The interstellar medium is the fuel for star formation and AGN, and the sink for their feedback energy. It also records the history of star formation in its elemental abundances. The warm ionized gas is a major component of the ISM and is relatively easy to observe with optical spectroscopy. There are plenty of data, models, and analysis techniques. However, there are still a number of mysteries about the ionization mechanisms for such gas in quiescent galaxies and quiescent regions of galaxies. Even for star-forming regions which are most well studied, there are still a large number of discrepant results in the literature about their metallicity, their elemental abundance pattern, and ionization states. I would present our efforts in solving these mysteries and resolving those discrepancies, and describe a roadmap towards an era in which we can model the astrophysics of warm ionized gas with precision, in the same style as Precision Cosmology. I will also introduce the design of a cost-effective, high spectral resolution, integral field spectrograph. When paired with a small telescope like a telephoto lens, it could provide unprecedented data to help us better understand star-forming HII regions and the feedback of star formation.
BIO
Prof. Renbin Yan got his B.S. degree from Peking University in 2001 and his PhD from University of California at Berkeley in 2007 under the guidance of Marc Davis. He then moved to the University of Toronto and was an Ontario Postdoctoral Fellow. In 2010, he became an Assistant Research Scientist at New York University. He got a tenure-track faculty position at the University of Kentucky in 2012 and was promoted to a tenured associate professor in 2018. Dr. Yan's research interests cover the interstellar medium, stellar population, active galactic nuclei, and astronomical instrumentation. He is the Survey Scientist for the SDSS-IV MaNGA survey and the PI of the MaStar stellar library project.
Host: Zheng Cai
