Institute for Advanced Study Astrophysics Seminar
Cold Accretion, Hot Feedback, and the Bimodal Metallicity Distribution in the Circumgalactic Media of Galaxies at z < 1
ABSTRACT: Theoretical studies have raised a number of important questions about
the roles of gas inflows (accretion) and outflows (feedback) in galaxy
evolution. Unfortunately, galactic gas flows are likely to have low
densities and hence are difficult to observe with most techniques.
However, QSO absorption lines provide sensitive observational probes
of galactic flows, and the recent deployment of the Cosmic Origins
Spectrograph on HST has greatly expanded this capability by opening
access to QSO absorbers in the low-z Universe (where the
absorber-galaxy connections can really be studied in detail). This
talk will present results from several large HST+COS programs to study
galactic flows and missing baryons, including (1) statistical
comparisons of the gaseous halos of star-forming galaxies
vs. early-type (red and dead) galaxies (2) unambiguous evidence of
massive (and escaping) galactic winds from poststarburst galaxies, (3)
observations of cool and pristine (low-metallicity) gas in the halos
of high-metallicity star-forming galaxies, and (4) first results on
the physical conditions of circumgalactic gases.
Date & Time
March 12, 2013 | 11:00am – 12:00pm
Location
Bloomberg Hall Astrophysics LibrarySpeakers
Todd Tripp
Affiliation
University of Massachusetts