S-COSMOS Overview
S-COSMOS is a deep infrared imaging survey carried out with the Spitzer Space Telescope. The survey covers the entire 2 square degrees of the Cosmic Evolution Survey (COSMOS) field. The S-COSMOS and COSMOS projects are closely coupled; therefore, their data are served as one large COSMOS Archive using IRSA's general search service, Atlas. S-COSMOS is part of the Spitzer Legacy Program. The data products released are part of the Spitzer General Observer Cycle 2 (GO2) program, including predominantly IRAC products (images and catalog). MIPS data include shallow images/catalogs covering the entire COSMOS field. There are also deep MIPS images covering only a test field of 0.16 sq. degrees for the upcoming GO3 program. The GO3 products will become public in September 2008.
S-COSMOS MIPS 70um and 160um Photometry Catalog (GO2 & GO3) Definitions
Gator serves the following MIPS 70um and 160um Photometry (GO2 & G03) Catalogs:
- (GO2) 70um Photometry Catalog, June 2007 (14 columns [9 delivered + 5 IRSA-created], 168 data rows).
- (GO3) 70um Photometry Catalog, Oct 2008 (12 columns [9 delivered + 5 IRSA-created], 168 data rows).
- (GO2) 160um Photometry Catalog, June 2007 (14 columns [9 delivered + 5 IRSA-created], 50 data rows).
- (GO3) 160um Photometry Catalog, Oct 2008 (12 columns [9 delivered + 5 IRSA-created], 50 data rows).
Please refer to the MIPS 70um/160um data delivery (GO2) README and (GO3) README files for general information on S-COSMOS catalogs and images.
The column descriptions can be found below.
Column Name | Data Type | Units | Description |
srcid | integer | n/a | Identification number of the source |
ra | float | degrees | Right Ascension (J2000) |
dec | float | degrees | Declination (J2000) |
xloc | float | pixels | X position in pixels on the mosaic image (Note, this column is not available for the GO3 catalogs) |
yloc | float | pixels | Y position in pixels on the mosaic image (Note, this column is not available for the GO3 catalogs) |
flux | float | uJy [micro-Jansky] | Flux density derived from point-source fitting using the APEX PRF (Point Response Function) method. [see note below] |
aperture5 | float | uJy [micro-Jansky] | Flux density measured for a large (radius=12) mosaic-pixel aperture, which may provide a good representation of the total flux for very bright and/or slightly resolved objects. |
snr | float | n/a | Signal-to-noise ratio of the PRF flux density (using 'flux' column above) |
chi2_dof | float | n/a | Chi-square fit parameter. Large values (>3) indicate that the source was not well-fitted by the input PRF and the source may be slightly resolved and/or very bright. Users may want to use the Aperture5 flux density and/or measure the source manually in these cases. |
(Note) APEX source extraction lists made based on "PRF" fluxes with S/N>7. The S/N>7 threshold has been shown previously to yield fairly reliable (non-spurious) source lists (e.g.Frayer et. al. 2006a). However, the photometric results have not been validated for these lists. In particular, careful background subtraction, deblending, and noise optimization has not yet been done. The main purpose of these lists is to identify the location of bright sources for future S-COSMOS 70um & 160um (aka Germanium (Ge)) processing. These are quick-look source lists; use at your own risk.