ACDS V10.0 - Detailed Description of J/MNRAS/318/333

ACDS V10.0 - Sun Jan 19 06:22:37 CET 2025

| # Detailed Description of J/MNRAS/318/333 : Extended ROSAT Bright Cluster Sample (Ebeling+ 2000) |

Note : this is the description file of the original catalog. This HTML page corresponds well to the original description, but some minor changes in the format may have been introduced in the FITS output files in order to allow for arithmetic operations on quantities such as coordinates and times. h:m:s and d:m:s units are normally converted into degrees, and YYYY-MM-DD into julian days.
Similarly, some slight changes may have been introduced in the units; the value given in the HTML files supersedes the value indicated in the ReadMe file for this catalogue.

    J/MNRAS/318/333     Extended ROSAT Bright Cluster Sample    (Ebeling+ 2000)
    ================================================================================
    The ROSAT Brightest Cluster Sample - IV. The extended sample.
        Ebeling H., Edge A.C., Allen S.W., Crawford C.S., Fabian A.C., Huchra J.P.
       <Mon. Not. R. Astron. Soc. 318, 333 (2000)>
       =2000MNRAS.318..333E
    ================================================================================
    ADC_Keywords: Clusters, galaxy ; X-ray sources ; Redshifts

    Mission_Name: ROSAT

    Keywords: surveys - galaxies: clusters: general - X-rays: galaxies

    Abstract:
        We present a low-flux extension of the X-ray-selected ROSAT Brightest
        Cluster Sample (BCS) published in Paper I of this series. Like the
        original BCS and employing an identical selection procedure, the BCS
        extension is compiled from ROSAT All-Sky Survey (RASS) data in the
        northern hemisphere ({delta}>=0°) and at high Galactic latitudes
        (|b|>=20°). It comprises 99 X-ray-selected clusters of galaxies
        with measured redshifts z<=0.3 (as well as eight more at z>0.3) and
        total fluxes between 2.8x10-12 and 4.4x10-12erg/cm2/s in the
        0.1-2.4keV band (the latter value being the flux limit of the original
        BCS). The extension can be combined with the main sample published in
        1998 to form the homogeneously selected extended BCS (eBCS), the
        largest and statistically best understood cluster sample to emerge
        from the RASS to date. The nominal completeness of the combined sample
        (defined with respect to a power-law fit to the bright end of the BCS
        logN-logS distribution) is relatively low at 75per cent (compared with
        90per cent for the high-flux sample of Paper I). However, just as for
        the original BCS, this incompleteness can be accurately quantified,
        and thus statistically corrected for, as a function of X-ray
        luminosity and redshift. In addition to its importance for improved
        statistical studies of the properties of clusters in the local
        Universe, the low-flux extension of the BCS is also intended to serve
        as a finding list for X-ray-bright clusters in the northern hemisphere
        which we hope will prove useful in the preparation of cluster
        observations with the next generation of X-ray telescopes such as
        Chandra and XMM-Newton.

    File Summary:

           FileName      Lrecl  Records   Explanations

    ×                   80        .   This file
    × ReadMe            80        .   This file
    × table1.dat        92      107   The low-flux extension to the ROSAT
                                     Brightest Cluster Sample
    × refs.dat          83       29   References

    See also:
        IX/10 : ROSAT All-Sky Survey Bright Source Catalogue (Voges+ 1999)
        http://www.ifa.hawaii.edu/~ebeling/clusters/BCS.html :
                                                 The ROSAT Brightest Cluster Sample

    Byte-by-byte Description of file:  table1.dat

       Bytes Format Units   Label     Explanations

       1-  5  A5    ---     Notes     [VSc+* ] Notes (1)
       7- 20  A14   ---     Name      Name (2)
      22- 28  F7.3  deg     RAdeg     Right ascension (J2000)
      30- 36  F7.3  deg     DEdeg     Declination  (J2000)
      38- 41  F4.1 10+20cm-2 nH20     Column density of Galactic hydrogen from
                                       Stark et al. (1992, Cat. J/ApJS/79/77)
      43- 46  I4    s       Texp      Total RASS exposition time
      48- 51  F4.2  ct/s    CRVTP     Position Sensitive Proportional Counter (PSPC)
                                       count rate in Pulse Height Analyser (PHA)
                                       channels 11 to 235 originally detected by
                                       Voronoi Tesselation and Percolation (VTP,
                                       Ebeling & Wiedenmann, 1993, Phys. Rev. E,
                                       47, 704)
      53- 55  F3.1  arcmin  RadVTP    Equivalent radius sqrt(AVTP/{pi}) of the
                                       source detected by VTP
      57- 60  F4.2  ct/s    CR        Final PSPC count rate in PHA channels 11 to
                                       235 based on the original VTP count rate (3)
      62- 65  F4.2  ct/s    e_CR      rms uncertainty on CountRate
      67- 70  F4.1  keV     kT        Intra-cluster gas temperature used in the
                                       conversion from count rates to energy fluxes
      72- 77  F6.4  ---     z         Measured redshift
      79- 81  F3.1 10-15W/m2 FX       Unabsorbed X-ray energy flux in the
                                       0.1-2.4 keV band
      83- 87  F5.2  10+37W  LX        Intrinsic X-ray luminosity in the
                                       0.1-2.4 keV band (cluster rest frame)
      90- 91  I2    ---     r_z       Reference for redshift in refs.dat file

    Note (1): Flags:
          V = extended according to VTP
          S = extended according to SASS
          c = likely contamination from point sources
          + = serendipitous VTP detection
          * = redshift z>0.3
    Note (2): Where clusters appear to consist of two components, two entries
          (`a' and `b') are listed. We adopt cluster names in the following
          order of priority: Abell name, Zwicky name, other cluster name
          established in the literature, ROSAT RXJ name.
    Note (3): Statistical corrections for low surface brightness emission that has
          not been detected directly, and for contamination from point sources,
          have been applied.

    Byte-by-byte Description of file:  refs.dat

       Bytes Format Units   Label     Explanations

       1-  2  I2    ---     Refs      Reference number
       4- 22  A19   ---     BibCode   Bibcode
      24- 47  A24   ---     Aut       Author's name
      49- 83  A35   ---     Com       Comments

    History:
        Copied at http://www.ifa.hawaii.edu/~ebeling/clusters/BCS.html

    References:
      Allen et al., 1992MNRAS.259...67A
        Optical spectroscopy of the ROSAT X-ray brightest clusters
      Crawford et al., 1995MNRAS.274...75C
        Optical spectroscopy of the ROSAT X-ray brightest clusters - II
      Ebeling  et al., 1997ApJ...479L.101E
        The ROSAT Brightest Cluster Sample (BCS) - The cluster X-ray luminosity
        function within z=0.3
      Ebeling et al., 1998MNRAS.301..881E
        The ROSAT Brightest Cluster Sample (BCS) - I. The compilation of the
        sample and the cluster log N-log S distribution
      Crawford et al., 1999MNRAS.306..857C
        The ROSAT Brightest Cluster Sample (BCS) - III. Optical spectra of the
        central cluster galaxies
    ================================================================================
    (End)                                       Patricia Bauer  [CDS]    04-Dec-2000