Accretion rates and accretion efficiency in AGNs
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چکیده
We used the standard geometrical thin accretion theory to obtain the accretion rates in Seyfert 1 galaxies and quasars. Combining accretion rates with the bolometric luminosity, we obtained the accretion efficiency. We found most of Seyfert 1 galaxies and radio quiet quasars have lower accretion efficiencies while most of the radio loud quasars possess higher accretion efficiencies. This finding further implies most of radio loud quasars possess Kerr black holes while Seyfert 1 galaxies and radio quiet quasars may not possess Kerr black holes. Considering the difference of the accretion efficiency we found there is a strong correlation between the accretion rate in units of the Eddington accretion rate and the width of the Hβ emission line and most of AGNs are not accreting at Super-Eddington rates.
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تاریخ انتشار 2003