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CHANDFS7MS - Chandra Deep Field-South 7-Megasecond X-Ray Source Catalog

HEASARC
Archive

Overview

This table contains the X-ray source catalogs for the ~7 Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 square arcminutes. Utilizing WAVDETECT for initial source detection and ACIS Extract for photometric extraction and significance assessment, the authors have created a main source catalog (entries with source_sample = 'M' in this HEASARC table) containing 1,008 sources that are detected in up to three X-ray bands: 0.5-7.0 keV, 0.5-2.0 keV, and 2-7 keV. A supplementary source catalog entries with source_sample = 'S' in this HEASARC table) is also provided, including 47 lower-significance sources that have bright (Ks <~ 23m) near-infrared (NIR) counterparts. The authors have identified multiwavelength counterparts for 992 (98.4%) of the 1,008 main-catalog sources, and they have collected redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts.

Based on the X-ray and multiwavelength properties, the authors have identified 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous ~4 Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. The observations utilized in this survey have achieved unprecedented X-ray sensitivity with average flux limits over the central ~1 arcmin2 region of ~1.9 x 10-17, 6.4 x 10-18, and 2.7 x 10-17 erg cm-2 s-1 in the three X-ray bands, respectively. In the reference paper, the authors provide cumulative number-count measurements observing, for the first time, that normal galaxies start to dominate the X-ray source population at the faintest 0.5-2.0 keV flux levels. The highest X-ray source density reaches ~50,500 deg-2, and 47% +/- 4% of these sources are AGNs (~23,900 deg-2).

The authors adopted a binomial no-source probability value, PB < 0.007 as the criterion to prune their initial candidate source list and generate a main source catalog, which includes 1,008 sources with a ~97% multiwavelength-identification rate. This adopted PB threshold will have inevitably rejected real X-ray sources. To recover some of these real sources, the authors created a supplementary source catalog that contains lower-significance X-ray sources that have bright optical/NIR counterparts; the chance of a bright optical/NIR source being associated with a spurious X-ray detection is quite small. A total of 47 candidate CDF-S sources having 0.007 <= PB < 0.1 are associated with bright, Ks <= 23m, TENIS sources, where the false-match rate is only 1.7%, and these 47 sources constitute the supplementary catalog.

A Galactic column density of NH,Gal = 8.8 * 1019 cm-2 along the line of sight to the CDF-S is assumed in this study. All quoted magnitudes are in the AB system. A cosmology with H0 = 67.8 km s-1 Mpc-1, OmegaM = 0.308, and OmegaLambda = 0.692 (Planck Collaboration et al. 2016 values) is used to calculate luminosities.

This HEASARC table contains the 1,008 sources from the main Chandra source catalog (these entries are identified by the HEASARC-created source_sample parameter being set to 'M' in this table) and the 47 lower-significance sources from the supplementary NIR-bright Chandra source catalog (these entries are identified by the HEASARC-created source_sample parameter being set to 'S' in this table). This table thus has 1,055 entries.


Catalog Bibcode

2017ApJS..228....2L

References

The CHANDRA Deep Field-South Survey: 7 Ms Source Catalogs
    Luo B., Brandt W.N., Xue Y.Q., Lehmer B., Alexander D.M., Bauer F.E.,
    Vito F., Yang G., Basu-Zych A.R., Comastri A., Gilli R., Gu Q.-S.,
    Hornschemeier A.E., Koekemoer A., Liu T., Mainieri V., Paolillo M.,
    Ranalli P., Rosati P., Schneider D.P., Shemmer O., Smail I., Sun M.,
    Tozzi P.,  Vignali C., Wang J.-X.
   <Astrophys. J. Suppl. Ser., 228, 2-2 (2017)>
   =2017ApJS..228....2L    (SIMBAD/NED BibCode)

Provenance

This table was created by the HEASARC in March 2017 based upon electronic versions of Tables 4 and 5, the 'Main Chandra Source Catalog' and the 'Supplementary NIR-Bright Chandra Source Catalog', respectively, which were obtained from the ApJS website.

