ARCQUINCXO - Arches and Quintuplet Clusters Chandra X-Ray Point Source Catalog
The deep Chandra ACIS-I observation (Obs. ID: 4500) was carried out on 2004 June 9. The Arches cluster was placed about 1-arcmin away from the aim point to minimize the effect of the CCD gaps on mapping the extended X-ray emission around the cluster.
The interplay between star formation and the nuclear environment of our Galaxy: deep X-ray observations of the Galactic centre Arches and Quintuplet clusters. Wang Q.D., Dong H., Lang C. <Mon. Not. R. Astron. Soc., 371, 38-54 (2006)> =2006MNRAS.371...38W (SIMBAD/NED BibCode)
A running X-ray source number in order of increasing J2000.0 Right Ascension for the first 235 sources which have individual local false detection probablilities P <= 10^-7). Sources 236 to 244 are the 9 sources found in the vicinity (2 x 3 square arcminutes) of the Arches and Quintuplet clusters for which a looser significance (10^-7 < P <= 10^-5) of being false was adopted.
An alternative designation for the X-ray source using the '[WDL2006]' prefix (for Wang, Dong and Lang 2006) and the value of the source number parameter, as recommended by the CDS Dictionary of Nomenclature of Celestial Objects.
This parameter is set to 'L' to indicate those sources (numbers 236 through 244 inclusive) found in the vicinity (2 x 3 square arcminutes) of the Arches and Quintuplet clusters for which a looser significance (10^-7 < P <= 10^-5) of being false was adopted.
The preferred designation for the X-ray source using the 'CXOGCS' prefix (for Chandra X-Ray Observatory, Galactic Center Survey) and the J2000.0 coordinates (JHHMMSS.ss-DDMMSS.ss), as recommended by the CDS Dictionary of Nomenclature of Celestial Objects. Notice that in the reference paper, a slightly different (non-standard) prefix of 'CXGCS' was used.
The Right Ascension of the X-ray source in the selected equinox. This was given in J2000.0 coordinates to a precision of 0.01 seconds of time in the original table (implicitly in the name of the source).
The Declination of the X-ray source in the selected equinox. This was given in J2000.0 coordinates to a precision of 0.1 arcseconds in the original table (implicitly in the name of the source).
The Galactic Longitude of the X-ray source.
The Galactic Latitude of the X-ray source.
The positional uncertainty (1-sigma) of the X-ray source, in arcseconds, with the 1-sigma statistical error e calculated from the maximum-likelihood centroiding and an approximate off-axis angle-dependent systematic error E = 0.2" + 1.4"(r/8')^2, where r is the off-axis angle in arcminutes, added in quadrature (sqrt[e^2 + E^2]).
The on-axis X-ray source broad-band count rate B in counts per second, i.e., the sum of the exposure-corrected count rates in the four energy bands S1 (1 - 2.5 keV), S2 (2.5 - 4.0 keV), H1 (4 - 6 keV), and H2 (6 - 9 keV). In addition, S = S1 + S2, H = H1 + H2 and B = S + H.
The RMS uncertainty in the on-axis X-ray source broad-band count rate, in counts per second.
The hardness ratio, HR1, defined as HR1 = (H - S2)/(H + S2) where the band count rates are defined above. This is listed only for sources which have HR1 values with uncertainties less than 0.2.
The RMS uncertainty in HR1.
The hardness ratio, HR2, defined as HR2 = (H2 - H1)/(H) where the band count rates are defined above. This is listed only for sources which have HR2 values with uncertainties less than 0.2.
The RMS uncertainty in HR2.
This parameter flags the bands in which a source was detected (B, S, and/or H). The band which generated the most accurate X-ray centroid position is listed first.