C-COSMOS Bright Source Catalog V2.1 Definitions
COSMOS Overview
The COSMOS Archive serves data taken for the Cosmic Evolution Survey (COSMOS) project. COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structural environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT, and others).
IRSA serves the COSMOS archive using the following search methods:
- Spatial search on all images and small catalogs, using Atlas
- Advanced search on only the larger catalogs, using Gator
C-COSMOS Bright Source Catalog V2.1
This is version 2.1 of the C-COSMOS Bright Source Catalog which consists of 1761 sources detected at uniform confidence in the 0.5 - 7 keV band of the Chandra-COSMOS survey. Details of the survey and initial results are found in the C-COSMOS catalog paper (Elvis et al. 2009, Paper I). The methods used to detect sources and generate the catalog are described in detail in Puccetti et al. 2009 (Paper II). Nearly 100%-complete multiwavelength source identification is discussed in Civano et al. 2009 (Paper III).
Notes/caveats
- 1749 sources have available aperture photometry. The other 12 had no available observations where the source extraction region did not dither off the chip edge and was not affected by a nearby source.
- Null values are represented by -99 or the floating point equivalent.
- For source bands with no detection the rate, flux, and snr columns are -99.0. The rate_err and flux_err are set to the corresponding upper limit.
- The hardness ratio was calculated starting with the EMLdetect rate values. Upper and lower limits were calculated using the Bayesian Estimation of Hardness Ratio code. Pseudo source and background count values were generated using the net count rate, background rate (per pixel), and a 3 arcsec source aperture and 5-20 arcsec background aperture.
C-COSMOS Bright Source Catalog V2.1 Column Definitions
Gator serves the C-COSMOS Bright Source Catalog v2.1 (40 columns [35 delivered + 5 IRSA-created], 1,761 data rows). The column descriptions can be found below.