HEASARC Implementation

In this representation, the HEASARC has replaced values of -1.00 (which were used in the machine-readable version of table 4 and 5 obtained from the ApJS web site to indicate the absence of valid data values) for the following parameters by nulls: all magnitudes, positions and redshifts, the offset, the intrinsic absorption column density nH, the rest-frame X-ray luminosity (rf_lx), the absorption-corrected X-ray luminosity (abs_corr_lx), and the errors in the band counts (fb_counts_neg_err, fb_counts_pos_err, hb_counts_neg_err, hb_counts_pos_err, sb_counts_neg_err, sb_counts_pos_err), the band ratio (band_ratio_neg_err and band_ratio_pos_err) and the photon index (photon_index_neg_err and photon_index_pos_err).

Parameters

Source_Sample
This parameter is set to 'M' for the 1,008 sources from the main Chandra source catalog and is set to 'S' for the 47 lower-significance sources from the supplementary NIR-bright Chandra source catalog.

XID_Source_Number
A unique identification source number, i.e., the XID number, for sources listed in order of increasing J2000.0 Right Ascension within each sample (the main and supplementary NIR-bright sources). To uniquely identify an X-ray source in this HEASARC table which contains both samples, both the xid_source_number and the source_sample must be specified.

Name
The primary source designation in the style recommended by the Dictionary of Nomenclature of Celestial Objects, using the prefix 'CXOCDFS' for Chandra X-ray Observatory Chandra Deep Field South and the J2000.0 Right Ascension and Declination truncated to 0.1 seconds of time in RA and to 1 arcsecond in Declination.

Alt_Name
An alternative source designation in the style recommended by the Dictionary of Nomenclature of Celestial Objects, which was created by the HEASARC using the prefix '[LBX2017]' for Luo, Brandt, Xue (2017) and the XID source number for sources in the main sample, and the prefix '[LBX2017] S' and the XID source number for sources in the supplementary NIR-bright sample.

RA
The Right Ascension of the Chandra X-ray source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors determined the X-ray source positions following the procedure detailed in Section 3.2 of the reference paper.

Dec
The Declination of the Chandra X-ray source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors determined the X-ray source positions following the procedure detailed in Section 3.2 of the reference paper.

LII
The Galactic Longitude of the Chandra X-ray source.

BII
The Galactic Latitude of the Chandra X-ray source.

Log_Min_NS_Prob
The minimum value of log PB for the Chandra X-ray source, where PB is the AE-computed binomial no-source probability defined in Section 3.2 and Equation (1) of the reference paper, among the three standard bands (full-band from 0.5 to 7 keV, soft-band from 0.5 to 2 keV and hard-band from 2 to 7 keV), More negative values of log PB indicate a more significant source detection. The authors set log PB = -99.0 for sources with PB = 0. The threshold for being included in the main catalog is PB < 0.007. The threshold for being included in the supplemental catalog is 0.007 =< PB < 0.1, and the presence of a bright (Ks =< 23) TENIS counterpart. The distributions of PB for sources in the candidate-list catalog with different minimum WAVDETECT false-positive probability thresholds are displayed in Figure 5 of the reference paper. Most of the main-catalog sources, 922 out of the 1008 (91.5%), have PB < 0.001 and are highly reliable (a >98% identification rate).

Log_Min_FP_Prob
The logarithm of the minimum wavdetect false-positive probability detection threshold for the Chandra X-ray source. More negative values of this parameter indicate a more significant source detection. The relatively loose WAVDETECT source-detection threshold of 10-5 introduced a non-negligible number of spurious detections in the initial candidate source list. The authors also performed WAVDETECT source searching with the more stringent false-positive probability thresholds of 10-6, 10-7, and 10-8. They then assigned a minimum WAVDETECT false-positive probability to each of the candidate sources according to the minimum WAVDETECT threshold value at which the source was detected.

Error_Radius
The 1-sigma (~68% confidence level) positional uncertainty of the Chandra X-ray source, in arcseconds, computed using Equation (2) from the reference paper. This is dependent on both the off-axis angle and the aperture-corrected net source counts. The 90% and 95% confidence-level positional uncertainties are approximately 1.6 and 2.0 times the 1-sigma positional uncertainty. See Section 4.1 of the reference paper.

Off_Axis
The off-axis angle in units of arcminutes, which is the separation between the source position and the average aim point of the 7 Ms CDF-S (Section 2.1 of the reference paper).

FB_Counts
The aperture-corrected net source counts in the full (0.5-7 keV) band. For sources undetected in a given band, this parameter lists the 90% confidence-level upper limit on the source counts while the two associated uncertainty columns are set to null values. See Section 4.4. of the reference paper.

FB_Counts_Neg_Err
The 1-sigma lower uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band)c.

