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 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 (δ≥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:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 107 The low-flux extension to the ROSAT
Brightest Cluster Sample
refs.dat 81 29 References
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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
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Bytes Format Units Label Explanations
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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/π) 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
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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.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Refs Reference number
4- 22 A19 --- BibCode Bibcode
24- 47 A24 --- Aut Author's name
49- 83 A35 --- Com Comments
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History:
Copied at http://www.ifa.hawaii.edu/~ebeling/clusters/BCS.html
References:
Allen et al., 1992MNRAS.259...67A 1992MNRAS.259...67A
Optical spectroscopy of the ROSAT X-ray brightest clusters
Crawford et al., 1995MNRAS.274...75C 1995MNRAS.274...75C
Optical spectroscopy of the ROSAT X-ray brightest clusters - II
Ebeling et al., 1997ApJ...479L.101E 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 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 1999MNRAS.306..857C
The ROSAT Brightest Cluster Sample (BCS) - III. Optical spectra of the
central cluster galaxies
(End) Patricia Bauer [CDS] 04-Dec-2000