J/MNRAS/301/881 The ROSAT brightest cluster sample - I. (Ebeling+, 1998)
The ROSAT brightest cluster sample - I.
The compilation of the sample and the cluster log N-log S distribution.
Ebeling H., Edge A.C., Boehringer H., Allen S.W., Crawford C.S.,
Fabian A.C., Voges W., Huchra J.P.
<Mon. Not. R. Astron. Soc. 301, 881 (1998)>
=1998MNRAS.301..881E 1998MNRAS.301..881E
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Surveys
Mission_Name: ROSAT
Keywords: catalogues - surveys - galaxies: clusters: general -
cosmology: observations - large-scale structure of Universe -
X-rays: galaxies
Abstract:
We present a 90 per cent flux-complete sample of the 201
X-ray-brightest clusters of galaxies in the northern hemisphere
(δ≥0°), at high Galactic latitudes (|b|≥ 20°), with
measured redshifts z≤0.3 and fluxes higher than
4.4x10-12erg/cm2/s in the 0.112.4 keV band. The sample, called the
ROSAT Brightest Cluster Sample (BCS), is selected from ROSAT All-Sky
Survey data and is the largest X-ray-selected cluster sample compiled
to date. In addition to Abell clusters, which form the bulk of the
sample, the BCS also contains the X-ray-brightest Zwicky clusters and
other clusters selected from their X-ray properties alone. Effort has
been made to ensure the highest possible completeness of the sample
and the smallest possible contamination by non-cluster X-ray sources.
X-ray fluxes are computed using an algorithm tailored for the
detection and characterization of X-ray emission from galaxy clusters.
These fluxes are accurate to better than 15 per cent (mean 1σ
error).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 119 206 The ROSAT Brightest Cluster Sample
refs.dat 73 47 References
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
J/ApJ/502/558 : Catalog of ROSAT galaxy clusters (Vikhlinin+ 1998)
J/ApJ/514/148 : ROSAT survey of bright galaxies clusters (De Grandi+, 1999)
J/MNRAS/306/857 : ROSAT Brightest Cluster Sample. III. (Crawford+, 1999)
J/MNRAS/318/333 : Extended ROSAT Bright Cluster Sample (Ebeling+ 2000)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- n_Name Note on Name (1)
6- 20 A15 --- Name Cluster name (2)
22- 23 I2 h RAh Right ascension (B1950)
25- 26 I2 min RAm Right ascension (B1950)
28- 31 F4.1 s RAs Right ascension (B1950)
33 A1 --- DE- Declination sign (B1950)
34- 35 I2 deg DEd Declination (B1950)
37- 38 I2 arcmin DEm Declination (B1950)
40- 41 I2 arcsec DEs Declination (B1950)
43- 49 F7.3 deg RAdeg X-ray right ascension (J2000)
51- 57 F7.3 deg DEdeg X-ray declination (J2000)
59- 62 F4.1 10+20cm-2 NH Hydrogen column density from
Stark et al. (1992, Cat. J/ApJS/79/77)
64- 67 I4 s Texp RASS exposition time
69- 73 F5.2 ct/s CR(VTP) PSPC count rate in PHA (Pulse Height Analyser)
channels 11 to 235 originally detected by VTP
(Voronoi tesselation and percolation)
75- 78 F4.1 arcmin R(VTP) Equivalent radius of the source detected by
VTP (Voronoi tesselation and percolation)
80- 85 F6.2 ct/s CR Final PSCP count rate (3)
87- 91 F5.2 ct/s e_CR rms uncertainty on CR (4)
93- 96 F4.1 keV kT Intra-cluster medium gas temperature used in
conversion from count rates to energy fluxes
97 A1 --- n_kT [e] e: temperature estimated
99-103 F5.4 --- z Redshift
105-109 F5.1 10-15W/m2 FX Unabsorbed X-ray energy flux in the
0.1-2.4keV band (10-12erg/cm2/s)
111-116 F6.2 10+37W LX Intrinsic X-ray luminosity in 0.1-2.4keV band
118-119 I2 --- r_z Redshift reference in refs.dat file
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Note (1): Flags:
V = extended according to VTP, Voronoi tesselation and percolation
S = extended according to SASS, Standard Analysis Sofware System
(Vosges et al., 1992, Proc. Satellite Symp. 3, ESA ISY-3, p. 223)
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.
Note (3): Final PSC count rate in PHA channels 11 to 235 based on the original
VTP count rate. Statistical corrections for low-surface brightness
emission that has not been detected directly and for contamination
from point sources have been applied.
Note (4): Error in the final PSPC count rate according to equation
ΔCR/CR=2.29(CR*Texp)-0.48.
The fractional uncertainty in the energy flux and the X-ray luminosity
can be assumed to be the same as the fractional count rate error.
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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 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 49 A26 --- Aut Author's name
51- 73 A23 --- Com Comments
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History:
Provided by H. Andernach, A489 in his list
(End) Francois Ochsenbein [CDS] 28-Jun-2000