FB_Counts_Pos_Err
The 1-sigma upper uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band).

SB_Counts
The aperture-corrected net source counts in the soft (0.5-2 keV) band. For sources undetected in a given band, this parameter lists the 90% confidence-level upper limit on the source counts while the two associated uncertainty columns are set to null values. See Section 4.4. of the reference paper.

SB_Counts_Neg_Err
The 1-sigma lower uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band).

SB_Counts_Pos_Err
The 1-sigma upper uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band).

HB_Counts
The aperture-corrected net source counts in the hard (2-7 keV) band. For sources undetected in a given band, this parameter lists the 90% confidence-level upper limit on the source counts while the two associated uncertainty columns are set to null values. See Section 4.4. of the reference paper.

HB_Counts_Neg_Err
The 1-sigma lower uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band).

HB_Counts_Pos_Err
The 1-sigma upper uncertainty in the value of the counts in the corresponding band for the Chandra X-ray source (set to null if the source was not detected in this band).

Source_Flag
This parameter contains codes for photometric notes on individual sources. Sources covered by less than 20 of the 102 CDF-S observations are marked with 'E' and sources in crowded regions are marked with 'C' The other sources have this column set to blank values. See Section 4.4 of the reference paper.

Ctrpart_Catalog
The catalog from which the primary counterpart to the Chandra X-ray source was selected, being, in order of priority, one of the following six catalogs: CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS. There are 710, 26, 187, 49, 4, and 16 primary counterparts from these six catalogs, respectively. The references for these catalogs are as follows:

      CANDELS = CANDELS + 3D-HST HST WFC3 F125W+F140W+F160W combined catalog,
                Skelton et al. (2014, ApJS, 214, 24);
      GOODS-S = GOODS-S HST version r2.0z z-band catalog,
                Giavalisco et al. (2004, ApJ, 600, L93);
      GEMS    = Galaxy Evolution from Morphologies and SEDs (GEMS) HST z-band
                catalog, Caldwell et al. (2008, ApJS, 174, 136);
      TENIS   = TENIS Ks-band catalog,
                Hsieh et al. (2012, ApJS, 203, 23);
      WFI     = Wide Field Imager (WFI) R-band catalog,
                Giacconi et al. (2002, ApJS, 139, 369);
                Giavalisco et al. (2004, ApJ, 600, L93);
      SEDS    = Spitzer Extended Deep Survey (SEDS) Infrared Array Camera
                (IRAC) 3.6 um catalog,
                Ashby et al. (2013, ApJ, 769, 80).
  

Offset
The measured offset between the X-ray source and its multiwavelength counterpart, in arcseconds. Sources without multiwavelength identifications have this parameter's value set to null

Ctrpart_Note
Counterpart notes on individual sources, as follows:

  Manual      = sources with their counterparts selected manually;
  Pair        = sources matched to the same counterparts;
  Off-nuclear = sources that are candidates for being off-nuclear sources;
  Jet         = sources that are candidates for being extended jet/lobe emission.
  
There are six sources marked as 'Manual', three as 'Manual+Off-nuclear', one as 'Off-nuclear', one as 'Pair+Off-nuclear', two as 'Pair', one as 'Pair+Manual+Off- nuclear', one as 'Pair+Jet', and one as 'Pair+Off-nuclear/Jet'. The other sources have this parameter set to blank values. See Section 4.2 of the reference paper.

Wfi_RA
The Right Ascension of the WFI R-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Wfi_Dec
The Declination of the WFI R-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Wfi_Rmag
The R-band AB magnitude of the counterpart to the X-ray source in the WFI catalog. Sources without counterparts have their magnitudes set to nulls.

Goodss_RA
The Right Ascension of the GOODS-S HST r2.0z z-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Goodss_Dec
The Declination of the GOODS-S HST r2.0z z-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Goodss_Zmag
The GOODS-S HST version r2.0z z-band magnitude of the counterpart to the X-ray source. Sources without counterparts have their magnitudes set to nulls.

Gems_RA
The Right Ascension of the HST GEMS z-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Gems_Dec
The Declination of the HST GEMS z-band counterpart to the X-ray source, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Gems_Zmag
The GEMS HST z-band magnitude of the counterpart to the X-ray source. Sources without counterparts have their magnitudes set to nulls.

