J/MNRAS/497/5485 Dynamical state for 964 galaxy clusters (Yuan+, 2020)
Dynamical state for 964 galaxy clusters from Chandra X-ray images.
Yuan Z.S., Han J.L.
<Mon. Not. R. Astron. Soc., 497, 5485-5497 (2020)>
=2020MNRAS.497.5485Y 2020MNRAS.497.5485Y (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Positional data ; Redshifts
Keywords: galaxies: clusters: general - galaxies: clusters: intracluster medium
Abstract:
The dynamical state of galaxy clusters describes if clusters are
relaxed dynamically or in a merging process of subclusters. Using
archival images from the Chandra X-ray Observatory, we derive a set of
parameters to describe the dynamical state for 964 galaxy clusters.
Three widely used indicators for dynamical state, the concentration
index c, the centroid shift ω, and the power ratio P3/P0 are
calculated in the circular central region with a radius of 500kpc. We
also derive two adaptive parameters, the profile parameter κ and
the asymmetry factor α, in the best fitted elliptical region.
The morphology index δ is then defined by combining these two
adaptive parameters, which indicates the dynamical state of galaxy
clusters and has good correlations to the concentration index c, the
centroid shift ω, the power ratio P3/P0, and the optical
relaxation factor Γ. For a large sample of clusters, the
dynamical parameters are continuously distributed from the disturbed
to relaxed states with a peak in the between, rather than the bimodal
distribution for the two states. We find that the newly derived
morphology index δ works for the similar fundamental plane
between the radio power, cluster mass, and the dynamical state for
clusters with diffuse radio giant-haloes and mini-haloes. The offset
between masses estimated from the Sunyaev-Zeldovich effect and X-ray
images depends on dynamical parameters. All dynamical parameters for
galaxy clusters derived from the Chandra archival images are available
on http://zmtt.bao.ac.cn/galaxy_clusters/dyXimages/.
Description:
We collect the observation information for clusters of galaxies
archived by the Chandra in two approaches.
First, we get the information for all observations which categorized
as 'Clusters of galaxies' in the Chandra archival database
(http://cda.harvard.edu/chaser/). As a result, more than 2000
observations are obtained, often several observations are made for one
cluster. For clusters observed more than one time, we generally choose
the observation with largest photon number. However, we select the
observation for nearby clusters (mostly with z<0.05) not only with a
sufficient photon number but also with a good coverage of CCDs. After
removing reduplicate observations, we obtained data for 915 clusters.
Secondly, we cross-match several widely used cluster catalogues: the
Abell (Abell, Corwin & Olowin 1989ApJS...70....1A 1989ApJS...70....1A, Cat. VII/110A),
MCXC (Piffaretti et al. 2011A&A...534A.109P 2011A&A...534A.109P, Cat. J/A+A/534/A109),
redMaPPer (Rykoff et al. 2014ApJ...785..104R 2014ApJ...785..104R, Cat. J/ApJ/785/104),
CAMIRA (Oguri 2014MNRAS.444..147O 2014MNRAS.444..147O, Cat. J/MNRAS/444/147), WH15 (Wen,
Han & Liu 2012ApJS..199...34W 2012ApJS..199...34W, Cat. J/ApJS/199/34; Wen & Han
2015MNRAS.448....2W 2015MNRAS.448....2W), and WHY18 (Wen, Han & Yang 2018MNRAS.475..343W 2018MNRAS.475..343W,
Cat. J/MNRAS/475/343), with archived Chandra observations to find
serendipitous observed clusters.
