Study On The Physical Properties Of Light Variation Of The Flat-spectrum Radio Quasar 3C 279

Active galactic nuclei（AGNs）have become the focus of astrophysics research because of the intense activity and physical process in their nuclei.Blazars,one of the most extreme observational subclasses of AGNs,have rapid and violent light variability.The spectrum energy distribution（SED）has a typical two-component structure.By collecting the blazar multi-waveband quasi-simultaneous/simultaneous observation data and fitting the SEDs,It can perform statistical studies on extrinsic observations and intrinsic physical properties of blazar variability.The first four chapters of this paper are mainly about the basic overview of AGN and blazar,the basic physical process of blazar and the several mechanisms of variation.Finally in the fifth chapter is my own study work.By fitting the data of quasi-simultaneous/synchronous spectral energy distribution of 3C 279,the mechanism of variation and the location of radiation region of 3C 279 are studied.The main results are（1）By comparing the distribution of the electron energy spectrum index,our results show that the cause of the light variation may be shock wave（but requires oblique shock wave）or magnetic reconnection mechanism;The linear relationship between the peak luminosity logarithm log_EC^pk_EC^pkof the external Compton peak and the magnetic field logarithm logis inversely correlated;The linear relationship between the logarithm of the Doppler factor logand the logarithm log_EC^pk_EC^pkof the peak luminosity of the external Compton peak is positive.（2）There is no significant linear relationship between the logarithm log_syn^pkof peak frequency and the logarithm log_syn^pk_syn^pkof peak luminosity.（3）Through the analysis of parameters_and_,it is found that there is no equipartition trend between them,and most jets in 3C 279 are dominated by particles;From the analysis of the relationship among_,,and_,it is found that the energy in the jet3C 279 is carried by cold protons;At the same time,our results show that the gamma-ray dissipation region in 3C 279 is located outside the broad-line region and inside the dust.