Candels_RA
The Right Ascension of the counterpart to the X-ray source in the CANDELS + 3D-HST HST WFC3 F125W+F140W +F160W combined catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Candels_Dec
The Declination of the counterpart to the X-ray source in the CANDELS + 3D-HST HST WFC3 F125W+F140W +F160W combined catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Candels_F125w_Mag
The HST F125W-band magnitude of the counterpart to the X-ray source in the CANDELS + 3D-HST HST WFC3 F125W+F140W +F160W combined catalog.

Tenis_RA
The Right Ascension of the counterpart to the X-ray source in the TENIS Ks-band catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Tenis_Dec
The Declination of the counterpart to the X-ray source in the TENIS Ks-band catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Tenis_Ks_Mag
The Ks-band magnitude of the counterpart to the X-ray source in the TENIS catalog.

Seds_RA
The Right Ascension of the counterpart to the X-ray source in the Spitzer Extended Deep Survey (SEDS) Infrared Array Camera (IRAC) 3.6-micron catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Seds_Dec
The Declination of the counterpart to the X-ray source in the Spitzer Extended Deep Survey (SEDS) Infrared Array Camera (IRAC) 3.6-micron catalog, in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI).See Section 4.2 of the reference paper for more details).

Seds_3p6_um_Mag
The Spitzer/IRAC 3.6-um magnitude of the counterpart to the X-ray source in the SEDS catalog.

VLA_RA
The Right Ascension of the counterpart to the X-ray source in the Very Large Array (VLA) 1.4-GHz catalog of Miller et al. (2013, ApJS, 205, 13), in the in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI). See Section 4.2 of the reference paper for more details.

VLA_Dec
The Declination of the counterpart to the X-ray source in the Very Large Array (VLA) 1.4-GHz catalog of Miller et al. (2013, ApJS, 205, 13), in the in the selected equinox: this was given in J2000.0 equatorial coordinates to a precision of 10-6 degrees in the original table. The authors cross-matched the positions of their primary multiwavelength counterparts with the positions of the Chandra X-ray sources using likelihood-ratio matching. Sources without counterparts have their corresponding Right Ascension and Declination values set to null values and their magnitudes also set to nulls. The authors identified primary counterparts for 982 (97.4%) of the 1,008 main-catalog sources, and 701, 26, 186, 49, 4, and 16 of them are from the CANDELS, GOODS-S, GEMS, TENIS, WFI, and SEDS catalogs, respectively. There were no primary counterparts selected from the VLA catalog. The false-match probabilities for the matches found in the seven catalogs range from 0.14% (VLA) to 4.0% (WFI). See Section 4.2 of the reference paper for more details.

VLA_20_cm_Mag
The AB magnitude m1.4GHz of the VLA 1.4-GHz counterpart to the X-ray source from the Miller et al. (2103) radio flux density catalog, calculated by m1.4GHz = -2.5*log fnu - 48.6, where fnu is the 1.4-GHz flux density in erg s-1 cm-2 Hz-1.

Spect_Redshift
The spectroscopic redshift of the source. The spectroscopic redshifts for stars were set to zero. Sources without spectroscopic redshifts have this parameter set to null. See Section 4.3 of the reference paper.

Spect_Redshift_Flag
A quality flag for the quoted spectroscopic redshift: 'Secure' or 'Insecure'.

Ref_Spect_Redshift
The reference code for the catalog from which the spectroscopic redshift was collected, coded as follows:

    null = No spectroscopic redshift;
       1 = Colless et al. (2003, astroph, 6581);
       2 = Szokoly et al. (2004, ApJS, 155, 271);
       3 = Zheng et al. (2004, ApJS, 155, 73);
       4 = Doherty et al. (2005, MNRAS.361, 525);
       5 = Mignoli et al. (2005, A&A, 437, 883);
       6 = Ravikumar et al. (2007, A&A, 465, 1099);
       7 = Kriek et al. (2008, ApJ, 677, 219);
       8 = Vanzella et al. (2008, A&A, 478, 83);
       9 = Treister et al. (2009, ApJ, 693, 1713);
      10 = Wuyts et al. (2009, ApJ, 706, 885);
      11 = Balestra et al. (2010, A&A, 512, A12);
      12 = Silverman et al. (2010,  ApJS, 191, 124);
      13 = Casey et al. (2011, MNRAS, 411, 2739);
      14 = Feruglio et al. (2011, ApJ, 729, L4);
      15 = Xia et al. (2011, AJ, 141, 64);
      16 = Cooper et al. (2012, MNRAS, 425, 2116);
      17 = Iwasawa et al. (2012, A&A, 546, A84);
      18 = Mao et al. (2012, MNRAS, 426, 3334);
      19 = Kurk et al. (2013, A&A, 549, A63);
      20 = LeFevre et al. (2013, A&A, 559, A14);
      21 = Rauch et al. (2013, MNRAS, 431, L68);
      22 = Del Moro et al. (2014, ApJ, 786, 16);
      23 = Hsu et al. (2014, ApJ, 796, 60);
      24 = Morris et al. (2015, AJ, 149, 178);
      25 = Santini et al. (2015, ApJ, 801, 97);
      26 = Tasca et al. (2016, arXiv160201842).
  

