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We analyze the ROSAT Deep Cluster Survey (RDCS) to derive cosmological constraints from the evolution of the cluster X-ray luminosity distribution. The sample contains 103 galaxy clusters out to z=0.85 and flux-limit Flim=3 10^{-14} cgs (RDCS-3) in the [0.5-2.0] keV energy band, with a high-z extension containing four clusters at 0.901 10^{-14} cgs (RDCS-1). Model predictions for the cluster mass function are converted into the X-ray luminosity function in two steps. First we convert mass into intra-cluster gas temperature by assuming hydrostatic equilibrium. Then temperature is converted into X-ray luminosity by using the most recent data on the Lx-T relation for nearby and distant clusters. These include the Chandra data for seven distant clusters at 0.57, 10 pages, 4 figures, to appear in Astrophysical Journal

Starlight from distant galaxies ($z > 3$) is redshifted into the near infrared band with observed wavelengths from 2-8 $\mu$m. Most of the light is emitted by stars that have a peak emission at the 1.6 $\mu$m wavelength of the minimum of the H$^-$ opacity. We present simulated images of galaxy and star fields at 3, 4.7 and 8 $\mu$m, using the expected performance of the infrared camera on the Space InfraRed Telescope Facility (SIRTF). Standard astronomical image processing tools are used to locate sources, distinguish stars from galaxies, and create color-magnitude and color-color diagrams for the galaxies., Comment: poster paper presented at the June 1994 AAS meeting, 3 pages LaTex using aaspp.sty with appended color Postscript, GIF and JPEG figures, (330 kbytes) UCLA-ASTRO-ELW-94-03