J/MNRAS/437/2607 Low X-ray luminosity galaxy clusters (Nilo Castellon+, 2014)
Low X-ray luminosity galaxy clusters.
II. Optical properties and morphological content at 0.18 < z < 0.70.
Nilo Castellon J.L., Alonso M.V., Lambas D.G., O'Mill A.L., Valotto C.,
Carrasco E.R., Cuevas H., Ramirez A
<Mon. Not. R. Astron. Soc., 437, 2607-2620 (2014)>
=2014MNRAS.437.2607N 2014MNRAS.437.2607N
ADC_Keywords: Clusters, galaxy ; Photometry, SDSS ; Morphology
Keywords: galaxies: clusters: general - galaxies: fundamental parameters -
galaxies: photometry
Abstract:
This is the second of a series of papers on low X-ray luminosity
galaxy clusters, in which we present the r', g' and i' photometry
obtained with Gemini Multi-Object Spectrograph IMAGE at Gemini North
and South telescopes for seven systems in the redshift range of 0.18
to 0.70. Optical magnitudes, colours and morphological parameters,
namely, concentration index, ellipticity and visual morphological
classification, are also given. At lower redshifts, the presence of a
well-defined red cluster sequence extending by more than 4mag showed
that these intermediate-mass clusters had reached a relaxed stage.
This was confirmed by the small fraction of blue galaxy members
observed in the central regions of ∼0.75Mpc. In contrast, galaxy
clusters at higher redshifts had a less important red cluster
sequence. We also found that the galaxy radial density profiles in
these clusters were well fitted by a single power law. At 0.18<z<0.70,
we observed an increasing fraction of blue galaxies and a decreasing
fraction of lenticulars, with the early-type fraction remaining almost
constant. Overall, the results of these intermediate-mass clusters are
in agreement with those for high-mass clusters.
Description:
We selected 19 galaxy clusters from the ROSAT position sensitive
proportional counters pointed observations for this project. These had
X-ray luminosities in the range LX∼0.5-45x1043erg/s, angular core
radius smaller than 60arcsec and redshifts between 0.15 and 0.70 (for
further details, see Paper I, Nilo Castellon et al., 2013, submitted).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 72 7 Low X-ray luminosity galaxy clusters
table3.dat 89 146 Galaxy member properties of the 7 low X-ray
luminosity clusters
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [VMF98] [1/148] Cluster number
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 14 F4.1 s RAs Right ascension (J2000)
16 A1 --- DE- Declination sign (J2000)
17- 18 I2 deg DEd Declination (J2000)
20- 21 I2 arcmin DEm Declination (J2000)
23- 24 I2 arcsec DEs Declination (J2000)
26- 29 F4.1 10+36W LX [1.4/42.7] X-ray luminosity (in 1043erg/s)
31- 35 F5.3 --- z [0.18/0.7] Redshift
37- 51 A15 --- Prog Program ID
53- 54 I2 --- ng [4/15]?=- Number of g'-band exposures
55 A1 --- --- [x]
56- 58 I3 s Tg [300/600]? Individual g'-band exposure time
60- 61 I2 --- nr [4/15]?=- Number of r'-band exposures
62 A1 --- --- [x]
63- 65 I3 s Tr [190/900]? Individual r'-band exposure time
67- 68 I2 --- ni [4/15]?=- Number of i'-band exposures
69 A1 --- --- [x]
70- 72 I3 s Ti [120/150]? Individual i'-band exposure time
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [VMF98] Cluster number
5- 20 A16 --- Gal Galaxy name (JHHMMSS.s+DDMMSS)
22- 23 I2 h RAh Right ascension (J2000)
25- 26 I2 min RAm Right ascension (J2000)
28- 33 F6.3 s RAs Right ascension (J2000)
35 A1 --- DE- Declination sign (J2000)
36- 37 I2 deg DEd Declination (J2000)
39- 40 I2 arcmin DEm Declination (J2000)
42- 47 F6.3 arcsec DEs Declination (J2000)
49- 55 F7.4 mag r'mag [17.7/25.2] Total r' magnitude (AB, fully
corrected by galactic extinction)
57- 63 F7.5 mag r'-i' [0.36/2.76] 2.9"-aperture r'-i' colour index
(AB, fully corrected by galactic extinction)
65- 70 F6.4 --- C [2.1/4.8] Concentration index
73- 78 F6.4 --- b/a [0/1] Ellipticity
80 I1 --- T [1/5] Visual classification (1)
83- 89 F7.5 --- z [0.18/0.8] Redshift (spectroscopic)
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Note (1): Five different morphological types were defined:
1 = Elliptical galaxies: objects having extended and bright halos with a
clear spheroidal morphology and without substructures or asymmetries.
2 = S0/Sa galaxies: extended halos and bright but concentrated cores, and
also included in this type were those galaxies with a clear edge-on
lenticular shape.
3 = Spiral galaxies: objects with clear arms, or/and an extended and tight
edge-on disc with bright cores.
4 = Irregulars: objects having no clear structures
5 = Possible mergers
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History:
From electronic version of the journal and http://www.dfuls.cl/XGClusters
(End) Patricia Vannier [CDS] 07-Jul-2015