(Proposal ID) S16B-071

(PI) Matsuoka, Yoshiki

(Proposal Title)
Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs)

(Abstract)
Quasars at high redshift (z > 6) are an important probe of the distant 
universe, for understanding the origin and progress of cosmic reionization, 
the early growth of supermassive black holes (SMBHs), and the evolution of 
host galaxies, among others. By exploiting the exquisite imaging data produced 
by the Hyper Suprime-Cam Strategic Program survey, we are carrying out a 
ground-breaking survey for high-z quasars. We have already achieved initial 
success in the past two semesters of observations, with 16 high-z quasars and 
14 high-z galaxies discovered. In order to advance this world-leading project 
further, here we propose a Subaru intensive program, involving 37 nights over 
6 semesters. We will explore quasar luminosities down to M_{1450} ~ -22 mag, 
i.e., ~2 mag deeper than any previous wide-field survey, and will discover 50 
and 20 new quasars at z~6 and z~7, respectively. Subaru/FOCAS (and possibly 
Gemini/GMOS) will be used for discovery observations, while we will also use 
Gemini/GNIRS to measure SMBH mass and metallicity for a subsample of the 
quasars we discover. By comparing the statistical properties such as the 
luminosity and SMBH mass functions with theoretical models, we aim to answer 
fundamental questions about the early history of the cosmos.