Speaker: Yoshiki Matsuoka (Ehime U)

Time: 15:30-16:30 p.m., April 27, 2023, GM+8

Venue: Zoom Meeting ID: 890 8172 8606 Passcode: 000399

Abstract:

Quasars at high redshift (z > 6) are a unique probe of the distant Universe, for understanding the origin and progress of cosmic reionization, the early growth of supermassive black holes, and the evolution of quasar host galaxies and their dark matter halos, among other topics. This talk will start with a brief description of the motivation for and history of high-z quasar surveys, and then presents our SHELLQs project, which looks for high-z quasars based on the Subaru Hyper Suprime-Cam imaging data. The project has so far found ~200 low-luminosity quasars, which have played a vital role in establishing the quasar luminosity function at z = 6 and z = 7. We have also identified possible new classes of high-z quasars, namely, dust-reddened quasars, cousins of narrow-line Seyfert 1s, and candidate obscured quasars, among the low-luminosity population. The talk will be concluded with future prospects, highlighting our own JWST program and future facilities such as Rubin LSST, Euclid, and Roman.

Biography:

I received my Ph.D. in science in 2009 from the University Tokyo, and has developed academic career as a postdoc and a project assistant professor at Nagoya University, Princeton University, and National Astronomical Observatory of Japan. Then I moved to Ehime University as an associate professor, the present position, in 2017. My science interests include evolution of galaxies and supermassive black holes, quasar activity, and cosmic background radiation in the optical to infrared bands. I also serve as a member of the advisory boards for the two largest Japanese telescopes, i.e., Subaru 8.2m and Seimei 3.8m.

Source: School of Physics