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arXiv · 1803.08504

AGN mass estimates in large spectroscopic surveys: the effect of host galaxy light

Ludovica Varisco·Tullia Sbarrato·Giorgio Calderone·Massimo Dotti
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Abstract

Virial-based methods for estimating active supermassive black hole masses are now commonly used on extremely large spectroscopic quasar catalogues. Most spectral analyses, though, do not pay enough attention to a detailed continuum decomposition. To understand how this affects virial mass estimate results, we test the influence of host galaxy light on them, along with Balmer continuum component. A detailed fit with the new spectroscopic analysis software QSFit demonstrated that the presence or absence of continuum components do not affect significantly the virial-based results for our sample. Taking or not in consideration a host galaxy component, instead, affects the emission line fitting in a more pronounced way at lower redshifts, where in fact we observe dimmer quasars and more visible host galaxies.

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Ludovica Varisco, Tullia Sbarrato, Giorgio Calderone, Massimo Dotti. 2018-03-22. AGN mass estimates in large spectroscopic surveys: the effect of host galaxy light. https://doi.org/10.1051/0004-6361%2F201832655

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