| 其他摘要 | Since 1940s the AGN have been found, it is one of the most popular field in astrophysics for its violent variability, high lunminosity, high redshift and other extreme characteristics, high efficient produce energy, radiation mechanism, distribution in space and extreme condition become one of the most popular researching field in astrophysics field. The research about these problem will help to imply the origin,configuration and evolvement of AGN. Blazar is asubclass of AGN.According to unified model,it is a kind of AGN which the angle between the jet and the line of our sight is very small. Usually, its high luminosity, rapid variability and superluminal motion are come from relativistic jet, so the researching about blazar means the research about the jet, Through the researching about blazar and the other radio loud AGN is useful to solve the problem that jet obtain energy from the black hole and accretion system. Since the Compton Gamma-Ray Observatory was launched successfully in 1990s, It had opened a new researching field. It had detected 66 blazars with high confidence and 27 possible blazars. Their SED usually have "two bumps", The peak of low energy is usually considered as synchrotron radiation of the relativistic electron, and the peak of high energy usually considered as synchrotron-self-compton, external compton radiation whose seed photons may be come from accretion disk, broad line region, torus and so on. It also may be produced by hadron, there are no conclusion from now on. The second gamma-ray telescope-GLAST will be launched in August this year, Its detected capability is higher than EGRET, may have breakthrough greatly in blazar field. So there may have great prospect in the next tens years. There are four chapters in this thesis, Chapter one introduce the fundamental characteristics and the classification of AGN, and introduce the history of unified model and researching situation about unified model; The chapter two mainly introduce some famous samples of blazar survey and relativistic jet model,and some characteristics of relativistic jet; Chapter three present the spectral energy distribution of blazar in multi-band and the explanation of high energy radiation model, and introduce two special blazar - MeV blazar and GeV blazar simply; Chapter four is our work which has been accepted recently. The emission radiation of EGRET objects is a very popular field, but EGRET did not detect the radiation of some famous objects (eg: 3C 345). It suggests the emission radiation of GeV/MeV blazar from other aspects by compare and analysis the EGRET blazar and non-EGRET blazar. Our work is mainly compares and analysis the variability amplitude,the shortest variability timescale and time delay among 3C 345,3C 273 and 3C 279.We find the the SED of 3C 345 in gamma-ray band may be similar with 3C 273, that means the peak of gamma-ray SED is mainly in MeV energy, and the spectrum in GeV energy band is much steeper, May be EGRET did not detect 3C 345 by this reason. |
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