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arXiv · 1212.1181

Black hole mass estimate for a sample of radio-loud narrow-line Seyfert 1 galaxies

G. Calderone·G. Ghisellini·M. Colpi·M. Dotti
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Abstract

We discuss the relationship between a standard Shakura & Sunyaev (1973) accretion disk model and the Big Blue Bump (BBB) observed in Type 1 AGN, and propose a new method to estimate black hole masses. We apply this method to a sample of 23 radio-loud narrow-line Seyfert 1 (RL-NLS1) galaxies, using data from WISE (Wide-field Infrared Survey Explorer), SDSS (Sloan Digital Sky Survey) and GALEX. Our black hole mass estimates are at least a factor $\sim$6 above previous results based on single epoch virial methods, while the Eddington ratios are correspondingly lower. Hence, the black hole masses of RL-NLS1 galaxies are typically above $10^8 M_{\sun}$, in agreement with the typical black hole mass of blazars.

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G. Calderone, G. Ghisellini, M. Colpi, M. Dotti. 2012-12-05. Black hole mass estimate for a sample of radio-loud narrow-line Seyfert 1 galaxies. https://doi.org/10.1093/mnras%2Fstt157

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