Herschel-ATLAS: Far-infrared properties of radio-loud and radio-quiet
  quasars
  We have constructed a sample of radio-loud and radio-quiet quasars from the
Faint Im- ages Radio Sky at Twenty-one centimetres (FIRST) and the Sloan
Digital Sky Survey Data Release 7 (SDSS DR7), over the H-ATLAS Phase 1 Area
(9h, 12h and 14.5h). Using a stacking analysis we find a significant
correlation between the far-infrared luminosity and 1.4-GHz luminosity for
radio-loud quasars. Partial correlation analysis confirms the intrinsic
correlation after removing the redshift contribution while for radio-quiet
quasars no partial correlation is found. Using a single-temperature grey-body
model we find a general trend of lower dust temperatures in the case of
radio-loud quasars comparing to radio-quiet quasars. Also, radio-loud quasars
are found to have almost constant mean values of dust mass along redshift and
optical luminosity bins. In addition, we find that radio-loud quasars at lower
optical luminosities tend to have on average higher FIR and 250-micron
luminosity with respect to radio-quiet quasars with the same optical
luminosites. Even if we use a two-temperature grey-body model to describe the
FIR data, the FIR luminosity excess remains at lower optical luminosities.
These results suggest that powerful radio jets are associated with star
formation especially at lower accretion rates.
