Star Formation in Quasar Host Galaxies at Redshift 6: Millimeter Surveys   and New Insights from ALMA
  We have been carrying out a systematic survey of the star formation and ISM properties in the host galaxies of z~6 quasars. Our 250 GHz observations, together with available data from the literature, yield a sample of 14 z~6 quasars that are bright in millimeter dust continuum emission with estimated FIR luminosities of a few 10^12 to 10^13 Lsun. Most of these millimeter-detected z~6 quasars have also been detected in molecular CO line emission, indicating molecular gas masses on order of 10^10 Msun. We have searched for [C II] 158 micron fine structure line emission toward four of the millimeter bright z~6 quasars with ALMA and all of them have been detected. All these results suggest massive star formation at rates of about 600 to 2000 Msun/yr over the central few kpc region of these quasar host galaxies. 
Ran Wang, Jeff Wagg, Chris L. Carilli, Fabian Walter, Xiaohui Fan,   Frank Bertoldi, Dominik. A. Riechers, Alain Omont, Karl...
astro-ph.CO