WFC3IR Imaging of UV-Faint z6 Quasars: Star-Forming Host Galaxies of AGN in the Early Universe

Ever since their discovery in the 1960s, QSOs have been the best and most easily observed beacons to probe the distant universe. They are likely hosted by massive galaxies with a super-massive black hole (SMBH) as the central power-house. Building up the enormous supermassive black hole mass (> ~ 109 M) associated with SDSS quasars in cosmic epochs as early as z=6 represents a great theoretical challenge, for which direct images of their QSO hosts will provide vital information. HSTs superb resolution is essential to disentangle the QSO nucleus from the host galaxy. In this Cycle 20 HST project, we will image the host galaxies of five z=6 QSOs, and study surrounding objects at z=6 up to 4 Mpc from the QSOs. These observations give a unique opportunity to study the most massive galaxies at z6, probing the extremely luminous end of the luminosity function at these redshifts.