|Herschel photometry of the nearest radio-quiet quasar
|PDS456 is a southern ultraluminous IRAS galaxy at redshift z=0.18. It hosts one of the nearest powerful optically-visible AGN, and is one of the most extreme known QSOs. It is hidden behind a significant amount of optical extinction, and so its host galaxy is relatively difficult to investigate. It is know to have a very luminous, hot dust SED, and yet is not detected at submm wavelengths. We propose a Herschel PACS and SPIRE photometry observation to determine exactly the broad-band shape of its spectral energy distribution (SED), and to provide a precise determination of its bolometric luminosity. The shape of the SED will provide help in interpreting the role of the AGN and possible star-formation activity in powering this object. Without Herschel, the peak of the SED of this unique source will not be known accurately, even as an excellent understanding of its morphology, gas dynamics and astrophysical processes is built up using ground-based adaptive optics imaging, ALMA and JWST.
|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.
|Publisher And Registrant
|European Space Agency
|European Space Agency, 2013, OT2_ablain_1, SPG v14.2.0. https://doi.org/10.5270/esa-kni1up5