Browse
this table...

CHAMPPSC - Chandra Multiwavelength Project (ChaMP) Point Source Catalog

HEASARC
Archive

Overview

This table represents the `Main Chandra Multiwavelength Project (ChaMP) X-Ray Point Source Catalog' and contains the basic parameters, photometry, and fluxes of 6512 ChaMP sources in 130 Chandra observations from Chandra Cycles 1 and 2. This table lists fluxes for 2 assumed spectral energy distributions with the photon indices of Gamma=1.4 and Gamma=1.7. This catalog was distributed by the ChaMP team based on the "Chandra Multiwavelength Project: X-ray Point Source Catalog (Kim et al., 2007, ApJS, 169, 401)", and was downloaded from http://hea-www.harvard.edu/CHAMP/. If you have any comments/questions on this catalog, please contact mkim @ cfa.harvard.edu or dkim @ cfa.harvard.edu.

The full Chandra Multiwavelength Project (ChaMP) X-ray point source catalog lists ~ 6800 X-ray sources detected in 149 Chandra observations covering ~ 10 square degrees. The full ChaMP catalog sample is 7 times larger than the initial published ChaMP catalog (Kim et al. 2004, ApJS, 150, 19). The exposure times of the fields in this sample range from 0.9 to 124 ks, corresponding to a deepest X-ray flux limit in the 0.5 - 8.0 keV band of 9 x 10^-16 ergs cm^-2 s^-1. The ChaMP X-ray data were uniformly reduced and analyzed with ChaMP-specific pipelines and then carefully validated by visual inspection. The ChaMP catalog includes X-ray photometric data in eight different energy bands as well as X-ray spectral hardness ratios and colors, source reliability, detection probability, and positional uncertainties. The false source detection rate is ~1% of all detected ChaMP sources, while the detection probability is better than ~ 95% for sources with counts >~ 30 and off-axis angle <5'. The typical positional offset between ChaMP X-ray source and their SDSS optical counterparts is 0.7" +/- 0.4", derived from ~ 900 matched sources.

This HEASARC table contains the main ChaMP catalog of 6512 X-ray point sources in 130 ChaMP fields observed once and in the overlapping fields which had the longest exposures. It does not contain the supplementary ChaMP catalog of 853 sources in 19 ChaMP overlapping fields with shorter exposure times.


Catalog Bibcode

2007ApJS..169..401K

References

  Chandra Multiwavelength Project: X-ray Point Source Catalog
      Kim M., Kim D., Wilkes B.J., Green P.J., Kim E., Anderson C.S.,
      Barkhouse W.A., Evans N.R., Ivezic Z., Karovska M., Kashyap V.L.,
      Lee M.G., Maksym P. Mossman A.E., Silverman J.D., Tananbaum H.D.
     <Astrophys. J. Suppl., 169, 401-429 (2007)>
     =2007ApJS..169..401K

Provenance

This table was created by the HEASARC in October 2006 based on the table http://hea-www.cfa.harvard.edu/CHAMP/IMAGES_DATA/champ_xpc.tab on the ChaMP website.

Parameters

Name
The recommended designation for ChaMP sources using the 'CXOMP' prefix for `Chandra X-Ray Observatory Multiwavelength Project' and the J2000 position for the X-ray source.

RA
The Right Ascension of the X-ray source in the selected equinox. This was given in J2000 decimal degrees to a precision of 10^-6 degrees in the original table.

Dec
The Declination of the X-ray source in the selected equinox. This was given in J2000 decimal degrees to a precision of 10^-6 degrees in the original table.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Off_Axis
The off-axis angle of the X-ray source from the aimed pointing of the X-ray observation, in arcminutes.

Error_Radius
The positional uncertainty of the X-ray source (95% confidence level), in arcseconds, using the empirical formula given in the paper (equation (12) in section 4.2 of KM06).

Extraction_Radius
The X-ray source extraction radius used (95% encircled energy radius at 1.5 keV), in arcseconds (see section 3.2 of KM06).

