Galaxy Evolution and Globular Clusters

Scott C. Trager, UCO/Lick Observatory, University of California, Santa Cruz

I'm a fifth year graduate student at Lick Observatory, attempting to understand the evolution of galaxies throughout the history of the Universe. Other projects include the largest catalog of Galactic globular-cluster surface-brightness profiles to date.

I'm now in the ultra-competitive postdoctoral researcher job market. Here's my curriculum vitae in HTML or in PostScript.

Projects and preprints

Click on any of the highlighted titles to see cool pictures from that work.

Ages and metallicities of elliptical galaxies

In collaboration with S. M. Faber, G. Worthey, J. J. Gonzalez, and D. Burstein, I am comparing sophisticated models of galaxy evolution to low-resolution spectroscopy of nearby elliptical galaxies. These models allow us to derive accurate ages and metallicities of this important class of galaxies. In fact, we find that elliptical galaxies may span a much greater range of ages than previously thought---they may be as young as only a few billion years, or almost as old as the Universe itself. A preprint is forthcoming, and will appear here soon.

Studies of distant cluster galaxies

In collaboration with S. M. Faber, A. Dressler, and the WF/PC 1 IDT, I am studying the population of galaxies in distant clusters of galaxies. These galaxies existed when the Universe was only half or a third of its current age. We are training both the Hubble Space Telescope and the Keck Telescope on these clusters to get both ultra-deep, ultra-high-resolution imaging and spectroscopy in our effort to understand the evolution of galaxies throughout the history of the Universe.

All of the pictures on this page are images from the Hubble Space Telescope. They are galaxies in a cluster seen at a time halfway back to the Big Bang. Each box is about 175 thousand light-years across (if you were standing on a galaxy in the cluster), which is about 1 trillion trillion miles (yes, that's trillion twice), if you think in those sorts of units. Galaxies are big. But because they're so far away, they look really small---that's why we need the Space Telescope. Details like spiral arms, bars, and ring shapes have never been seen before at such huge distances.

A poster was presented on morphological aspects of this work at the January 1995 poster.

Surface-brightness profiles of Galactic globular-clusters

I. R. King, S. Djorgovski, and I have assembled the largest catalog of surface-brightness profiles of Galactic globular clusters to date. The profiles rest heavily on the Berkeley Globular Cluster Survey of King and Djorgovski. A paper, "A Catalog of Galactic Globular-Cluster Surface-Brightness Profiles", by S. C. Trager, Ivan R. King, and S. Djorgovski, is in the January 1995 issue of The Astronomical Journal. You can get PostScript versions of the text, the published version of Table 1, Table 2, and Figures 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j, 2k, 2l, 2m, 2n, 2o, and 2p. You can also get a poorly-scanned version of Figure 1. The rest of Table 1 is available here in ASCII form, and will also be available on the ApJ/AJ CD-ROM series.

Oh, and by the way---I use LINUX, too.

Scott C. Trager
UCO/Lick Observatory
University of California
Santa Cruz, CA 95064 or