J/MNRAS/341/1093 The Southern SHARC catalogue (Burke+, 2003) ================================================================================ The Southern SHARC Catalogue: a ROSAT survey for distant galaxy clusters Burke D.J., Collins C.A., Sharples R.M., Romer A.K., Nichol R.C. =2003MNRAS.341.1093B ================================================================================ ADC_Keywords: Clusters, galaxy ; Redshifts ; Positional data ; X-ray sources Keywords: catalogues ; surveys ; galaxies: clusters: general ; X-rays: galaxies: clusters Mission_Name: ROSAT Description: The Southern Serendipitous High-redshift Archival Cluster (SHARC) catalogue is a X-ray selected catalogue of galaxy clusters detected in deep ROSAT observations. The survey area is 17.7 deg^2 and is selected from long (greater than 10 ks) ROSAT exposures with a declination < +20 deg and excluding the Galactic plane (excluding galactic latitudes within the range [-20,20] deg). Optical follow-up was performed to confirm the presence of a galaxy cluster and measure its redshift. The final catalogue contains 32 galaxy clusters with redshifts between 0.05 and 0.70 and X-ray luminosities between 7x10^35 W and 4x10^37 W. Above a redshift of 0.3 - which forms the primary subsample of the survey - there are 16 clusters; the X-ray luminosities of these clusters are all greater than 2x10^36 W. All X-ray luminosities are quoted in the 0.5-2.0 keV band and were calculated using an Einstein-de Sitter cosmology with H_0 set to 50 km/s/Mpc. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file clusters.dat 173 32 The 32 clusters in the Southern SHARC sample selfn.dat 20 1092 Selection function for the Southern SHARC survey (as shown in Figure 7) fields.dat 98 66 ROSAT observations used in the Southern SHARC survey (Table A1) extsrcs.dat 112 96 All extended X-ray sources detected by the Southern SHARC survey (Table B1) numflux.dat 21 32 Number-flux points for Southern SHARC sample (Figure 14) -------------------------------------------------------------------------------- See also: J/ApJS/126/209 : The Bright SHARC Survey: The Cluster Catalog (Romer+, 2000) Byte-by-byte Description of file: clusters.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 15 A15 --- Name Southern SHARC catalogue name 17- 18 I2 h Rah Right Ascension 2000 (hours) 20- 21 I2 min Ram Right Ascension 2000 (minutes) 23- 26 F4.1 s Ras Right Ascension 2000 (seconds) 28 A1 - DE- Declination 2000 (sign) 30- 31 I2 deg DEd Declination 2000 (degrees) 33- 34 I2 arcmin DEm Declination 2000 (minutes) 36- 39 F4.1 arcsec DEs Declination 2000 (seconds) 41- 46 I6 --- ROR ROSAT observation request 48- 51 F4.1 arcmin Sep Angular distance: cluster to field center 53- 57 F5.3 --- Redshift Redshift of cluster 59 I1 --- nGal *Number of gals used to measure Redshift 61- 65 F5.2 arcmin r80 Aperture radius used to measure nSrc 67- 69 I3 % pArea *Percentage of aperture used 71- 75 F5.1 --- nSrc *Number of source counts in aperture 77- 82 F6.4 ct/s Ctot *Total cluster count rate 84- 87 F4.2 10+24/m2 nH *neutral Hydrogen column density 89- 94 F6.2 10-14mW/m2 f14 *Total cluster flux (0.5-2.0 keV) 96-100 F5.3 --- fracLerr *Fractional luminosity error 102-105 F4.2 10+37W Lrosat *Total cluster luminosity (0.5-2.0 keV) 107-110 F4.2 10+37W Lemss *Total cluster luminosity (0.3-3.5 keV) 112 I1 --- QF *[1-3] Quality flag of radial profile 114-173 A60 --- Matches Matches with other cluster catalogues -------------------------------------------------------------------------------- Note on nGal: The cluster redshift (the Redshift column) is calculated as the average of nGal galaxies. Note on pArea: Gives the area of the source aperture - as a percentage - left after masking out contaminating sources. Note on nSrc: The number of source counts is calculated from the source aperture after masking out contaminating sources. The estimated background signal in the aperture has been accounted for. Note on Ctot: The total cluster count rate is calculated by extrapolating the measured count rate to an infinite aperture. For clusters with pArea = 100, this amounts to multiplying the measured count rate by 1.25. If pArea is less than 100 then the conversion factor is larger to account for the signal excluded due to the presence of contaminating sources. Note on nH: Values taken from the compilation of 1984ApJ...287..633M (Marshall & Clark 1984). Note on f14: The total cluster flux was calculated from the Ctot value assuming a 6 keV thermal bremmstrahlung spectrum and accounting for Galactic absorption using the cross sections of Morrison & McCammon (1983). Note on fracLerr: The fractional luminosity error (delta L/L) is calculated from the Poisson error on the number of source counts (nSrc) added, in quadrature, to a 5 per cent error to account for uncertainties due to the use of a single temperature in the count rate to flux to luminosity conversion. Note on Lrosat: k-correction to convert observed 0.5-2.0 keV flux (f14) to 0.5-2.0 keV rest frame was calculated assuming a 6 keV thermal bremsstrahlung spectrum. Note on Lemss: k-correction to convert observed 0.5-2.0 keV flux (f14) to 0.3-3.5 keV rest frame was calculated assuming a 6 keV thermal bremsstrahlung spectrum. Note on QF: Indicates the quality flag of the radial profile of the cluster as discussed in section 3.2 of J/MNRAS/341/1093. -------------------------------------------------------------------------------- Byte-by-byte Description of file: selfn.