Exposure
The mean effective exposure time for the X-ray source after the vignetting correction has been applied, in seconds (see section 3.2.4 of KM06).

Counts
The net total counts for the X-ray source in the 0.5 - 8 keV energy band.

Counts_Error
The uncertainty in the net total counts in the 0.5-8 keV band.

SB_Counts
The net soft-band counts for the X-ray source (0.5 - 2 keV energy band).

SB_Counts_Error
The uncertainty in the net soft-band counts (0.5 - 2 keV).

HB_Counts
The net hard-band counts for the X-ray source (2 - 8 keV energy band).

HB_Counts_Error
The uncertainty in the net hard-band counts (2 - 8 keV).

Hardness_Ratio
The hardness ratio HR for the X-ray source defined as: HR=((Hc-Sc)/(Hc+Sc)), where Sc is the net counts in the 0.5-2 keV band and Hc is the net counts in the 2-8 keV band. When a source has no counts in the Sc or Hc band, the hardness ratio HR is 1 or -1, respectively, by definition.

Hardness_Ratio_Min
The 68% confidence lower limit value for the hardness ratio.

Hardness_Ratio_Max
The 68% confidence upper limit value for the hardness ratio.

C21_Color
The X-Ray color C21 for the X-ray source defined as C21=log(S1/S2), where S1 is the net counts in the 0.3 - 0.9 keV band, and S2 is the net counts in the 0.9 - 2.5 keV band

C21_Color_Min
The 68% confidence lower limit value for the X-ray color C21.

C21_Color_Max
The 68% confidence upper limit value for the X-ray color C21.

C32_Color
The X-Ray Color C32 for the X-ray source defined as C32=log(S2/H), where S2 is the net counts in the 0.9 - 2.5 keV band, and H is the net counts in the 2.5 - 8 keV band.

C32_Color_Min
The 68% confidence lower limit for the X-ray color C32.

C32_Color_Max
The 68% confidence upper limit for the X-ray color C32.

Flux
The total-band (0.5 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

Flux_Error
The uncertainty in the total-band (0.5 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

SB_Flux
The soft-band (0.5 - 2 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

SB_Flux_Error
The uncertainty in the soft-band flux (0.5 - 2 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

HB_Flux
The hard-band (2 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

HB_Flux_Error
The uncertainty in the hard-band flux (2 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.4.

Flux_1p7
The total-band (0.5 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

Flux_1p7_Error
The uncertainty in the total-band (0.5 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

SB_Flux_1p7
The soft-band (0.5 - 2 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

SB_Flux_1p7_Error
The uncertainty in the soft-band flux (0.5 - 2 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

HB_Flux_1p7
The hard-band (2 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

HB_Flux_1p7_Error
The uncertainty in the hard-band flux (2 - 8 keV) flux of the X-ray source, assuming an X-ray power-law spectrum with a photon index gamma = 1.7.

Source_Flag
This parameter contains flags which indicate notes concerning the source detection, as follows (see section 3.2.5 of KM06 for more details):

    Value:  Meaning

   31: Bad pixel/column exists within source extraction radius.
   37: Pile-up (see Chandra POG 2004).
   38: Uncertain source position due to the PSF effect
       (see section 3.1 of KM06).
   52: Same source candidate in multiple observations.
   53: Target of observation.
   55: Variable source (see section 3.3.2 of 2004, ApJS, 150, 19).
   61: Source region falls near the edge of the chip.
   62: Small portion of source region overlaps with nearby point sources.
   63: Large portion of source region overlaps with nearby point sources.
   64: Small portion of source region overlaps with nearby extended source.
   65: Large portion of source region overlaps with nearby extended source.
   66: Background region overlaps with a nearby point source.
   67: Background region overlaps with a nearby extended source.
   68: Source region falls inside the extended source.
  

Contact Person

Questions regarding the CHAMPPSC database table can be addressed to the HEASARC User Hotline.
Page Author: Browse Software Development Team
Last Modified: Tuesday, 10-Apr-2007 10:00:39 EDT