Observations with the SPIRE FTS of the ULIRG-QSO Mrk231 have shownthat the CO rotational ladder can be used to separate the contributionof Photon-Dominated Regions (PDRs), powered by star formation, fromthat of X-ray-Dominated Regions (XDRs), powered by the AGN.We propose to apply this diagnostic to a sample of 5 low-z QSOs withdetections in CO, in order to:(1) derive size, density, column density and X-ray illumination of thecircumnuclear medium;(2) measure radiative feedback and derive radiation pressure by theAGN on the surrounding medium, in order to probe its ability to drivethe recently discovered molecular outflows and disperse the nuclear gas,and to assess its importance for the dynamical support of thecircumnuclear medium, which will affect dynamical black hole massmeasurements;(3) determine the importance of star formation in the host galaxy forthe observed infrared luminosity.Our observations consist of SPIRE-FTS spectra of 5 QSOs, and PACSspectra to measure the higher CO lines in the brightest object only.These observations will address the evolutionary relation between QSOsand ULIRGs and the role of QSOs as drivers for the transition betweenactively star forming and passive galaxies. They will also constitutea low-z benchmark for future CO observations of high-z QSOs with ALMA,which can only be provided by Herschel, and which is not covered inthe current Herschel programme.
Publication
On the far-infrared metallicity diagnostics: applications to high-redshift galaxies | Rigopoulou D. et al. | Monthly Notices of the Royal Astronomical Society Volume 473 Issue 1 p.20-29 | 473 | 10.1093\\/mnras\\/stx2311 | 2018MNRAS.473...20R | http://adsabs.harvard.edu/abs/2018MNRAS.473...20R
The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder - II. Estimating radial velocity of SPIRE spectral observation sources | Scott Jeremy P. et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2020MNRAS.496.4894S |
The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder - III. Line identification and off-axis spectra | Benson Chris S. et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2020MNRAS.496.4906B |
Stacked Average Far-infrared Spectrum of Dusty Star-forming Galaxies from the Herschel/SPIRE Fourier Transform Spectrometer | Wilson Derek et al. | The Astrophysical Journal Volume 848 Issue 1 article id. 30 31 pp. (2017). | 848 | 10.3847\\/1538-4357\\/aa8cc7 | 2017ApJ...848...30W | http://adsabs.harvard.edu/abs/2017ApJ...848...30W
L.CO/LFIR Relations with CO Rotational Ladders of Galaxies Across the Herschel SPIRE Archive | Kamenetzky J. et al. | The Astrophysical Journal Volume 829 Issue 2 article id. 93 16 pp. (2016). | 829 | 10.3847\\/0004-637X\\/829\\/2\\/93 | 2016ApJ...829...93K | http://adsabs.harvard.edu/abs/2016ApJ...829...93K
The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder I. The Spectral Feature Finder and Catalogue | Hopwood R. et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2020MNRAS.496.4874H |
AGN impact on the molecular gas in galactic centres as probed by CO lines | Esposito Federico et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2022MNRAS.512..686E |
Herschel was launched on 14 May 2009! It is the fourth cornerstone mission in the ESA science programme. With a 3.5 m Cassegrain telescope it is the largest space telescope ever launched. It is performing photometry and spectroscopy in approximately the 55-671 µm range, bridging the gap between earlier infrared space missions and groundbased facilities.
European Space Agency, van der werf et al., 2012, 'Herschel spectra of low-z QSOs: measuring radiative feedback comma radiation pressure and star formation', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-jjqj71x
