XBOOTES - XBOOTES: NDWFS Bootes Field X-Ray Point Source Catalog

Overview

The XBootes table contains the X-Ray point source catalog from a Chandra survey of the 9 square degrees Bootes field of the NOAO Deep Wide-Field Survey (NDWFS). This XBootes survey consists of 126 separate contiguous ACIS-I observations each of approximately 5000 s in duration. These unique Chandra observations allowed the authors to search for large-scale structure and to calculate X-ray source statistics over a wide, contiguous field of view with arcsecond angular resolution and uniform coverage. Optical spectroscopic follow-up observations and the rich NDWFS data set will allow the authors to identify and classify these X-ray-selected sources. Using wavelet decomposition, they have detected 4642 point sources with n >= 2 counts. In order to keep their detections ~ 99% reliable, they have limited their list to sources with n >= 4 counts. For a 5000 s observation and assuming a canonical unabsorbed active galactic nucleus (AGN) type X-ray spectrum, a 4 count on-axis source corresponds to a flux of 4.7 x 10^-15 ergs cm^-2 s^-1 in the soft (0.5-2 keV) band, 1.5 x 10^-14 ergs cm^-2 s^-1 in the hard (2-7 keV) band, and 7.8 x 10^-15 ergs cm^-2 s^-1 in the full (0.5-7 keV) band. The full 0.5-7 keV band n >= 4 count list contained in this HEASARC table has 3293 point sources. In addition to the point sources, 43 extended sources (not included in this HEASARC table) have been detected, consistent with the depth of these observations and the number counts of clusters. Presented here in the X-ray point source catalog for the XBootes survey are the source positions, X-ray fluxes, hardness ratios, and their uncertainties, for the 3293 sources with >= 4 counts in the full band.

Catalog Bibcode

2005ApJS..161....9K

References

Xbootes: An X-Ray Survey of the NDWFS Bootes Field. II. The X-ray Source Catalog
       Kenter A., Murray S.S., Forman W.R., Jones C., Green P., Kochanek C.S.,
       Vikhlinin A., Fabricant D., Fazio G., Brand K., Brown M.J.I., Dey A.,
       Jannuzi B.T., Najita J., McNamara B., Shields J., Rieke M.
      <Astrophys. J. Suppl. Ser. 161, 161, 9 (2005)>
      =2005ApJS..161....9K

Provenance

This table was created by the HEASARC in February 2006 based on the machine-readable version of Table 3 in the above paper which was obtained from the electronic ApJ website.

Parameters

Name
The IAU-registered name for the X-ray source, based on the J2000 equatorial coordinates and the 'CXOXB' prefix (for Chandra X-Ray Observatory XBootes survey).

RA
The Right Ascension of the X-ray source in the selected equinox. The RA was given in J2000 equatorial coordinates and to a precision of 0.01 seconds of time in the original source table.

Dec
The Declination of the X-ray source in the selected equinox. The Declination was given in J2000 equatorial coordinates and to a precision of 0.01 arcseconds in the original source table.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Error_Radius
The uncertainty in the source position, in arcseconds. This is estimated from the count rate and the 50% encircled energy radius at the source position relative to the pointing center.

FB_Counts
The full-band (0.5-7 keV) counts in the X-ray source.

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

HB_Counts
The hard-band (2-7 keV) counts in the X-ray source.

FB_Flux
The full-band (0.5-7 keV) flux of the X-ray source, in units of erg/s/cm². This has been calculated assuming Galactic absorption (column density NH = 1 x 10²⁰ cm^-3), an on-axis point source, a common X-ray AGN source power-law spectrum with a photon index Gamma = 1.7, and a common 5000 s equivalent exposure. This flux conversion has been done for the benefit of comparison with other surveys; the actual fluxes of the individual sources will of course depend on their specific spectra.

FB_Flux_Error
The uncertainty in the full-band (0.5-7 keV) flux, in units of erg/s/cm².

SB_Flux_Limit
This parameter is set to '<=' to indicate that the corresponding flux is an upper limit.

SB_Flux
The soft-band (0.5-2 keV) flux of the X-ray source, in units of erg/s/cm². This has been calculated assuming Galactic absorption (column density NH = 1 x 10²⁰ cm^-3), an on-axis point source, a common X-ray AGN source power-law spectrum with a photon index Gamma = 1.7, and a common 5000 s equivalent exposure. This flux conversion has been done for the benefit of comparison with other surveys; the actual fluxes of the individual sources will of course depend on their specific spectra.

SB_Flux_Error
The uncertainty in the soft-band (0.5-2 keV) flux, in units of erg/s/cm².

HB_Flux_Limit
This parameter is set to '<=' to indicate that the corresponding flux is an upper limit.

HB_Flux
The hard-band (2-7 keV) flux of the X-ray source, in units of erg/s/cm². This has been calculated assuming Galactic absorption (column density NH = 1 x 10²⁰ cm^-3), an on-axis point source, a common X-ray AGN source power-law spectrum with a photon index Gamma = 1.7, and a common 5000 s equivalent exposure. This flux conversion has been done for the benefit of comparison with other surveys; the actual fluxes of the individual sources will of course depend on their specific spectra.

HB_Flux_Error
The uncertainty in the hard-band (2-7 keV) flux, in units of erg/s/cm².

Exposure
The effective exposure time for the X-ray source, in seconds (s).

Eff_Area_Fraction
The effective area fraction for the X-ray source, being the effective area at the position of the X-ray source relative to the on-axis effective area.

Hardness_Ratio
The hardness ratio, HR, of the X-ray source, defined as HR = (h-s)/(h+s), where s is the number of counts detected in the 0.5-2 keV band and h is the number of counts detected in the 2-7 keV band. The hardness ratios have only been calculated for sources with >= 10 counts.

Hardness_Ratio_Pos_Err
The positive error in the hardness ratio corresponding to 90% confidence limits derived using the maximum likelihood method of Harris et al. (1993, The Einstein Observatory Catalog of IPC X-Ray Sources, Vol 1E, NASA TM-108401).

Hardness_Ratio_Neg_Err
The negative error in the hardness ratio corresponding to 90% confidence limits derived using the maximum likelihood method of Harris et al. (1993, The Einstein Observatory Catalog of IPC X-Ray Sources, Vol 1E, NASA TM-108401).

Contact Person

Questions regarding the XBOOTES database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:36:55 EDT