J/MNRAS/457/4515 X-ray_peak-BCG offset for PSZ1 clusters (Rossetti+, 2016)
Measuring the dynamical state of Planck SZ-selected clusters:
X-ray peak - BCG offset.
Rossetti M., Gastaldello F., Ferioli G., Bersanelli M., De Grandi S.,
Eckert D., Ghizzardi S., Maino D., Molendi S.
<Mon. Not. R. Astron. Soc., 457, 4515-4524 (2016)>
=2016MNRAS.457.4515R 2016MNRAS.457.4515R (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; X-ray sources
Keywords: galaxies: clusters: general - galaxies: clusters: intracluster medium
Abstract:
We want to characterize the dynamical state of galaxy clusters
detected with the Sunyaev-Zeldovich (SZ) effect by Planck and
compare them with the dynamical state of clusters selected in X-rays
survey. We analysed a representative subsample of the Planck SZ
catalogue, containing the 132 clusters with the highest signal to
noise ratio and characterize their dynamical state using as an
indicator the projected offset between the peak of the X-ray emission
and the position of the Brightest cluster galaxy. We compare the
distribution of this indicator for the Planck SZ-selected sample and
three X-ray-selected samples (HIFLUGCS, MACS and REXCESS). The
distributions are significantly different and the fraction of relaxed
objects is smaller in the Planck sample (52±4 per cent) than in X-ray
samples (~=74 per cent) We interpret this result as an indication of
different selection effects affecting X-rays (e.g. 'cool core
bias') and SZ surveys of galaxy clusters.
Description:
The starting point of our analysis is the Planck cosmology sample
(PSZ1-cosmo) described in Planck Collaboration XX
(2014A&A...571A..20P 2014A&A...571A..20P).
It is a high-purity subsample constructed from the first release of
the Planck catalogue of SZ sources (Planck Collaboration XXIX,
2014A&A...571A..29P 2014A&A...571A..29P, Cat. VIII/91), by imposing a signal-to-noise
ratio (S/N) threshold of 7 and applying a mask, that excludes the
galactic plane and point sources leaving 65 per cent of the sky
for the survey. It contains 189 bona fide clusters with associated
redshifts and has been used for the cosmological analysis with cluster
number counts described in Planck Collaboration XX
(2014A&A...571A..20P 2014A&A...571A..20P).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 128 132 Properties of the clusters in our sample
refs.dat 76 28 References
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See also:
VIII/91 : Planck Catalog of Compact Sources Release 1 (Planck, 2013)
J/A+A/581/A14 : Updated Planck catalogue PSZ1 (Planck+, 2015)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Index Index in the PSZ1 catalogue
6- 9 A4 --- --- [PSZ1]
11- 23 A13 --- PSZ1 PSZ1 designation (GLLL.ll+BB.bb)
25- 41 A17 --- AName Alternative name
43- 48 F6.4 --- z Redshift of the cluster
50- 57 F8.4 deg RAdeg X-ray peak right ascension (J2000)
59- 66 F8.4 deg DEdeg X-ray peak declination (J2000)
68- 75 F8.4 deg RABdeg BCG right ascension (J2000)
78- 85 F8.4 deg DEBdeg BCG peak declination (J2000)
88-100 A13 --- Ref Reference we used to associate a BCG to each
cluster, in refs.dat file
102-106 F5.2 arcmin theta500 Angular scale corresponding to R500
108-114 F7.2 arcsec DX-BCGa Distance between X-ray peak and BCG in arcsec
116-122 F7.2 kpc DX-BCGk Distance between X-ray peak and BCG in kpc
123-128 F6.2 --- DX-BCGR Distance between X-ray peak and BCG in
0.01R500 unit
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Ref Reference code
15- 33 A19 --- BibCode BibCode
35- 51 A17 --- Aut Author's name
56- 76 A21 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 24-Nov-2016