BEGIN:VCALENDAR VERSION:2.0 CALSCALE:GREGORIAN PRODID:UW-Madison-Physics-Events BEGIN:VEVENT SEQUENCE:0 UID:UW-Physics-Event-3717 DTSTART:20150514T204500Z DTEND:20150514T220000Z DTSTAMP:20240329T072254Z LAST-MODIFIED:20150430T195518Z LOCATION:4421 Sterling Hall SUMMARY:A "New" Galaxy Formation Mechanism from Joint Galactic and Hig h Redshift Constraints\, Astronomy Colloquium\, Jonathan Bird\, Vander bilt University DESCRIPTION:
Very different data sets guide galaxy formation theory across cosmic history: from the global properties of >10^7 galaxies at high redshift (z>0.5) to the kinematics and chemistry of >10^6 stars here in the Milky Way. Traditional observational and computational lim itations have dictated independent study of these two regimes. I will discuss how this picture is changing rapidly and how viewing the MW as important boundary condition on galaxy evolution puts unprecedented d emands on galaxy formation theory. In particular\, I will discuss a no vel disk formation mechanism and its signature in current observations of the Milky Way and the resolved kinematics of high redshift galaxie s.
\nModern\, high-resolution\, cosmological galaxy formation s imulations reveal that disks can grow ‘upside-down’ in the sense t hat progressively younger stellar populations are born with increasing ly smaller vertical velocity dispersion\, tracing the kinematics of th e collapsing gas disk from which they form. We find that the upside-do wn model matches the most stringent observational constraints here in the MW\, including the steep stellar age-velocity relationship measure d in the solar neighborhood. I will argue that traditional interpretat ions of disk evolution from MW data contradict evidence from Integral Field Unit observations of high-redshift disk galaxies and must be rev ised. Our findings suggest that the ‘upside-down’ model is current ly the only self-consistent formation mechanism able to match kinemati c constraints from z~2 to z~0. I will conclude with preliminary\, yet tantalizing\, evidence connecting the star formation history of simula ted galaxies with their detailed morphology.
URL:https://www.physics.wisc.edu/events/?id=3717 END:VEVENT END:VCALENDAR