| Description |
Understanding the formation and evolution of the first quasars, their supermassive black holes and host galaxies is one of the most important goals of both observational and theoretical astrophysics. In the last decade there has been immense progress in the discovery and study of z>6 quasars but since the discovery of SDSS J1148+5251 with z=6.42 by Fan et al(2003) almost a decade ago no quasar has been discovered with z>6.5. Recently, using data from the UKIDSS survey we have discovered a bright (K[Vega]=17.7) quasar ULAS J1120+0641 (Mortlock et al, 2011) which is the most distant quasar currently known at z=7.085, smashing the previous record of z=6.44 by a large margin. Furthermore, in the last few months, using data from the ESO VISTA public surveys, we have discovered three more quasars at z>6.5, with similar rest frame UV luminosity as ULAS J1120+0641 and redshifts of z=6.6, 6.8 and 6.9 respectively. Observations with the Plateu de Bure Interferometer of the z=7.085 quasar ULAS J1120+0641 have already revealed a significant detection of the [CII] 158micron cooling line which is the dominant interstellar medium (ISM) gas cooling line in star-forming galaxies confirming the presence of an ultraluminous star-forming galaxy associated with this quasar. In this proposal we shall carry out PACS and SPIRE photometry in the wavelength range 100-500microns corresponding to 12-60microns in the rest frame in this sample of four z>6.5 quasars with the goal of measuring the shape and luminosity of the FIR continuum in these primeval objects. These measurements will provide unique constaints on the star-formation rate, dust mass and dust temperature of the earliest massive star-forming galaxies. |
