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تسجيل مستخدم جديدSupermassive Black Hole Masses in Type II Active Galactic Nuclei with Polarimetric Broad Emission Lines
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Shi-Yan Zhang
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Type II AGNs with polarimetric broad emission line provided strong evidence for the orientation-based unified model for AGNs. We want to investigate whether the polarimetric broad emission line in type II AGNs can be used to calculate their central supermassive black hole (SMBH) masses, like that for type I AGNs. We collected 12 type II AGNs with polarimetric broad emission line width from the literatures, and calculated their central black hole masses from the polarimetric broad line width and the isotropic oiii luminosity. We also calculate the mass from stellar velocity dispersion, $sigma_*$, with the $mbh-sigma_*$ relation.We find that: (1) the black hole masses derived from the polarimetric broad line width is averagely larger than that from the $mbh- sigma_*$ relation by about 0.6 dex, (2) If these type II AGNs follow $mbh-sigma_*$ relation, we find that the random velocity cant not be omitted and is comparable with the BLRs Keplerian velocity. It is consistent with the scenery of large outflow from the accretion disk suggested by Yong et al.
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