J/A+A/564/A85 Galaxy properties in clusters. II. (Muriel+, 2014)
Galaxy properties in clusters. II. Backsplash galaxies.
Muriel H., Coenda V.
<Astron. Astrophys., 564, A85-85 (2014)>
=2014A&A...564A..85M 2014A&A...564A..85M
ADC_Keywords: Clusters, galaxy ; X-ray sources; Redshifts; Velocity dispersion
Keywords: galaxies: clusters: general - galaxies: evolution
Abstract:
We explore the properties of galaxies on the outskirts of clusters and
their dependence on recent dynamical history in order to understand
the real impact that the cluster core has on the evolution of
galaxies. We analyse the properties of more than 1000 galaxies
brighter than Mr0.1=-19.6 on the outskirts of 90 clusters
(1<r/rvir<2) in the redshift range 0.05<z<0.10. Using the line of
sight velocity of galaxies relative to the cluster's mean, we selected
low and high velocity subsamples. Theoretical predictions indicate
that a significant fraction of the first subsample should be
backsplash galaxies, that is, objects that have already orbited near
the cluster centre. A significant proportion of the sample of high
relative velocity (HV) galaxies seems to be composed of infalling
objects. Our results suggest that, at fixed stellar mass, late-type
galaxies in the low-velocity (LV) sample are systematically older,
redder, and have formed fewer stars during the last 3Gyrs than
galaxies in the HV sample. This result is consistent with models that
assume that the central regions of clusters are effective in quenching
the star formation by means of processes such as ram pressure
stripping or strangulation. At fixed stellar mass, LV galaxies show
some evidence of having higher surface brightness and smaller size
than HV galaxies. These results are consistent with the scenario where
galaxies that have orbited the central regions of clusters are more
likely to suffer tidal effects, producing loss of mass as well as a
re-distribution of matter towards more compact configurations.
Finally, we found a higher fraction of ET galaxies in the LV sample,
supporting the idea that the central region of clusters of galaxies
may contribute to the transformation of morphological types towards
earlier types.
Description:
In paper I (Coenda & Muriel, 2009A&A...504..347C 2009A&A...504..347C, Cat. J/A+A/504/347),
we selected an X-ray sample of 49 clusters of galaxies from Popesso et
al. (2004A&A...423..449P 2004A&A...423..449P, Cat. J/A+A/423/449, hereafter P04) in the
redshift range 0.05<z<0.14, labelled as C-P04-I. Galaxies in these
clusters were identified using the Main Galaxy Sample (MGS; Strauss et
al. 2002AJ....124.1810S 2002AJ....124.1810S) of the Fifth Data Release (DR5;
Adelman-McCarthy et al. 2007ApJS..172..634A 2007ApJS..172..634A, Cat. II/276) of SDSS,
which includes spectroscopic redshifts down to a Petrosian magnitude
r=17.77. In this paper, we expand the X-ray cluster sample using the
cross-correlation between NORAS and SDSS. We identify a subsample
from Bohringer et al. (2000ApJS..129..435B 2000ApJS..129..435B, Cat. J/ApJS/129/435,
hereafter B00), which we labelled C-B00-I, using the MGS of the
Seventh Data Release (DR7; Abazajian et al. 2009ApJS..182..543A 2009ApJS..182..543A) of
SDSS. This subsample comprises 55 galaxy clusters in the redshift
range 0.05<z<0.14 (the clusters are listed in Table 1).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 55 The C-B00-I cluster sample
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See also:
J/ApJS/129/435 : NORAS galaxy cluster survey. I. (Bohringer+, 2000)
J/A+A/504/347 : Galaxy properties in clusters (Coenda+, 2009)
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right ascension (J2000)
4- 5 I2 min RAm Right ascension (J2000)
7- 10 F4.1 s RAs Right ascension (J2000)
12 A1 --- DE- Declination sign (J2000)
13- 14 I2 deg DEd Declination (J2000)
16- 17 I2 arcmin DEm Declination (J2000)
19- 22 F4.1 arcsec DEs Declination (J2000)
24- 28 F5.3 --- z [0.04/0.18] Redshift
30- 36 F7.2 km/s sigma Velocity dispersion
38- 46 E9.4 Msun Mvir Virial mass (in M☉/h, Ho=70km/s/Mpc)
48- 52 F5.3 Mpc Rvir Virial radius (in Mpc/h)
54- 58 F5.3 Mpc R200 Radius at the mean density of 200 times the
mean density of the universe (in Mpc/h)
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History:
From electronic version of the journal
References:
Coenda & Muriel, Paper I 2009A&A...504..347C 2009A&A...504..347C, Cat. J/A+A/504/347
(End) Patricia Vannier [CDS] 30-Jun-2014