|Speaker||Talk Date||Talk Series|
|Evan Skillman, University of Minnesota||26 February 2009||Institute of Astronomy Colloquia|
Recent (< 0.5 Gyr) star formation histories have a large impact on the
observable properties of galaxies. The HST has allowed us to construct
spatially resolved star formation histories of nearby (D < 4 Mpc) galaxies
with a time resolution of roughly 30 Myr over the last 500 Myr.
These observations allow us to directly observe the strength and
spatial relationships of the recent star formation in these galaxies.
We can study the impact of recent star formation on the ISM.
In the case of the dwarf galaxy Holmberg II, it appears that most of
the holes in the ISM are caused by recent star formation, although not
all recent star formation results in the production of an HI hole.
We can also study the fraction of stars that are made in episodic
bursts and characterize the duration and spatial extents of these bursts.
>From a study of prototype dwarf starburst galaxies we find that the
durations of the starbursts are in excess of 100 Myr, and that the
star formation in the burst is distributed across the galaxies.
It is also interesting to compare the star formation histories as
embedded in the resolved stellar populations with the star formation
rate indicators available from H-alpha, UV, and IR observations.