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First Insights into the SWIRE Galaxy Populations

Carol Lonsdale·Maria Polletta·Jason Surace·David Shupe·Fan Fang·C. Kevin Xu·Harding E. Smith·Brian Siana·Michael Rowan-Robinson·Tom Babbedge·Seb Oliver·Francesca Pozzi·Payam Davoodi·Frazer Owen·Deborah Padgett·Dave Frayer·Tom Jarrett·Frank Masci·JoAnne O'Linger·Tim Conrow·Duncan Farrah·Glenn Morrison·Nick Gautier·Alberto Franceschini·Stefano Berta·Ismael Perez-Fournon·Herve Dole·Gordon Stacey·Steve Sergeant·Marguerite Pierre·Matt Griffin·Rick Puetter
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Abstract

We characterize the SWIRE galaxy populations in the SWIRE validation field within the Lockman Hole, based on the 3.6-24$μ$ 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$μ$m and almost 350,000 at 24$μ$m; ~70,000 of these will be 5-band 3.6-24$μ$ 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]$μ$m color are found, as well as many objects very red in the 3.6-24$μ$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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Carol Lonsdale, Maria Polletta, Jason Surace, David Shupe, Fan Fang, C. Kevin Xu, Harding E. Smith, Brian Siana, Michael Rowan-Robinson, Tom Babbedge, Seb Oliver, Francesca Pozzi, Payam Davoodi, Frazer Owen, Deborah Padgett, Dave Frayer, Tom Jarrett, Frank Masci, JoAnne O'Linger, Tim Conrow, Duncan Farrah, Glenn Morrison, Nick Gautier, Alberto Franceschini, Stefano Berta, Ismael Perez-Fournon, Herve Dole, Gordon Stacey, Steve Sergeant, Marguerite Pierre, Matt Griffin, Rick Puetter. 2004-06-08. First Insights into the SWIRE Galaxy Populations. https://doi.org/10.1086/423206

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