The Halos of Satellite Galaxies: Where Do Their Gas and Metals Go?

The Halos of Satellite Galaxies: Where Do Their Gas and Metals Go?

Satellite galaxies play a key role in the chemical evolution of the universe by redistributing gas and metals across halo environments. Their interactions with massive hosts through tidal and ram-pressure stripping regulate both their star-formation histories and the metal budget of their circumgalactic media (CGM). Yet, the diffuse CGM of satellite galaxies remains largely unexplored observationally. The Large Magellanic Cloud (LMC) provides the only well-characterized case to date. Our recent UV absorption-line studies with Hubble Space Telescope (HST) toward 28 background quasars reveal that the LMC’s metal-enriched CGM is truncated to one-tenth of its virial radius, consistent with ram-pressure stripping by the Milky Way’s hot corona. This provides a rare, direct view of how environmental forces remove or redistribute metals in low-mass galaxies. However future UV observations are needed to explore how typical the MW-LMC interaction is, and how satellites retain their gas and metals? This presentation will highlight how HST will uniquely trace metals in other satellite CGMs across the Local Group and beyond.

Sebastián López
Colloquium  Coordinator
DAS/UChile  – slopez@das.uchile.cl