Observational Study On Blazars Variability And Seeing

Large amplitude and rapid variability, high polarization, broad band nonther-mal radiation energy spectrum are the main characteristics of the blazars. The research of variability of blazars has alaways served as an effective way for con-straining the physics of these objects. In the thesis, we review the observational properties and theoretical studies on variability of blazars. We study the short timescale variability and the influence of seeing to variability by using the optical monitoring of blazars in2012with1m telescope of Yunnan observatory.We have performed a campaign for3C273, Mrk501, OJ287,3C454.3, PKS0716+714and3C66A observation in2012. During our observation campaign, magnitude change of3C273in each band is in a very quiet state. The variation trends of Mrk501in each band are different. The maximum magnitude change is in B band with△B=14.926(0.017)-14.609(0.024)=0.317, while the minimum magnitude change is in I band with AI=13.002(0.014)-12.689(0.044)=0.066. OJ287has similar variation trends in three observation bands. The overall mag-nitude variations of the source OJ287are AI=13.448(0.048)-13.174(0.030)=0.274,△R=14.013(0.022)-13.778(0.042)=0.235and AV=14.381(0.022)-14.105(0.036)=0.276.3C454.3is in a state of active, there are variabilities in BVRI bands. The variability parameters are C=3.862,C=5.418,C=8.455and C=5.876respectively. For blazars PKS0716+714and3C66A, we don’t observe the variability.We study the influence of the seeing to variability. Although the atmospheric seeing varied in a large scale from night to night, there is no evidence in correlation of atmospheric seeing and variability. This means that the variability don’t depend on seeing changes.