| Description |
The coevolution of central black holes (BH) and their host galaxies driven by starbursts and the feedback of AGN are major elements of recent galaxy evolution models. Here we propose to investigate these processes in a volume limited sample of PG QSOs, by examining if and how their ISM properties reflect the evolutionary stages of the host galaxy, and the mass of the central black holes. PG QSOs are ideal for such a study because there are complete and uniform data on their BH masses, X-ray to MIR SEDs, NIR and MIR spectral characteristics as well as HST imaging. As such their accretion rates are well known. Here, we request 43.2 hours of PACS and SPIRE observations to measure the full FIR SEDs for a complete sample of 87 PG-QSOs. These data will provide unique sampling of the ISM content of the hosts with measurements of the dust masses, luminosities and temperatures. For objects at the mean redshift of z = 0.2, the proposed PACS photometry will be used to constrain the mass of hot (virgul60 K) and cold (virgul25K) dust down to 3e5 and 3e7 Solar Masses respectively, that is total ISM masses similar or less than the Milky Way. As such the proposed data will provide extremely impressive measurements of (1) the ISM masses and luminosities present in the PG-QSO hosts and (2) the relative amounts of gas in high activity (hot dust -- star-formation or AGN) versus low radiation field environments. These datawill provide the fundamental dataset for studies of the IR radiation from optical QSOs and understanding the host galaxy properties. The goals of this proposal mesh well with one of Herschel.s main mission statements: Unveiling hidden details of star and galaxy formation and evolution. |
