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arXiv · 1811.10644

The infrared-luminous progenitors of high-z quasars

Michele Ginolfi·Raffaella Schneider·Rosa Valiante·Edwige Pezzulli·Luca Graziani·Seiji Fujimoto·Roberto Maiolino
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Abstract

Here we explore the infrared (IR) properties of the progenitors of high-z quasar host galaxies. Adopting the cosmological, data constrained semi-analytic model GAMETE/QSOdust, we simulate several independent merger histories of a luminous quasar at z ~ 6, following black hole growth and baryonic evolution in all its progenitor galaxies. We find that a fraction of progenitor galaxies (about 0.4 objects per single luminous quasar) at 6.5 < z < 8 has an IR luminosity of L_IR > 10^13 Lsun (hyper-luminous IR galaxies; HyLIRGs). HyLIRGs progenitors reside in the most massive halos, with dark matter (DM) masses of M_DM ~ 10^12.5 - 10^13 Msun. These systems can be easily observed in their ~ 1 mm-continuum emission in a few seconds of integration time with the Atacama Large Millimeter/submillimeter Array (ALMA), and at least 40% of them host nuclear BH activity that is potentially observable in the soft and hard X-ray band. Our findings are in line with recent observations of exceptional massive DM halos hosting HyLIRGs at z ~ 7, suggesting that z ~ 6 luminous quasars are indeed the signposts of these observed rare peaks in the high-z cosmic density field, and that massive IR-luminous galaxies at higher z are their natural ancestors.

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Michele Ginolfi, Raffaella Schneider, Rosa Valiante, Edwige Pezzulli, Luca Graziani, Seiji Fujimoto, Roberto Maiolino. 2018-11-26. The infrared-luminous progenitors of high-z quasars. https://doi.org/10.1093/mnras%2Fsty3205

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