J/A+A/555/A30 REFLEX II. Properties of the survey (Boehringer+ 2013)
The ROSAT-ESO Flux Limited X-ray Galaxy Cluster Survey (REFLEX II).
II. Construction and properties of the survey.
Boehringer H., Chon G., Collins C.A., Guzzo L., Nowak N., Bobrovskyi S.
<Astron. Astrophys. 555, A30 (2013)>
=2013A&A...555A..30B 2013A&A...555A..30B
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Surveys ; Redshifts
Keywords: galaxies: clusters: general - large-scale structure of Universe -
X-rays: galaxies: clusters
Abstract:
Galaxy clusters provide unique laboratories to study astrophysical
processes on large scales and are important probes for cosmology.
X-ray observations are currently the best means of detecting and
characterizing galaxy clusters. Therefore X-ray surveys for galaxy
clusters are one of the best ways to obtain a statistical census of
the galaxy cluster population.
In this paper we describe the construction of the REFLEX II galaxy
cluster survey based on the southern part of the ROSAT All-Sky Survey.
REFLEX II extends the REFLEX I survey by a factor of about two down to
a flux limit of 1.8x10-12erg/s/cm2 (0.1-2.4keV).
We describe the determination of the X-ray parameters, the process of
X-ray source identification, and the construction of the survey
selection function.
The REFLEX II cluster sample comprises currently 915 objects. A
standard selection function is derived for a lower source count limit
of 20 photons in addition to the flux limit. The median redshift of
the sample is z=0.102. Internal consistency checks and the comparison
to several other galaxy cluster surveys imply that REFLEX II is better
than 90% complete with a contamination less than 10%.
With this publication we give a comprehensive statistical description
of the REFLEX II survey and provide all the complementary information
necessary for a proper modelling of the survey for astrophysical and
cosmological applications.
Description:
Like REFLEX I, the extended survey covers the southern sky outside the
band of the Milky Way (|bII|≥20°) with regions around the
Magellanic clouds excised (3 in LMC, 3 in SMC). The total survey area
after this excision amounts to 4.24 steradian (or 13924°2) which
corresponds to 33.75% of the sky. Different from REFLEX I, we use the
refined RASS product RASS III (Voges et al. 1999, Cat. IX/10).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 123 151 Count rate to flux conversion (for z=0)
table3.dat 104 20 *K-correction as a function of z and Tx
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Note on table3.dat: The given value is to be multiplied with the luminosity
in the observed band to obtain the luminosity in the rest frame band.
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
J/A+A/499/357 : REFLEX galaxies redshifts (Guzzo+, 2009)
J/A+A/425/367 : REFLEX Galaxy Cluster Survey catalogue (Boehringer+, 2004)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 F7.2 10+20cm-2 NH [0.1/100] Absorbing H column density
11- 17 F7.3 10-14J/m2 CR(0.5keV) Count rate for T=0.5keV (1)
20- 26 F7.3 10-14J/m2 CR(1.0keV) Count rate for T=1.0keV (1)
29- 35 F7.3 10-14J/m2 CR(1.5keV) Count rate for T=1.5keV (1)
38- 44 F7.3 10-14J/m2 CR(2.0keV) Count rate for T=2.0keV (1)
47- 53 F7.3 10-14J/m2 CR(3.0keV) Count rate for T=3.0keV (1)
56- 62 F7.3 10-14J/m2 CR(4.0keV) Count rate for T=4.0keV (1)
65- 71 F7.3 10-14J/m2 CR(5.0keV) Count rate for T=5.0keV (1)
74- 80 F7.3 10-14J/m2 CR(6.0keV) Count rate for T=6.0keV (1)
83- 89 F7.3 10-14J/m2 CR(7.0keV) Count rate for T=7.0keV (1)
92- 98 F7.3 10-14J/m2 CR(8.0keV) Count rate for T=8.0keV (1)
101-107 F7.3 10-14J/m2 CR(9.0keV) Count rate for T=9.0keV (1)
110-116 F7.3 10-14J/m2 CR(10.keV) Count rate for T=10.0keV (1)
119-123 F5.3 --- HR Hardness ratio (H-S)/(H+S) in 0.5-2.0keV
and 0.1-0.4keV bands (2)
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Note (1): Count rate (0.5-2keV) to flux conversion (0.1 to 2.4keV) factors for
different temperatures (for Z=0.3Z☉, z=0) as a function of column
density. The values quoted give the 0.1-2.4keV flux per count in the 0.5 to
2keV band (channel 52 to 201) in units of 10-11erg/cm2/ct.
Note (2): Hardness ratio for an assumed temperature of 5keV, defined as
(counts(0.5-2.0keV)-counts(0.1-0.4keV))/(counts(0.5-2keV)+counts(0.1-0.4keV)).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 F6.4 --- z [0.025/0.5] Redshift
9- 16 F8.4 --- K(0.5keV) K-correction factor for T=0.5keV (1)
17- 24 F8.4 --- K(1.0keV) K-correction factor for T=1.0keV (1)
25- 32 F8.4 --- K(1.5keV) K-correction factor for T=1.5keV (1)
33- 40 F8.4 --- K(2.0keV) K-correction factor for T=2.0keV (1)
41- 48 F8.4 --- K(3.0keV) K-correction factor for T=3.0keV (1)
49- 56 F8.4 --- K(4.0keV) K-correction factor for T=4.0keV (1)
57- 64 F8.4 --- K(5.0keV) K-correction factor for T=5.0keV (1)
65- 72 F8.4 --- K(6.0keV) K-correction factor for T=6.0keV (1)
73- 80 F8.4 --- K(7.0keV) K-correction factor for T=7.0keV (1)
81- 88 F8.4 --- K(8.0keV) K-correction factor for T=8.0keV (1)
89- 96 F8.4 --- K(9.0keV) K-correction factor for T=9.0keV (1)
97-104 F8.4 --- K(10.keV) K-correction factor for T=10.0keV (1)
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Note (1): K-corrections (Ratio of result for z / result for z=0) for
different temperatures and redshift.
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Acknowledgements:
Hans Boehringer and the REFLEX Team, hxb(at)mpe.mpg.de
References:
Chon & Boehringer, Paper I 2012A&A...538A..35C 2012A&A...538A..35C
Chon et al., Paper III 2013MNRAS.429.3272C 2013MNRAS.429.3272C
(End) Hans Boehringer [MPE], Emmanuelle Perret [CDS] 04-Jun-2013