X-ray Probes of Star Formation Outside the Local Universe

Ann Hornschemeier

X-rays provide a unique window into star formation processes, providing important information on the evolution of stellar endpoints and hot gas that cannot be obtained at other wavelengths. With Chandra we may study this X-ray emission at cosmologically interesting distances (0.1 < z < 2.0), placing constraints on X-ray emission over substantial evolutionary timescales (> 1 Gigayear). I will report on results from the two Chandra Deep Fields, which have recently been surveyed using the HST Advanced Camera for Surveys through the GOODS program. This includes physical constraints on the ULX population at appreciable look-back times, allowing us to make a strong link between star formation and ULX sources. I will discuss current efforts to better characterize the broad X-ray spectral properties of star-forming galaxies in the relatively nearby (z<0.1) Universe in a two-fold approach: (1) through a cross-correlation of the Chandra archive and the Sloan Digital Sky survey and (2) through upcoming Chandra observations of galaxies in the Coma cluster. This combined approach assembles a complete picture of the X-ray properties of star-forming galaxies.