Study On Radiation Characteristics And Evolution Of Fermi Variant In Multi - Band

Blazars are one of the most extreme classes of active galactic nuclei(AGN),with high luminosity, large amplitude and rapid variability, high and variable polarization, radio coredominance, and apparent super-luminal speeds. The broad band emission extends from radio up to ? ?ray band, being observed almost at the full electromagnetic spectrum from radio to ? ?ray band, and dominated by nonthermal processes. These extreme nature of blazars reflect the structure and physical process are very complicated. The studies of these properties contribute to understand the structure, the evolutionary sequence, the radiation mechanism and other major problems of Fermi blazars. In this thesis, we present the studies of the super black hole mass, the properties of multi-wave band emission, the radiation mechanism of high enengy gamma ray, the relation between jet and accretion, and evolution.In chapter 1, we briefly introduce the basic conception, class and model of active galactic nuclei(AGN), the estimate of black hole mass.In chapter 2, we briefly introduce blazars whose discovery process, the phenomenon of observation and extreme physical properties, classification standards and methods, the properties of multi-wave band emission and spectral characteristics.The radiation mechanism of blazars(the synchrotron radiation, inverse Compton(IC)scattering, leptons models, hadronic models, relativistic jets models), relativistic beaming effects and briefly introduce the Fermi-LAT and Fermi source.In chapter 3, we collect the redshift,between the black hole mass, the radio,infrared, optical, X-ray flux densities(FR, FIR, FO, FX) in low state and restudy the physical properties of HBLs and LBLs. Our conclusions are as follows:(1) the black hole masses distribution of two subclasses(HBLs and LBLs) are quite different;(2)LBLs have high redshift and the evolution of LBLs occur in the earlier phase of the BL Lacs evolutionary sequence;(3) in low state, the correlation between redshift and multi-wave band flux densities, between multi-wave band flux densities suggest that the radiation mechanism of two subclasses are quite different.In chapter 4, Using ? ?ray data detected by Fermi Large Area Telescope(LAT)and multi-wave band data for 35 TeV blazars sample, we have studied the possible correlations between different broad band spectral indices(r,ir? 、r,o? 、r,xa 、r,?? 、ir,o? 、ir,x? 、ir,?? 、0,x? 、o,?? 、x,??) in all states(average/ high/low). Our results are as follows:(1) For our TeV blazars sample, the strong positive correlations were found betweenr,ir? andr,o?, betweenr,ir? andr,xa, betweenr,ir? andr,?? in all states(average/high/low);(2) For our TeV blazars sample, the strong anti-correlations were found betweenr,ir? andx,??, betweenr,o? andir,??, betweenr,o? ando,??,betweenr,o? andx,??, betweenir,o? ando,??, betweenr,xa andx,??, betweenir,x? and x,?? in all states(average/ high/low). The results suggest that the synchrotron self-Compton radiation(SSC) is the main mechanism of high energy ? ?ray emission and the inverse Compton scattering of circum-nuclear dust is likely to be a important complementary mechanism for TeV blazars. Our results also show that the possible correlations vary from state to state in the same pair of indices,Which suggest that there may exist differences in the emitting process and in the location of the emitting region for different states.In chapter 4, Using ? ?ray data(??, F?) detected by Fermi Large Area Telescope(LAT) and black hole mass which has been compiled from literatures for116 Fermi blazars, we calculated intrinsic ? ?ray luminosity, intrinsic bolometric luminosity, intrinsic Eddington ratio and studied the relationships between all above parameters and redshift, between?? and L?. Furthermore, we obtained the histograms of key parameters. Our results are the following:(1) The main reason for the evolutionary sequence of three subclasses(HBLs, LBLs, FSRQs) may be Eddington ratio rather than black hole mass;(2) FSRQs occupy in the earlier, high-luminosity,high Eddington ratio, violent phase of the galactic evolution sequence, while BL Lac objects occur in the low luminosity, low Eddington ratio, late phase of the galactic evolution sequence;(3) These results imply that the evolutionary track of Fermi blazars is FSRQs �' LBLs�' HBLs.