Comp.: p, , ,e Synchrotron Self-absorption: e e Iterative Method -> Both photon field and cascade processes are solved consistently. Highest Energy The Larmor radius R L =e E p /B < shell width =R/. The acceleration time R L /c < cooling time. The energy of particles is limited by two conditons. Cooling Processes: Proton Synchrotron+IC Photoproduction of pions Bethe-Heitler Proton acceleration efficiency We need ergs/Mpc 3 /yr to explain UHECRs See e.g. Murase, Ioka, Nagataki, Nakamura 2008 We may need Up/U>20. If GRB rate is 0.05 Gpc -3 /yr, Up/U>100 Proton Dominated? Energy Gamma keV Proton E -2.0 PeV-EeV E 2 n(E) To make gamma-rays from protons contribute enough, the proton energy largely exceeds the gamma-ray energy?? Efficent for pion production Distortion due to proton cascade Lepton distribution E Primary Electrons Pairs from Cascade f B =1.0 e-SY Up=U Double break f B =1.0 e-SY Double break 2 Much More Protons Primary Electron Components Energy-dependence B-dependence GRB ; Spectra Band+ Extra PL Cascade due to photopion production 3.4GeV R=10 14 cm =1500 Synchrotron and Inverse Compton due to secondary electron-positron pairs Band component -absorption Asano, Guiriec & Meszaros 2009 The maximum energy is determined by the dynamical timescale. A long cooling timescale -> low efficiency of pion- production The cooling timescales (comoving frame) of protons due to synchrotron, inverse Compton, Bethe-Heitler, and photopion production are plotted. The dynamical timescale is R/ c. Proton Synchrotron R=10 14 cm Even in this case, secondary pairs contribute Proton synchrotron case Synchrotron is the most efficient in this case. We suppress E max to avoid too much secondary photons. t acc =R L /c Neutrinos from GRB We may need >10 -2 erg/cm 2 to detect with IceCube. Bright Neutrino GRB B Hadronic Model s =-0.07, =-3.9 Photosperic? Naked Eye GRB GRB080319B Hadronic In preparation E iso erg GRBs GeV Photon detection -> >1000 Extra Component -> Afterglow? Hadronic? High -> Lower Photon Density, Magnetic Field ->Lower Effciency for Photopion Production Hadronic Models require >10 55 erg/s for GRB Ref. E iso erg in gamma-rays for GRB080916C Gamma-rays from hypernovae Soderberg et al. 2006 Particle Acceleration in Winds Relativistic component 1, E k erg Proton Cooling in Hypernova A*=5 Secondary Photons Muon-Decay Origin Absorbed Proton SY Origin Hypernovae Secondary emission from hyeprnovae X-ray due to cascade from muon decay GeV emission from proton synchrotron Delayed TeV emission HN Rate 500 Gpc -3 yr -1 Compact Radio-Loud AGN CSOs (Compact symmetric objects ) Radio lobe nuclei 3C 84 ~10 pc Size < 500 pc 120 kpc FRII radio galaxies Evolution?? e.g., Carvalho et al. 1985; Fanti et al. 1995; Begelman 1996; Readhead et al. 1996, Velocity of Hot Spot: 0.1 c for 20 CSOs CORALZ(COmpact RA-dio sources at Low-Redshift): erg/s HFPs(high frequency peakers): erg/s Gamma-Rays from Compact Radio AGNs Core of Seyfart 2 gal. NGC 1275 (M BH =3*10 8 M sun ) z= Other radio bubbles (Pedler+91, Vermeulen+96) Asada+06 5 pc VSOP view of 3C84 Chandra view of Perseus Cluster (Fabian) 3C84 (NGC1275) Fermi (>200MeV) SSC Model EGRET Fermi UMRAO Abdo+09 COS-B Long Term Evolution Nagai+09, submitted Born! app = 0.23 Lobe Generation VERA Nagai+09, submitted freq. dependent? (need further studies) Lobe Velocity Nagai+09, submitted Smoking-gun of core-outburst Wide-view (~kpc) Core (~pc) Radio Light Curve Hadronic Model for Compact Radio AGNs 2pc 10pc UV: L=3x10 45 erg/s, T=10eV Disk Proton Injection L=5x10 46 erg/s Adiabatic Expansion v exp =0.1c B=0.1G Spectrum UV D=100Mpc Hadronic Contributions SED of mini radio-lobe (t_age=t_inj) Kino & Asano in prep VLBI obs. Stars/Dusts overlapped ICM/ Hot-disk overlapped With/Without protons is distinguishable at domain! SNR(?) Case Electron Injection has been already stopped? Pure Hadronic Case


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