Study On The Physical Properties Of Blazar Jet

The central core area of the active galactic nucleus(AGN)is a supermassive black hole,and studying AGN can further understand black holes.Blazar is the most extreme and powerful subclass of AGN,and it has become one of the key sub-categories of AGN research.Chapter 1 of this article mainly introduces the observation characteristics,unified model and classification of AGN and blazar.Chapter 2 introduces the characteristics and functions of the spectral energy distribution(SED)and the light curve obtained from the observation of the blazar jet.In Chapter 3,we introduce the jet model to explain the two bumps of SED,including the synchrotron radiation process and IC process under the lepton model,and the hadron model.The particle acceleration mechanism of the jet and the location of the gamma-ray radiation regions have not yet been determined,so these two points are also the focus of researchers.Therefore,Chapter 4 introduces the principles of different particle acceleration mechanisms of jets.Chapter 5 introduces the significance of studying the location of the radiation regines of the jet and several methods to determine the location of the radiation regines.Chapter 6,by fitting 60(quasi-)simultaneous SEDs of Fermi-4 LAC FSRQ,the physical properties such as the particle acceleration mechanism and the location of the dissipation regines are studied.The main results arere:(1)There is a linear correlation between synchrotron peak frequency and curvature of the electron energy distribution.As suggested by previous works,the slope of the best linear fitting equation of this correlation is consistent with statistic acceleration that needs a fluctuation of fractional acceleration gain.(2)The ?-ray dissipation regions are located at the range from 0.1 to 10 pc away from the supermassive black hole,and located outside the broad-line region and within the dusty torus.(3)A size relation P_e?P_B?P_r<P_p,P_e?P_B suggests that SEDs of almost all FSRQs with parameters are close to equipartition between the magnetic field and the relativistic electrons.The P_e ? P_r suggest that the most energy of the relativistic electrons are dissipated by EC radiation for FSRQs.(4)There is an anticorrelation between the peak energy of SEDs ypeak and the jet power (P_jet),which is consistent with the blazar sequence.