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First Insights into the SWIRE Galaxy Populations

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 نشر من قبل Harding E. Smith
 تاريخ النشر 2004
  مجال البحث فيزياء
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We characterize the SWIRE galaxy populations in the SWIRE validation field within the Lockman Hole, based on the 3.6-24$mu$ Spitzer data and deep U,g,r,r optical imaging within an area ~1/3 sq. deg for ~16,000 Spitzer-SWIRE sources. The entire SWIRE survey will discover over 2.3 million galaxies at 3.6$mu$m and almost 350,000 at 24$mu$m; ~70,000 of these will be 5-band 3.6-24$mu$ detections. The colors cover a broad range, generally well represented by redshifted spectral energy distributions of known galaxy populations, however significant samples of unusually blue objects in the [3.6-4.5]$mu$m color are found, as well as many objects very red in the 3.6-24$mu$m mid-IR. Nine of these are investigated and are interpreted as star-forming systems, starbursts and AGN from z=0.37 to 2.8, with luminosities from L$_{IR}$=10$^{10.3}$ to 10$^{13.7}$ L$_{odot}$

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