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Title: (HerschelHerschel) observed Stripe 82 quasars and their host galaxies: connections between AGN activity and host galaxy star formation

Journal Article · · Astrophysical Journal
;  [1]
  1. Department of Astronomy, School of Physics, Peking University, Beijing, 100871 (China)

In this work, we present a study of 207 quasars selected from the Sloan Digital Sky Survey quasar catalogs and the Herschel Stripe 82 survey. Quasars within this sample are high-luminosity quasars with a mean bolometric luminosity of 10{sup 46.4} erg s{sup −1}. The redshift range of this sample is within z < 4, with a mean value of 1.5 ± 0.78. Because we only selected quasars that have been detected in all three Herschel-SPIRE bands, the quasar sample is complete yet highly biased. Based on the multi-wavelength photometric observation data, we conducted a spectral energy distribution (SED) fitting through UV to FIR. Parameters such as active galactic nucleus (AGN) luminosity, far-IR (FIR) luminosity, stellar mass, as well as many other AGN and galaxy properties are deduced from the SED fitting results. The mean star formation rate (SFR) of the sample is 419 M {sub ⊙} yr{sup −1} and the mean gas mass is ∼10{sup 11.3} M {sub ⊙}. All of these results point to an IR luminous quasar system. Compared with star formation main sequence (MS) galaxies, at least 80 out of 207 quasars are hosted by starburst galaxies. This supports the statement that luminous AGNs are more likely to be associated with major mergers. The SFR increases with the redshift up to z = 2. It is correlated with the AGN bolometric luminosity, where L{sub FIR}∝L{sub Bol}{sup 0.46±0.03}. The AGN bolometric luminosity is also correlated with the host galaxy mass and gas mass. Yet the correlation between L {sub FIR} and L {sub Bol} has higher significant level, implies that the link between AGN accretion and the SFR is more primal. The M {sub BH}/M {sub *} ratio of our sample is 0.02, higher than the value 0.005 in the local universe. It might indicate an evolutionary trend of the M {sub BH}–M {sub *} scaling relation.

OSTI ID:
22868991
Journal Information:
Astrophysical Journal, Vol. 824, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English