The Emission Mechanism Of Jet Fromt The Gamma-Ray Bursts And Blazars

This thises briefly introduces the observational and theoretical progress of gamma-ray bursts(GRBs) and active galaxies nuclei (AGNs), and then reports our analysis results of the comparision between the spectral properties of GRBs and AGNs.The GRB spectra generally can be empirically fitted with a smoothly jointed broken power-law function (the Band function). Its radiation mechanism is still unknown. We derive the mono-frequency peak luminosity and the corresponding photon energy of the time-integrated (Lps,Eps) and peak time (Lp1,Epl) of vFv spectra for a sample of38redshift-known Fermi GRBs until the Apiril2014by fitting the spectra with the Band function. It is found that Epl is generally consistent with Eps, and Lpt is averagely three times larger than Lps. The slope of the Lpt-Ept relation is consistent with that of the Lps-Eps relation with the error bars. The photon indices in the peak time spectrum, especially the index of the low energy end, are statistically larger than that in the time-integrated spectrum. These results indicate that Eps are dominated by Ept. The difference of the spectral indices between the time-integrated and peak time spectra may be due to the overlap effect of a series of time-resolved spectra within a GRB. Our simulations, which are based on the observed spectral evolution and correlation between the energy flux and the peak energy within individual GRBs support our speculations. The Lpt-Ept relation may be less contaminated by the overlap effect, and it would be an intrinsic feature of the radiation physics. Based on our above spectral anlaysis results, we compare the distributions of the GRBs and the blazars by plotting their synchrotron peak luminosity (Ls) and the corresponding peak photon energy Es of blazars in the EP-LP plane of GRBs, where Lp and EP are the peak luminosity and the peak photon energy of the GRB time-integrated vFv spectrum, respectively. The GRBs are in the high-p, high-Epcorner of the plane and a tight EP-LP relation is found, i.e.,Lp∝EP1.52±0.20. Both FSRQs and LBLs are clustered in the low-EP, low-LP corner and a weak trend in which sources with higher Ls tend to have a lower Es. IBLs and HBLs range in Es～2×10-3-102keV and Ls～1044-1047ergs-1, but no any dependence of Ls on Es is found. We investigate the possible implications for the radiation physics and show that the tight LP-EP relation of GRBs is potentially explained with the synchrotron radiation of fast-cooling electrons in the highly magnetized ejecta, and the weak anti-correlation of Ls-Es for FSRQs and LBLs may be attributed to synchrotron radiation of slow-cooling electrons in a moderately magnetized ejecta. On the other hand, the distributions of IBLs and HBLs in the LP-EP plane are likely interpreted with the synchrotron radiation of fast-cooling electrons in the matter-dominated ejecta. These results may present a unified picture for the radiation physics of the relativistic jets in GRBs and blazars in the framework of the lepton synchrotron radiation model.