J/A+A/614/A82 Cluster candidates for joint X-rays and SZ surveys (Tarrio+, 2018)
A matched filter approach for blind joint detection of galaxy clusters in
X-ray and SZ surveys.
Tarrio P., Melin J.-B., Arnaud M.
<Astron. Astrophys., 614, A82 (2018)>
=2018A&A...614A..82T 2018A&A...614A..82T (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; X-ray sources
Keywords: X-rays: galaxies: clusters
Abstract:
The combination of X-ray and Sunyaev-Zeldovich (SZ) observations can
potentially improve the cluster detection efficiency, when compared to
using only one of these probes, since both probe the same medium, the
hot ionized gas of the intra-cluster medium. We present a method based
on matched multifrequency filters (MMF) for detecting galaxy clusters
from SZ and X-ray surveys. This method builds on a previously proposed
joint X-ray-SZ extraction method and allows the blind detection of
clusters, that is finding new clusters without knowing their position,
size, or redshift, by searching on SZ and X-ray maps simultaneously.
The proposed method is tested using data from the ROSAT all-sky survey
and from the Planck survey. The evaluation is done by comparison with
existing cluster catalogues in the area of the sky covered by the deep
SPT survey. Thanks to the addition of the X-ray information, the joint
detection method is able to achieve simultaneously better purity,
better detection efficiency, and better position accuracy than its
predecessor Planck MMF, which is based on SZ maps alone. For a purity
of 85%, the X-ray-SZ method detects 141 confirmed clusters in the SPT
region; to detect the same number of confirmed clusters with Planck
MMF, we would need to decrease its purity to 70%. We provide a
catalogue of 225 sources selected by the proposed method in the SPT
footprint, with masses ranging between 0.7 and 14.5x1014M☉
and redshifts between 0.01 and 1.2.
Description:
Although the joint algorithm proposed in this paper is a general
technique that can be applied, in principle, to any X-ray and SZ
surveys of the sky, we have tested it in this paper using all-sky maps
from the Planck and RASS surveys.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 141 225 List of candidates for PFA=3.40x10-6,
ordered according to their significance
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See also:
VII/4 : Abell and Zwicky Clusters of Galaxies (Abell+ 1974)
J/A+A/534/A109 : MCXC Meta-Catalogue X-ray galaxy Clusters (Piffaretti+, 2011)
J/ApJS/216/27 : Galaxy clusters discovered in the SPT-SZ survey (Bleem+, 2015)
J/A+A/594/A27 : Planck Sunyaev-Zeldovich sources (PSZ2) (Planck+, 2016)
Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/225] Sequential number
5- 11 F7.3 deg GLON Galactic longitude
13- 19 F7.3 deg GLAT Galactic latitude
21- 27 F7.3 deg RAdeg Right ascension (J2000)
29- 35 F7.3 deg DEdeg Declination (J2000)
37- 42 F6.2 --- (S/N)J Joint S/N
44- 48 F5.2 --- (S/N)sz SZ component of the joint S/N
50- 53 F4.2 --- qJ Joint threshold
55- 60 F6.2 --- (S/N)J-qJ Difference between the S/N and the threshold
62- 66 F5.2 --- Signi Significance, calculated as explained in
Sect. 4
68- 85 A18 --- PSZ2 PSZ2 name (PSZ2 GLLL.ll+BB.bb)
(Cat. J/A+A/594/A27)
87-102 A16 --- SPT SPT name (SPT-CLJHHMM-DDMM)
(Cat. J/ApJS/216/27)
104-119 A16 --- MCXC MCXC name (RXC JHHMM.m+DDMM)
(Cat. J/A+A/534/A109)
121-130 A10 --- Abell Abell name (ABELL NNNN or ACOS NNNN)
(Cat. VII/4)
132-135 F4.2 --- z ? Redshift of the matching cluster (1)
137-141 F5.2 10+14Msun M500 ? Mass estimation using the SZ redshift or
the MCXC redshift (the former is shown if
both are available)
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Note (1): if several are available, we preferentially show the SZ redshift,
then the MCXC redshift, and finally the Abell redshift
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Aug-2018