Seminar by Dr. Marie Wingyee LAU (UC Riverside)

Understanding how quasars and their host galaxies co-evolve during the peak cosmic epoch is critical to studies of massive galaxy evolution. In this talk I will present three complementary data-driven collaborations in which I have played leading roles, that probe the circumgalactic medium, dust-reddened quasars, and associated line-of-sight absorbers. First, I study projected pairs of quasars in which the background quasar sightline passes close to the foreground quasar and probes its circumgalactic medium in absorption. High-resolution, high-S/N spectroscopy quantitatively measures the physical and kinematic properties of the cool gas. Second, I study a population of dust-reddened quasars called "extremely red quasars" that display markedly different properties from normal quasars. Adaptive-optics integral-field spectroscopy resolves their ionized gas outflows and interstellar medium, while wide-field integral-field spectroscopy reveals their extended gaseous halos. Third, I have initiated a study of gas inflows toward quasar-host galaxies. By measuring accurate systemic redshifts for the hosts, inflows can be detected via associated absorption lines along the line-of-sight at redshifted velocities. I will conclude with my outlook on observational astronomy and ways students can engage, from the perspective of a CUHK-educated researcher.