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J/A+A/462/449   Chandra point-source counts in galaxy cluster (Branchesi+, 2007)

Chandra point-source counts in distant galaxy clusters. Branchesi M., Gioia I.M., Fanti C., Fanti R., Cappelluti N. <Astron. Astrophys., 462, 449-458 (2007)> =2007A&A...462..449B
ADC_Keywords: Clusters, galaxy ; X-ray sources Keywords: galaxies: clusters: general - galaxies: active - X-rays: general - X-rays: galaxies: clusters - galaxies: nuclei Abstract: With the superb angular resolution of the Chandra Observatory, it is now possible to detect X-ray point sources, either embedded in galaxy clusters or along the cluster line of sight, which could not be resolved by previous instruments. This now allows studies of source counts in distant cluster fields. We want to analyze the inner region of clusters of galaxies to check for the presence of any over-density of X-ray point sources embedded in the gas diffuse emission. These point sources are possible AGN belonging to the clusters and could contaminate the cluster emission. We used a sample of 18 distant (0.25<z<1.01) galaxy clusters from the Chandra archive to construct the logN-logS, in both the soft and hard energy bands, for the X-ray point sources detected in the central cluster region to be compared with the counts of point sources detected in similarly deep fields without clusters. Description: The sample used in this study consists of 18 clusters of galaxies observed by the Chandra observatory with redshift in the range z=0.25-1.01. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 73 18 Cluster sample parameters and details of Chandra observations table2.dat 92 119 X-ray cluster region point sources
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 17 A17 --- Cluster Cluster name 19- 23 F5.3 --- z Spectroscopic redshift from literature 25- 26 I2 h RAh Right ascension (J2000) 28- 29 I2 min RAm Right ascension (J2000) 31- 32 I2 s RAs Right ascension (J2000) 34 A1 --- DE- Declination sign (J2000) 35- 36 I2 deg DEd Declination (J2000) 38- 39 I2 arcmin DEm Declination (J2000) 41- 42 I2 arcsec DEs Declination (J2000) 44- 47 I4 --- ObsID Identification number of the observation 49 A1 --- ACIS [IS] Detector where the aimpoint lies (I=ACIS-I or S=ACIS-S) 51- 52 A2 --- Mode [VF ] Observation mode (F=FAINT or VF=VFAINT) 54- 58 F5.1 ks ExpTime Exposure time corresponding to the nominal exposure filtered to exclude time periods of high background 60- 63 F4.2 10+20cm-2 NH Galactic hydrogen density column 65- 68 F4.2 10+35W Lsoft X-ray luminosity in (0.5-2.0keV) band 70- 73 F4.2 10+35W Lhard X-ray luminosity in (2.0-10.0keV) band
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 17 A17 --- Cluster Cluster name 19- 21 I3 arcsec Rext Search radius 23- 24 I2 --- Seq Source identification number, in the cluster (1) 26- 27 I2 h RAh Right ascension (J2000) 29- 30 I2 min RAm Right ascension (J2000) 32- 35 F4.1 s RAs Right ascension (J2000) 37 A1 --- DE- Declination sign (J2000) 38- 39 I2 deg DEd Declination (J2000) 41- 42 I2 arcmin DEm Declination (J2000) 44- 47 F4.1 arcsec DEs Declination (J2000) 49- 54 F6.2 ct Csoft ? Net counts in (0.5-2.0keV) energy band 55 A1 --- f_Csoft [*] Flag for non-used sources (2) 57- 62 F6.2 ct Chard ? Net counts in (2.0-7.0keV) energy band 63 A1 --- f_Chard [*] Flag for non-used sources (2) 65- 69 F5.2 aW/m2 Ssoft ? X-ray flux in (0.5-2.0keV) band (3) 71- 74 F4.2 aW/m2 e_Ssoft ? rms uncertainty on Ssoft 76- 80 F5.3 --- CNH Correction factor to be applied to the observed soft X-ray flux to obtain the Galactic absorption corrected X-ray flux 82- 86 F5.2 aW/m2 Shard ? X-ray flux in (2.0-10.0keV) band (3) 88- 92 F5.2 aW/m2 e_Shard ? rms uncertainty on S2.0-10.0keV
Note (1): Sources identified as [BGF2007] Cluster NN in Simbad. Note (2): source not used in Sect. 5 for the computation of the source counts since their flux is smaller than the flux corresponding to 20% of the sky coverage (see Appendix C). Note (3): The conversion factors allowed us to convert the 0.5-2.0keV band count rate to the observed X-ray fluxes in the same band and the 2.0-7.0keV band count rate to the observed X-ray flux in the 2.0-10.0keV band. Units are 10-15cgs (aW/m2)
History: * 11-Sep-2007: From electronic version of the journal * 24-Sep-2010: in table2, the "CNH" parameter was corrected from blank to the value of the first galaxy in the cluster (the correction is constant for the galaxies in a cluster)
(End) Patricia Vannier [CDS] 11-Sep-2007
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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