High-Redshift Quasars and Galaxies at the Epoch of Cosmic Reionization

In the last decade, we have witnessed great advances in detecting galaxiesand quasars at higher and higher redshifts, using both space andground-based telescopes. These distant objects provide a powerful tool toprobe the epoch of cosmic reionization, the last major phase transitions ofthe Universe. There are two parts in my talk, after a short introduction tocosmic reionization. The first part is about high-redshift (z>=6) galaxies.I will first present physical properties of the largest sample ofspectroscopically confirmed galaxies at z>=6. These objects have extremelydeep imaging data from the optical bands and HST near-IR bands, to theSpitzer mid-IR bands. The spectroscopic redshifts of the sample and thewealth of the multi-band data provide great advantages to measure variousphysical properties. Several interesting properties will be shown in thistalk. I will then present recent deep spectroscopy of z>7 galaxies, and showwhat the results tell us about cosmic reionization. In the second part ofthe talk I will talk about high-redshift (z>=6) quasars. I will mostlyreview our past and current searches of z>=6 quasars, their physicalproperties, and implications to reionization. Finally I will briefly mentionour future work on this topic.