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Complex Broad Emission Line Profiles of AGN - Geometry of the Broad Line Region

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 نشر من قبل Edi Bon
 تاريخ النشر 2009
  مجال البحث فيزياء
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The Broad Emission Lines (BELs) in spectra of type 1 Active Galactic Nuclei (AGN) can be very complex, indicating a complex Broad Line Region (BLR) geometry. According to the standard unification model one can expect an accretion disk around a supermassive black hole in all AGN. Therefore, a disk geometry is expected in the BLR. However, a small fraction of BELs show double-peaked profiles which indicate the disk geometry. Here, we discuss a two-component model, assuming an emission from the accretion disk and one additional emission from surrounding region. We compared the modeled BELs with observed ones (mostly broad H$alpha$ and H$beta$ profiles) finding that the model can well describe single-peaked and double-peaked observed broad line profiles.



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