摘要：Being observed only one billion years after the Big Bang,z∼ 7 quasars are a unique opportunity for exploring the early Universe. However, only twoz∼ 7 quasars have been discovered in near-infrared surveys: the quasars ULAS J1120+0641 and ULAS J1342+0928 atz= 7.09 andz= 7.54, respectively. The rarity of these distant objects, combined with the difficulty of distinguishing them from the much more numerous population of Galactic low-mass stars, requires using efficient selection procedures. The Canada-France High-zQuasar Survey in the Near Infrared (CFHQSIR) has been carried out to search forz∼ 7 quasars using near-infrared and optical imaging from the Canada-France Hawaii Telescope (CFHT). Our data consist of ∼130 deg2of Wide-field Infrared Camera (WIRCam)Y-band images up to a 5σlimit ofYAB∼ 22.4 distributed over the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) Wide fields. After follow-up observations inJband, a first photometric selection based on simple colour criteria led us to identify 36 sources with measured high-redshift quasar colours. However, we expect to detect only ∼2 quasars in the redshift range 6.8
