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Legacy Program: GOODS |
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"GOODS: The Great Observatories Origins Deep Survey"
Principal Investigator: Mark Dickinson (National Optical Astronomy
Observatory)
Total Observatory Time: 647 hours
Co-Investigators include: Short AbstractThe Great Observatories Origins Deep Survey (GOODS) is a SIRTF Legacy Science project designed to study galaxy formation and evolution over a wide range of redshift and cosmic lookback time. We will trace the mass assembly history of galaxies, the evolution of their stellar populations, and the energetic output from star formation and active nuclei. GOODS builds on the deepest observations from NASA's other Great Observatories, Hubble and Chandra, and will be done in partnership with astronomers at Gemini and ESO, with a commitment of extensive ESO and NOAO observing time. By observing at wavelengths longer than 3 microns, SIRTF will measure the rest-frame near- and mid-infrared light from objects at 1 < z < 6, but very deep observations are needed to detect "ordinary" galaxies at these high redshifts.GOODS will utilize 647 hours of SIRTF observing time to survey approximately 300 square arcmin divided into two fields: the Hubble Deep Field North and the Chandra Deep Field South. These are among the most data-rich portions of the sky, and are the sites of the deepest observations from Hubble, Chandra, ESA's XMM-Newton, and from many ground-based facilities. Dividing our survey area provides insurance against cosmic variance due to galaxy clustering, and guarantees that astronomers in both hemispheres can carry out related observations. GOODS will image these fields at 3.6-8 microns with IRAC, with a mean exposure time per position of approximately 25 hours per band, reaching far deeper flux limits than observations planned for the Guaranteed Time Observer (GTO) programs. Ten-hour exposures with MIPS at 24 microns are also planned, pending on-orbit tests to establish that the data will achieve a significant gain in sensitivity relative to planned 20 minute GTO exposures. Finally, a pair of ultradeep IRAC fields are planned for the HDF-N, with total exposure times up to 100 hours, again pending on-orbit demonstration of instrument performance and source confusion. The GOODS IRAC observations are designed to detect rest-frame near-infrared light from the progenitors of galaxies like the Milky Way out to z=4, and will enable us to measure the stellar mass distribution of galaxies through most of cosmic history. The smaller, ultradeep IRAC field will probe the faintest sources and highest redshifts. The MIPS observations will offer the best opportunity to detect emission from dust-obscured star formation in ordinary galaxies out to z=2.5, and in concert with the Chandra data, will enable a census of supermassive central black holes in obscured and unobscured AGN. Overall, the data will provide the best lower limits to the extragalactic background light at 3.6-24 microns. By combining space- and ground-based observations, we will create a public data archive extending from X-ray through radio wavelengths, with a large sample of objects out to the highest known redshifts. This survey will give a uniquely comprehensive history of galaxies, from early epochs to the relatively recent past, and will serve as a bridge to future exploration in these wavelength and redshift regimes with the Next Generation Space Telescope.
The GOODS team has established a project Web site at http://www.stsci.edu/science/goods/ |
help@spitzer.caltech.edu http://ssc.spitzer.caltech.edu/legacy/abs/dickinson.html
