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arXiv · 1712.07250

Luminous and obscured quasars and their host galaxies

Agnese Del Moro·David M. Alexander·Franz E. Bauer·Emanuele Daddi·Dale D. Kocevski·Flora Stanley·Daniel H. McIntosh
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Abstract

The most heavily-obscured, luminous quasars might represent a specific phase of the evolution of actively accreting supermassive black holes and their host galaxies, possibly related to mergers. We investigated a sample of the most luminous quasars at $z\approx 1-3$ in the GOODS fields, selected in the mid-infrared band through detailed spectral energy distribution (SED) decomposition. The vast majority of these quasars (~80%) are obscured in the X-ray band and ~30% of them to such an extent, that they are undetected in some of the deepest (2 and 4 Ms) Chandra X-ray data. Although no clear relation is found between the star-formation rate of the host galaxies and the X-ray obscuration, we find a higher incidence of heavily-obscured quasars in disturbed/merging galaxies compared to the unobscured ones, thus possibly representing an earlier stage of evolution, after which the system is relaxing and becoming unobscured.

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Agnese Del Moro, David M. Alexander, Franz E. Bauer, Emanuele Daddi, Dale D. Kocevski, Flora Stanley, Daniel H. McIntosh. 2017-12-19. Luminous and obscured quasars and their host galaxies. https://arxiv.org/abs/1712.07250

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