Phot_Redshift_L10
The photometric redshift of the source from Luo et al. (2010, ApJS, 187, 560). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Phot_Redshift_R11
The photometric redshift of the source from Rafferty et al. (2011, ApJ, 742, 3). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Phot_Redshift_H14
The photometric redshift of the source from Hsu et al. (2014, ApJ, 796, 60). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Phot_Redshift_S14
The photometric redshift of the source from Skelton et al. (2014, ApJS, 214, 24). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Phot_Redshift_S15
The photometric redshift of the source from Santini et al. (2015, ApJ, 801, 97). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Phot_Redshift_S16
The photometric redshift of the source from Straatman et al. (2016, ApJ, 830, 51). Sources without photometric redshifts from this reference have this parameter set to null. See Section 4.3 of the reference paper.

Redshift
The adopted redshift. Sources that lack redshifts have this parameter set to null values. See Section 4.3 of the reference paper for details of how the authors selected the preferred redshift.

Ref_Redshift
The reference code for the adopted redshift. Sources that lack redshifts have this parameter set to blank values. The meanings of the codes are as follows:

      H14   = Hsu et al. (2014, ApJ, 796, 60);
      L10   = Luo et al. (2010, ApJS, 187..560);
      R11   = Rafferty et al. (2011, ApJ, 742, 3);
      S14   = Skelton et al. (2014. ApJS, 214, 24);
      S16   = Straatman et al. (2016, ApJ, 830, 51);
      zSpec = spectroscopic redshift.
  

Redshift_Neg_Err
The 1-sigma lower uncertainty in the value of the redshift of the source if it is a photometric one. Sources that lack redshifts or have adopted spectroscopic redshifts have this parameter set to null values. See Section 4.3 of the reference paper.

Redshift_Pos_Err
The 1-sigma upper uncertainty in the value of the redshift of the source if it is a photometric one. Sources that lack redshifts or have adopted spectroscopic redshifts have this parameter set to null values. See Section 4.3 of the reference paper.

FB_Exposure
The effective exposure time, in seconds, derived from the exposure map in the full band. See Section 3.1 of the reference paper.

SB_Exposure
The effective exposure time, in seconds, derived from the exposure map in the soft band. See Section 3.1 of the reference paper.

HB_Exposure
The effective exposure time, in seconds, derived from the exposure map in the hard band. See Section 3.1 of the reference paper.

Band_Ratio
The X-ray band ratio, viz., the ratio between the hard-band and soft-band count rates, where the count rates were computed by dividing the aperture-corrected net counts by the effective exposure time. Band ratios for the 479 sources detected in either the soft band or the hard band, but not both, are the mode values from the Bayesian code, BEHR (Park et al. 2006, ApJ, 652, 610), i.e., they are not upper or lower limits, but are best-guess estimates) and the corresponding uncertainties were not calculated. For the 22 sources detected only in the full band, the band ratios cannot be constrained and no values are quoted for the band ratios or their errors for these sources.

Band_Ratio_Neg_Err
The 1-sigma lower uncertainty in the value of the band ratio of the source. For the 502 sources detected in both the soft and hard bands, the authors computed these uncertainties using the Bayesian code, BEHR.

Band_Ratio_Pos_Err
The 1-sigma upper uncertainty in the value of the band ratio of the source. For the 502 sources detected in both the soft and hard bands, the authors computed these uncertainties using the Bayesian code, BEHR.

Photon_Index
The effective power-law photon index Gammaeff of the X-ray source spectrum. The authors adopted a value of 1.4 for sources detected only in the full band, and the corresponding uncertainties are set to null values in such cases See Section 4.4 of the reference paper.

