J/A+A/461/397 RASS-SDSS galaxy cluster survey. V. (Popesso+, 2007)
RASS-SDSS galaxy cluster survey. V. The X-ray-underluminous Abell clusters.
Popesso P., Biviano A., Boehringer H., Romaniello M.
<Astron. Astrophys., 461, 397-410 (2007)>
=2007A&A...461..397P 2007A&A...461..397P
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Redshifts ; Velocity dispersion
Keywords: galaxies: clusters: general
Abstract:
In this paper we consider a large sample of optically selected
clusters, in order to elucidate the physical reasons for the existence
of X-ray underluminous clusters. For this purpose we analyzed the
correlations of the X-ray and optical properties of a sample of 137
spectroscopically confirmed Abell clusters in the SDSS database. We
searched for the X-ray counterpart of each cluster in the ROSAT All
Sky Survey. We find that 40% of our clusters have a marginal X-ray
detection or remain undetected in X-rays. These clusters appear too
X-ray faint on average for their mass as determined by velocity
dispersion; i.e. they do not follow the scaling relation between X-ray
luminosity and virial mass traced by the other clusters. On the other
hand, they do follow the general scaling relation between optical
luminosity and virial mass. We refer to these clusters as the
X-ray-underluminous Abell clusters (AXU clusters, for short) and
designate as "normal" the X-ray detected Abell systems. We separately
examined the distributions and properties of the galaxy populations of
the normal and the AXU clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 78 137 List the properties of the 137 spectroscopically
confirmed Abell systems extracted from the
SDSS DR3, used in this paper
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See also:
http://www.sdss.org/ : SDSS Home Page
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
II/259 : The SDSS Photometric Catalog, Release 3 (Abazajian+ 2005)
J/A+A/420/61 : RASS/SDSS X-ray clusters of galaxies (Schuecker+, 2004)
J/A+A/423/449 : RASS-SDSS Galaxy Clusters Survey. I. (Popesso+, 2004)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [ACO]
5- 8 I4 --- ACO Name of the Abell cluster
10- 12 I3 --- Nmemb Number of cluster members
within 1 Abell radius
14- 19 F6.4 --- zc Cluster mean redshift
21- 24 I4 km/s sigmac Cluster velocity dispersion
26- 28 I3 km/s e_sigmac rms uncertainty on sigmac
30- 34 F5.2 10+14solMass M200 Cluster mass within r200
36- 40 F5.2 10+14solMass M200r ?=- Cluster mass within r200 calculated
using only the cluster red members
42- 45 F4.2 10+14solMass e_M200 Fractional error on M200 and M200,red
47- 49 F3.1 Mpc r200 Cluster virial radius
51- 55 F5.2 10+12solLum Lopt Cluster optical luminosity
57- 60 F4.2 10+12solLum e_Lopt rms uncertainty on Lopt
62- 66 F5.3 10+41W/m2 LX Cluster X-ray luminosity in the ROSAT
energy band (0.1-2.4keV)
68- 71 F4.2 10+41W/m2 e_LX Fractional error on the X-ray luminosity
73- 76 F4.2 --- PDS Dressler & Shectman (1988AJ.....95..985D 1988AJ.....95..985D)
probability that a cluster does not
contain substructures (1)
78 I1 --- Xcl [0/2] X-ray class (2)
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Note (1): Values <0.1 indicate clusters that are likely to contain substructures
Note (2): X-ray class as follows:
0 = normal X-ray emitting cluster
1 = Abell systems with less the 3σ X-ray detection
2 = X-ray non-detected Abell Clusters
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History:
From electronic version of the journal
References:
Popesso et al., Paper I 2004A&A...423..449P 2004A&A...423..449P, Cat. J/A+A/423/449
Popesso et al., Paper II 2005A&A...433..415P 2005A&A...433..415P
Popesso et al., Paper III 2005A&A...433..431P 2005A&A...433..431P
Popesso et al., Paper IV 2006A&A...445...29P 2006A&A...445...29P
Popesso et al., Paper VI 2007A&A...461..411P 2007A&A...461..411P
Popesso et al., Paper VII 2007A&A...461..451P 2007A&A...461..451P
(End) Patricia Vannier [CDS] 31-Aug-2007