Bolometric correction factors for active galactic nuclei

Abstract

ABSTRACT The bolometric luminosity of active galactic nuclei (AGNs) is difficult to determine, and various approximations have been used to calibrate it against different observed properties. Here, I combine theoretical calculations of optically thick, geometrically thin accretion discs, and observed X-ray properties of AGN, to provide new bolometric correction factors (kBOL) over a large range of black hole (BH) mass, accretion rate, and spin. This is particularly important in cases where the mass accretion rate cannot be determined from the observed spectral energy distribution, and in cases where luminosity-independent correction factors have been used. Simple power-law approximations of kBOL are provided for L(5100 Å), L(3000 Å), L(1400 Å), L(2–10 keV), and L(narrow Hβ). In all cases, the uncertainties are large mostly due to the unknown BH spin. Prior knowledge of the BH mass reduces the uncertainty considerably.