Photon_Index_Neg_Err
The 1-sigma lower uncertainty in the value of the effective power-law photon index of the source. Sources detected in either the soft band or the hard band, but not both, have their uncertainty columns set to null values as do sources detected only in the full band.

Photon_Index_Pos_Err
The 1-sigma upper uncertainty in the value of the effective power-law photon index of the source. Sources detected in either the soft band or the hard band, but not both, have their uncertainty columns set to null values as do sources detected only in the full band.

FB_Flux
The X-ray flux of the Chandra X-ray source in the full (0.5-7 keV) band, in erg s-1 cm-2. Negative values indicate 90% confidence-level upper limits on the fluxes that were derived from the upper limits on the source counts. Using XSPEC and the AE-generated merged spectral response files for each source, the authors converted the count rate or upper limit on the count rate to the corresponding flux or flux upper limit, assuming that the spectrum is a power law having an effective power-law photon index Gammaeff modified by Galactic absorption. See Section 4.4 of the reference paper.

SB_Flux
The X-ray flux of the Chandra X-ray source in the soft (0.5-2.0 keV) band, in erg s-1 cm-2. Negative values indicate 90% confidence-level upper limits on the fluxes that were derived from the upper limits on the source counts. Using XSPEC and the AE-generated merged spectral response files for each source, the authors converted the count rate or upper limit on the count rate to the corresponding flux or flux upper limit, assuming that the spectrum is a power law having an effective power-law photon index Gammaeff modified by Galactic absorption. See Section 4.4 of the reference paper.

HB_Flux
The X-ray flux of the Chandra X-ray source in the hard (2-7 keV) band, in erg s-1 cm-2. Negative values indicate 90% confidence-level upper limits on the fluxes that were derived from the upper limits on the source counts. Using XSPEC and the AE-generated merged spectral response files for each source, the authors converted the count rate or upper limit on the count rate to the corresponding flux or flux upper limit, assuming that the spectrum is a power law having an effective power-law photon index Gammaeff modified by Galactic absorption. See Section 4.4 of the reference paper.

Rf_Lx
The apparent rest-frame 0.5-7.0 keV luminosity (LX), in erg s-1, calculated from, in order of priority, the observed full-band, soft-band, or hard-band flux, applying the K correction assuming a power-law spectrum and also correcting for Galactic absorption. These X-ray luminosities have not been corrected for any intrinsic absorption and hence are referred to as 'apparent'. See Section 4.4 of the reference paper.

NH
The intrinsic absorption column density (NH,int), in H atoms cm-2, calculated using the Portable, Interactive, Multi- Mission Simulator (PIMMS) assuming that the intrinsic power-law spectrum has a fixed photon index of 1.8 and any effective photon index smaller than this value is caused by intrinsic absorption. For sources with effective photon indices greater than 1.8, the intrinsic absorption column densities were set to zero. See Section 4.4 of the reference paper.

Abs_Corr_Lx
The absorption-corrected intrinsic 0.5-7.0 keV luminosity (LX,int), in erg s-1, computed using the estimated intrinsic absorption column density (NH,int). See Section 4.4 of the reference paper.

Broad_Type
The X-Ray source type: AGN, star or galaxy. See Section 4.5 of the reference paper for the criteria that were adopted for this classification.

X11_Source_Number
The matched 4 Ms CDF-S source ID number (Xue et al. 2011, ApJS, 195, 10). A letter 'S' is added to the ID number if the matched source is from the supplementary catalog. Sources that lack 4 Ms CDF-S counterparts have this parameter left blank. See Section 4.6 of the reference paper.

X16_Source_Number
The matched 250 ks E-CDF-S source ID number (Xue et al. 2016, ApJS, 224, 15). A letter 'S' is added to the ID number if the matched source is from the supplementary catalog. Sources that lack 250 ks E-CDF-S counterparts have this parameter left blank. See Section 4.6 of the reference paper.

R13_Source_Number
The matched 3 Ms XMM-Newton CDF-S source ID number (Ranalli et al. 2013, A&A, 555, A42). Sources that lack 3 Ms XMM-Newton CDF-S counterparts have this parameter left blank. See Section 4.6 of the reference paper.

Class
The HEASARC Browse object classification based on the value of the broad_type parameter.


Contact Person

Questions regarding the CHANDFS7MS database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 16-Mar-2017