In total, we have a sample of 964 galaxy clusters with good Chandra
X-ray image data (see Table 1).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 116 964 Dynamical parameters for 964 galaxy clusters
table2.dat 115 125 Dynamical parameters for 125 clusters with known
dynamical states from literature
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See also:
IX/57 : The Chandra Source Catalog (CSC), Release 2.0 (Evans+, 2019)
VII/110A : Rich Clusters of Galaxies (Abell+ 1989)
J/A+A/534/A109 : MCXC Meta-Catalogue X-ray galaxy Clusters
(Piffaretti+, 2011)
J/ApJ/785/104 : redMaPPer. I. Algorithm applied to SDSS DR8 (Rykoff+, 2014)
J/MNRAS/444/147 : Richness of galaxy clusters (Oguri, 2014)
J/ApJS/199/34 : Clusters of galaxies in SDSS-III (Wen+, 2012)
J/MNRAS/475/343 : 2MASS, WISE, and SuperCOSMOS clusters of galaxies
(Wen+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Galaxy cluster name
22 A1 --- f_Name [*] Flag on Name (1)
24- 29 I6 --- ID Chandra observation ID
31- 39 F9.5 deg RAdeg Right ascension (J2000)
41- 49 F9.5 deg DEdeg Declination (J2000)
51- 56 F6.4 --- z ?=9.9999 Redshift
58- 62 F5.2 [-] logc ? Logarithm of the concentration index (2)
64- 67 F4.2 [-] e_logc ? Error on logc (2)
69- 73 F5.2 [-] logw ? Logarithm of the centroid shift (2)
75- 78 F4.2 [-] e_logw ? Error on logw (2)
80- 84 F5.2 [-] logP3/P0 ? Logarithm of the power ratio (2)
86- 89 F4.2 [-] e_logP3/P0 ? Error on logP3/P0 (2)
91- 95 F5.2 [-] logalpha Logarithm of the asymmetry factor (G1)
97- 100 F4.2 [-] e_logalpha Error on logalpha
102- 105 F4.2 --- kappa Profile parameter (G2)
107- 111 F5.2 --- delta Morphology index (G3)
113- 116 F4.2 --- e_delta Error on delta
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Note (1): Flag as follows:
* = Very close cluster with z<0.01. The X-ray images of these clusters are
smoothed to 10kpc.
Note (2): An empty value means the concentration index, the centroid shift and
the power ratio of the cluster could not be calculated since:
(1) the redshift was not available, or (2) the cluster is so close
(mostly z<0.05) that the angular size of the aperture with radius of
500kpc is out of the coverage of Chandra CCD significantly
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Galaxy cluster name
18 A1 --- f_Name [*] Flag on Name (1)
20- 24 I5 --- ID Chandra observation ID
26- 34 F9.5 deg RAdeg Right ascension (J2000)
36- 44 F9.5 deg DEdeg Declination (J2000)
46- 51 F6.4 --- z Redshift
53- 57 F5.2 [-] logc Logarithm of the concentration index
59- 62 F4.2 [-] e_logc Error on logc
64- 68 F5.2 [-] logw Logarithm of the centroid shift
70- 73 F4.2 [-] e_logw Error on logw
75- 79 F5.2 [-] logP3/P0 Logarithm of the power ratio
81- 84 F4.2 [-] e_logP3/P0 Error on logP3/P0
86- 89 F4.2 --- kappa Profile parameter (G2)
91- 95 F5.2 [-] logalpha Logarithm of the asymmetry factor (G1)
97- 100 F4.2 [-] e_logalpha Error on logalpha
102- 106 F5.2 --- delta Morphology index (G3)
108- 111 F4.2 --- e_delta Error on delta
113 A1 --- State [RD] Dynamical state (2)
115 A1 --- fdyn Dynamical flag classified by Mann & Ebeling
(2012MNRAS.420.2120M 2012MNRAS.420.2120M)
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Note (1): Flag as follows:
* = Cluster selected from the BCS and eBCS catalogue (Ebeling et al.
1998MNRAS.301..881E 1998MNRAS.301..881E, Cat. J/MNRAS/301/881; 2000MNRAS.318..333E 2000MNRAS.318..333E, Cat.
J/MNRAS/318/333) with the same selection criteria used by Mann & Ebeling
(2012MNRAS.420.2120M 2012MNRAS.420.2120M), and dynamically categorized by us with the
standard in Mann & Ebeling (2012MNRAS.420.2120M 2012MNRAS.420.2120M).
Note (2): State as follows:
R = Relaxed cluster (57/125)
D = Disturbed cluster (68/125)
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Global Notes:
Note (G1): Asymmetry factor α defined by equation (11) of the article
(see Section 3.2.2)
Note (G2): We define a new profile parameter κ for the brightness
distribution as being: κ=(1+ε)/β
Here, β and ε are the power-law index and the
ellipticity for the fitted β-model
Note (G3): Because the dynamical state cannot be represented with a single
parameter and an easy threshold, the combination of the profile
parameter κ and the asymmetry factor α can indicate the
dynamical state of galaxy clusters more properly. Here, we define
the morphology index δ as being δ=Aκ+Bα+C.
A, B and C are determined by studying the test sample.
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 27-Jul-2023