Seyferts and Radio Galaxies
نویسندگان
چکیده
Observations with Compton Gamma Ray Observatory have provided key insights to the high energy emission mechanisms in Active Galactic Nuclei (AGN) and clearly separate them into a class of Blazars, with apparent non-thermal jet emissions often peaking in the EGRET energy band, and into the Seyfert class with emissions more closely related to the accretion disk presumably energizing the nuclear black hole. OSSE measurements indicate that the high energy emission from Seyfert AGN has a high energy cutoo below 100 ? 200 keV and no Seyferts have been detected by COMPTEL or EGRET. Here, we review the X-ray and-ray observations of Seyferts and Radio Galaxies and the broad band emission models that describe the observed spectral characteristics. A compari-sion of Seyfert 1, Seyfert 2, and radio galaxies can be made in the context of the AGN uniication models.
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تاریخ انتشار 2007