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 7 F7.3 [mW/m2] lFlux *log10(Flux) 9- 13 F5.3 [arcsec] lTheta *log10(Core radius) 15- 19 F5.2 deg2 Area Survey Area -------------------------------------------------------------------------------- Note on lFlux: The flux used is the total cluster flux (so does not include any loses due to using a finite-sized aperture) and is given as log10(flux). The listed value gives the center of the bin and the bin width is 0.07 log10(mW/m2). Note on lTheta: Gives the core radius of the cluster in arcseconds, and is given as log10(core radius). The listed value gives the center of the bin and the bin width is 0.07 log10(arcsec). -------------------------------------------------------------------------------- Byte-by-byte Description of file: fields.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 16 A16 --- Name Field name 18- 23 I6 --- ROR ROSAT observation request 25- 27 A3 --- oSurveys Other surveys? 29- 33 I5 s Texp *Cleaned exposure time 35- 38 F4.2 10+24/m2 nH *neutral Hydrogen column density 40- 41 I2 h Rah Right Ascension 2000 (hours) 43- 44 I2 min Ram Right Ascension 2000 (minutes) 46- 49 F4.1 s Ras Right Ascension 2000 (seconds) 51 A1 - DE- Declination 2000 (sign) 53- 54 I2 deg DEd Declination 2000 (degrees) 56- 57 I2 arcmin DEm Declination 2000 (minutes) 59- 60 I2 arcsec DEs Declination 2000 (seconds) 62 I1 - nMask *Number of masked regions 64- 69 F6.2 arcmin X1 X position of masked region 1 71- 76 F6.2 arcmin Y1 Y position of masked region 1 78- 80 F3.1 arcmin R1 radius of masked region 1 82- 87 F6.2 arcmin X2 X position of masked region 2 89- 94 F6.2 arcmin Y2 Y position of masked region 2 96- 98 F3.1 arcmin R2 radius of masked region 2 -------------------------------------------------------------------------------- Note on Texp: Refers to the exposure time of the observation after cleaning for background flares and periods of bad aspect, as described in section 2.4.1 of J/MNRAS/341/1093. Note on nH: Values taken from the compilation of 1984ApJ...287..633M (Marshall & Clark 1984). Note on nMask: Number of regions masked from the observation. If equal to 1 then the X1, Y1, Y1 columns - and if equal to 2 the X2, Y2, R2 columns - list the location and radius of the circle excluded from the survey. The coordinate system has North and East the positive directions. Byte-by-byte Description of file: extsrcs.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 15 A15 --- Name Southern SHARC catalogue name 17- 22 I6 --- ROR ROSAT observation request 24- 25 I2 h Rah Right Ascension 2000 (hours) 27- 28 I2 min Ram Right Ascension 2000 (minutes) 30- 33 F4.1 s Ras Right Ascension 2000 (seconds) 35 A1 - DE- Declination 2000 (sign) 37- 38 I2 deg DEd Declination 2000 (degrees) 40- 41 I2 arcmin DEm Declination 2000 (minutes) 43- 46 F4.1 arcsec DEs Declination 2000 (seconds) 48- 51 A4 - ID *ID code 53- 60 A8 - z *Source redshift 62-112 A51 - Notes *Matches with other catalogues -------------------------------------------------------------------------------- Note on ID: Indicates the source identification. The first letter - if it is one of L, S, or I - refers to how the source was identified: L for from the literature (the NASA Extragalactic Database); a S indicates the source was spectroscopically identified; an I means that the identification was based on the R-band image taken at the ESO 3.6m telescope; otherwise the Digital Sky Survey image was used. The second letter lists which class of object the source belongs to: a C means a cluster; a G a galaxy; a Q for a QSO; an A for an AGN; and a S for a star. The letter P shows those sources for which an optical point source lies close to, or at, the centre of the X-ray emission; this source is taken to be the X-ray-emitting object. The letter M refers to those cases where the extended X-ray emission is actually from multiple point sources. A value of "-" means that the source remains un-identified, and brackets around the ID show that the source lies within 1 Mpc of the cluster identified in the Matches column. Note on z: The redshifts are obtained either from the literature or during the optical follow-up phase of the survey. For clusters with an ID of SC, the listed redshift is the average value of all the galaxies measured for that cluster, where the number in brackets gives the number of such galaxies. Note on Notes: Indicates other identifications for these sources (using a search radius of 1 arcmin): the main catalogues referred to are 2000ApJS..126..209R for BS and BSe (sources that are in Appendix~E only), 1998ApJ...502..558V for [VMF98], 2000MNRAS.311..456M for RIXOS, 2002ApJS..140..265P for WARP, 1994IAUC.6100....1W for 1WGA, and the Abell catalogue (1989ApJS...70....1A). -------------------------------------------------------------------------------- Byte-by-byte Description of file: numflux.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 2 I2 --- n Number of clusters 4- 11 E8.2 10-14mW/m2 flux Total cluster flux (0.5-2.0 keV) 13- 20 E8.2 /deg2 Nflux *N(>flux) for Southern SHARC sample -------------------------------------------------------------------------------- Note on Nflux: Calculated assuming an Einstein-de Sitter cosmology with H_0 set to 50 km/s/Mpc and that the cluster core radius is 250 kpc at all redshifts. -------------------------------------------------------------------------------- ================================================================================ (End) Douglas Burke [Harvard-Smithsonian Center for Astrophysics] 09-Jun-2003