|Time:||星期四, 12月 19, 2019, 02:00pm|
|Title:||The Hidden Baryons of the Milky Way|
|Speaker:||Dr. Yong Zheng (UC Berkeley)|
Galaxies are not lonely islands floating in the Universe. They host large gaseous envelopes of baryons, a.k.a., the circum-galactic medium (CGM), that exist far beyond a galaxy’s visible extent. Baryonic inflows from CGM replenish star-forming fuel in galaxies, whereas outflows from galaxies enrich the CGM. In this talk, I will describe the theoretical and observed distribution and flows of baryons in the CGM of our own Milky Way (MW), including how the MW’s disk hides up to half of its CGM from direct observation. I will then describe new techniques to generate synthetic observations of the CGM using the Enzo & FOGGIE cosmological simulations, and show how these can be used to reveal the hidden baryons in the MW’s CGM. Finally, I will briefly highlight the connections between low- and high-redshift CGM studies, including new applications that rely on fast radio bursts (FRBs).
I grew up in a beautiful village called Liaoyan (蓼沿) in southern China. I completed my bachelor’s degree in Astronomy in 2012 in Peking University, supervised by Prof. Richard de Grijs and Prof. Xiao-Wei Liu. From 2012 to 2018, I was advised by Prof. Mary Putman and Dr. Joshua Peek to pursue my Ph.D. degree at Columbia University in New York. I recently moved to Berkeley in Fall 2018 and continues my CGM research as a Miller Fellow hosted by Prof. Daniel Weisz. When not stargazing, activities such as climbing, running, yoga, and reading delightfully fill my spare time.
Host: Prof. Zheng Cai