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:

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

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.

Column Name Data Type Units Description
name string   Chandra-COSMOS source name
id int   Source ID
ra float deg RA
dec float deg Dec
pos_err float deg Position uncertainty
f_rate float cnt/s Rate (0.5 - 7 keV)
f_rate_err float cnt/s Rate error (0.5 - 7 keV)
f_flux float erg/cm2/s Flux (gamma=1.4) (0.5 - 10 keV)
f_flux_err float erg/cm2/s Flux error (0.5 - 10 keV)
f_snr float   Rate S/N ratio (0.5 - 7 keV)
f_exptime float ks Exposure time (0.5 - 7 keV)
f_cts_ap float cnt Source net counts (Aperture) (0.5 - 7 keV)
f_cts_ap_err float cnt Source net counts error (Aperture) (0.5 - 7 keV)
f_exptime_ap float ks Exposure time (Aperture) (0.5 - 7 keV)
s_rate float cnt/s Rate (0.5 - 2 keV)
s_rate_err float cnt/s Rate error (0.5 - 2 keV)
s_flux float erg/cm2/s Flux (gamma=1.4) (0.5 - 2 keV)
s_flux_err float erg/cm2/s Flux error (0.5 - 2 keV)
s_snr float   Rate S/N ratio (0.5 - 2 keV)
s_exptime float ks Exposure time (0.5 - 2 keV)
s_cts_ap float cnt Source net counts (Aperture) (0.5 - 2 keV)
s_cts_ap_err float cnt Source net counts error (Aperture) (0.5 - 2 keV)
s_exptime_ap float ks Exposure time (Aperture) (0.5 - 2 keV)
h_rate float cnt/s Rate (2 - 7 keV)
h_rate_err float cnt/s Rate error (2 - 7 keV)
h_flux float erg/cm2/s Flux (gamma=1.4) (2 - 10 keV)
h_flux_err float erg/cm2/s Flux error (2 - 10 keV)
h_snr float   Rate S/N ratio (2 - 7 keV)
h_exptime float ks Exposure time (2 - 7 keV)
h_cts_ap float cnt Source net counts (Aperture) (2 - 7 keV)
h_cts_ap_err float cnt Source net counts error (Aperture) (2 - 7 keV)
h_exptime_ap float ks Exposure time (Aperture) (2 - 7 keV)
hr float   Hardness ratio (H-S)/(H+S)
hr_lim_lo float   Hardness ratio 90% lower limit
hr_lim_hi float   Hardness ratio 90% upper limit