Testing the Evolutionary Link Between SMGs and QSOs: are Submm-Detected QSOs at z~2 `Transition Objects' Between These Two Phases?

TL;DR

This paper investigates whether submm-detected QSOs at z~2 are transitional objects linking SMGs and QSOs, by analyzing black hole masses and molecular gas properties to understand galaxy evolution.

Contribution

It provides observational evidence supporting the evolutionary link between SMGs and QSOs through black hole and gas mass measurements.

Findings

Submm-detected QSOs have black hole masses consistent with being transition objects.

CO observations suggest similar gas properties between QSOs and SMGs.

Results support a galaxy evolution sequence from SMGs to QSOs.

Abstract

Local spheroids show a relation between their masses and those of the super-massive black holes (SMBH) at their centres, indicating a link between the major phases of spheroid growth and nuclear accretion. These phases may correspond to high-z submillimetre galaxies (SMGs) and QSOs, separate populations with surprisingly similar redshift distributions which may both be phases in the life cycle of individual galaxies, with SMGs evolving into QSOs. Here we briefly discuss our recent results in Coppin et al. (2008), where we have tested this connection by weighing the black holes and mapping CO in submm-detected QSOs, which may be transition objects between the two phases, and comparing their baryonic, dynamical and Halpha-derived SMBH masses to those of SMGs at the same epoch. [abridged]