Matt Malkan

Title: New Observational Approaches to Galaxy Evolution Surveys

Abstract: Figuring out galaxy evolution--like much of astronomy--is distressingly 
dependent on which methods we use to find all the members of our sample.
What we want--an unbiased survey of galaxies over
a large cosmic volume, uniformly across a wide range of redshifts--
is a great observational challenge. 
I'll present two steps forward in meeting this goal.  The
first is Chun Ly's thesis investigation of galaxies in the Subaru Deep Field,
at the 'desert crossroads' of redshift z=1.5--2.5.  By combining all the leading
photometric methods for a very large sample, this work has given us a reasonably
complete view of galaxies across that crucial cosmic epoch.
A second, more radically different approach to the same problem is to obtain
infrared SPECTRA of all galaxies in a deep field without any photometric
pre-selection whatever.  We are now doing this with the WFC3 Infrared Spectroscopic
Parallels (WISP) survey.  By exploiting HST's unmatched capability for slitless
spectroscopy in the IR, WISP is surveying a large population of extreme line-emitting
galaxies.  They are too faint to be noticed by standard photometric searches, but
they account for a lot of the integrated cosmic star formation history.  The many thousands
of WISP galaxies include large numbers of extreme-starburst dwarfs, with low metallicity--
possible building blocks of modern galaxies