Seminario DAS: Observing the baryon cycle with ultra-strong Mg II absorbers

Speaker: Dr. Antonia Fernandez
Affiliation:  CASSACA- Universidad de Chile.

Abstract: The circumgalactic medium (CGM) is a giant reservoir of gas around galaxies. This component hosts a series of processes known as "the baryon cycle," in which intergalactic gas accretes onto galaxies, activates star formation, and in turn triggers powerful galactic-scale outflows. Historically, the cool component of the CGM has been studied via Mg II absorption lines in background quasars, given that these lines are easy to identify and reside in the optical window at z=0.1-2.5. In this talk, I will present my results on the most extreme subsample of these systems, known as ultra-strong Mg II absorbers. I will show how they can be used to trace galactic-scale outflows and accretion, providing new constraints on their properties and furthering our understanding of the baryon cycle.