Mar 21

"Lyman Alpha Emitters and their Roles in Galaxy Formation"
Masami Ouchi, University of Tokyo, ICRR (Tinlsey Visiting Scholar)

I present observational results from recent Lya emitter (LAE) studies, and discuss a physical origin of LAEs and a connection with other high-z galaxies. I compare LAEs with other high-z populations in various observational properties such as stellar populations, clustering, metal abundance, and gas kinematics, and highlight how LAEs occupy an important place in galaxy formation. At the end of my talk, I introduce the forthcoming large LAE surveys, specifically our on-going program of Subaru/Hyper Suprime-Cam survey that increases sizes of LAE samples by a factor of 10-100 at z=2-7.

Apr 18

"Gas Around Galaxies - HVCs and the Lyalpha Forest"
Bart Wakker, University of Wisconsin, Madison

Recent progress in cosmological simulations has led to a more general dissemination of the idea that galaxies grow by both hot and cold-mode accretion. Directly observing these flows has remained difficult. but what happens in the final stages of the accretion processes may be observable through studies of the high-velocity clouds and gas in the Milky Way halo. I will present new results on the distances and metallicities and orbits of these objects and show how they provide evidence for the infall of low-metallicity gas onto the Milky Way. I will further discuss some data concerning the reservoir of gas that these clouds come from and what this tells us about galaxy halos and the Cosmic Web.