Session 9 - The Hubble Deep Field.
Display session, Monday, January 15
North Banquet Hall, Convention Center

[9.04] The Hubble Deep Field: Number Counts, Color-Magnitude and Color-Color Diagrams

The Hubble Deep Field (HDF) experiment is a unique project to explore at unprecedented depth and angular resolution the faintest and most distant galaxies. The project exploits the Hubble Space Telescope and the Wide Field Planetary Camera-2 to observe the same region of the sky for 150 continuous-viewing-zone orbits in 4 passbands, F300W, F450W, F606W and F814W, extending over a wavelength range that covers the whole optical window.

Thanks to the reduced sky background and the lack of the atmospheric blurring, the HDF images reach limiting AB magnitudes of 28.9, 29.5, 30.0 and 29.3, in each passband respectively, at the 3\, \sigma level. This allows study of broad-band spectral energy distribution, morphology and number count statistics for galaxies that span the largest, if not the whole, time interval of galaxy history. The vast majority of these galaxies are so faint that spectroscopic observations will not be possible for many years. Yet, the knowledge of their properties is essential to constraints the opoch(s) and physical processes of the galactogenesis, and the subsequent phases of the evolution. By providing accurate quantitative data, the HDF experiment will be a major and unique source of information of the properties of faint galaxies, which will significantly constrain the current theories of galaxy formation and evolution. Here we present preliminary number counts, color-magnitude and color-color diagrams for the 4 HDF frames. Copyright © 1997 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved.