J/MNRAS/468/1917 Concentration parameter of galaxy clusters (Rossetti+, 2017)
The cool-core state of Planck SZ-selected clusters versus X-ray-selected
samples: evidence for cool-core bias.
Rossetti M., Gastaldello F., Eckert D., Della Torre M., Pantiri G.,
Cazzoletti P., Molendi S.
<Mon. Not. R. Astron. Soc., 468, 1917-1930 (2017)>
=2017MNRAS.468.1917R 2017MNRAS.468.1917R (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Redshifts
Keywords: galaxies: clusters: general - galaxies: clusters: intracluster medium
Abstract:
We characterized the population of galaxy clusters detected with the
Sunyaev-Zeldovich (SZ) effect with Planck by measuring the cool-core
state of the objects in a well-defined subsample of the Planck SZ
catalogue. We used as an indicator the concentration parameter. The
fraction of cool-core clusters is 29±4 per cent and does not show
significant indications of evolution in the redshift range covered by
our sample. We compare the distribution of the concentration parameter
in the Planck sample with the one of the X-ray selected sample MACS:
the distributions are significantly different and the cool-core
fraction in MACS is much higher (59±5 per cent) than that in Planck.
Since X-ray-selected samples are known to be biased towards cool cores
due to the presence of their prominent surface brightness peak, we
simulated the impact of the 'cool-core bias'. We found that this bias
plays a large role in the difference between the fractions of cool
cores in the two samples. We examined other selection effects that
could in principle bias SZ surveys against cool cores, but we found
that their impact is not sufficient to explain the difference between
Planck and MACS. The population of X-ray underluminous objects, which
are found in SZ surveys but missing in X-ray samples, could possibly
contribute to the difference, as we found most of them to be non-cool
cores, but this hypothesis deserves further investigation.
Description:
Properties of the clusters in our Planck (Planck Collaboration et al.,
2014A&A...571A..20P 2014A&A...571A..20P) sample and of the clusters in the ME-MACS (Mann &
Ebeling, 2012MNRAS.420.2120M 2012MNRAS.420.2120M) sample.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 140 169 Properties of the clusters in our Planck sample
table2.dat 86 104 Properties of the clusters in the ME-MACS sample
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See also:
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 name (GLLL.ll+BB.bbb)
25- 41 A17 --- AName Alternative name
43- 44 I2 h RAh X-ray peak right ascension (J2000) (G1)
46- 47 I2 min RAm X-ray peak right ascension (J2000) (G1)
49- 53 F5.2 s RAs X-ray peak right ascension (J2000) (G1)
55 A1 --- DE- X-ray peak declination sign (J2000) (G1)
56- 57 I2 deg DEd X-ray peak declination (J2000) (G1)
59- 60 I2 arcmin DEm X-ray peak declination (J2000) (G1)
62- 66 F5.2 arcsec DEs X-ray peak declination (J2000) (G1)
68- 72 F5.3 --- z Redshift as provided in the catalogue
74- 77 F4.1 10+14Msun M500 Mass as provided in the catalogue
79- 84 F6.4 --- c Concentration parameter
86- 91 F6.4 --- e_c Concentration parameter error
93-140 A48 --- ObsID ID of the observations used in our analysis
(those starting with '0' are data)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Cluater Name
21- 22 I2 h RAh X-ray peak right ascension (J2000) (G1)
24- 25 I2 min RAm X-ray peak right ascension (J2000) (G1)
27- 31 F5.2 s RAs X-ray peak right ascension (J2000) (G1)
33 A1 --- DE- X-ray peak declination sign (J2000) (G1)
34- 35 I2 deg DEd X-ray peak declination (J2000) (G1)
37- 38 I2 arcmin DEm X-ray peak declination (J2000) (G1)
40- 43 F4.1 arcsec DEs X-ray peak declination (J2000) (G1)
45- 48 F4.2 --- z Redshift calculated from the X-ray luminosity
in mannebe
50- 54 F5.2 10+14Msun M500 Mass calculated from the X-ray luminosity
in mannebe
56- 61 F6.4 --- c Concentration parameter
63- 68 F6.4 --- e_c Concentration parameter error
70- 86 A17 --- ObsID ID of the observations used in our analysis
(those starting with '0' are data)
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Global notes:
Note (G1): coordinates of the X-ray peak that we used to measure the
concentration parameter.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 13-Dec-2019