Updating quasar bolometric luminosity corrections

Abstract

Bolometric corrections are used in quasar studies to quantify total energy output based on a measurement of a monochromatic luminosity. First, we enumerate and discuss the practical difficulties of determining such corrections, then we present bolometric luminosities between 1 \mu m and 8 keV rest frame and corrections derived from the detailed spectral energy distributions of 63 bright quasars of low to moderate redshift (z = 0.03-1.4). Exploring several mathematical fittings, we provide practical bolometric corrections of the forms L_iso=\zeta \lambda L_{\lambda} and log(L_iso)=A+B log(\lambda L_{\lambda}) for \lambda= 1450, 3000, and 5100 \AA, where L_iso is the bolometric luminosity calculated under the assumption of isotropy. The significant scatter in the 5100 \AA\ bolometric correction can be reduced by adding a first order correction using the optical slope, \alpha_\lambda,opt. We recommend an adjustment to the bolometric correction to account for viewing angle and the anisotropic emission expected from accretion discs. For optical/UV monochromatic luminosities, radio-loud and radio-quiet bolometric corrections are consistent within 95% confidence intervals so we do not make separate radio-loud and radio-quiet corrections. In addition, we provide several bolometric corrections to the 2-10 keV X-ray luminosity, which are shown to have very large scatter. Separate radio-loud and radio-quiet corrections are warranted by the X-ray data.Comment: 18 pages, 5 tables, 12 figures, accepted to MNRA

The cosmic growth of the active black hole population at 1 <z <2 in zCOSMOS, VVDS and SDSS

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Galactic-scale Feedback Observed in the 3C 298 Quasar Host Galaxy

“…- (Runnoe et al 2012). Comparing the outflow momentum flux to the quasar radiation momentum flux (L c bol ) of 3.5 10 36 dynes yields a ratio P P outflow quasaṙ˙( loading factor) of 6.…”

Herschel-ATLAS: the connection between star formation and AGN activity in radio-loud and radio-quiet active galaxies

“…We calculated the ratio of radio luminosity (at 1.4 GHz) to an estimate of optical luminosity (at 5100Å). As our AGN are mostly Type II Seyferts, we do not know their intrinsic optical luminosities and to derive these we used our bolometric luminosities (L bol , see Section 2.4) and the relation between L bol and L5100 given by Runnoe et al (2012). We have 1.4 GHz fluxes of the radio-loud sources from BH12.…”

“…5-GHz radio flux densities were extrapolated assuming a spectral index 0.8. In the same way, we used the relations given by Runnoe et al (2012) between L bol and L5100, and L bol and L3000 to estimate fluxes at 5100Å and at 3000Å, respectively. Considering our sources are at low redshift these values will be approximately equal to the fluxes at 4400Å and 2500Å.…”