J/A+A/566/A140 Catalog of XMM X-ray galaxy groups (Gozaliasl+, 2014)
Mining the gap: evolution of the magnitude gap in X-ray galaxy groups from the
3-square-degree XMM coverage of CFHTLS.
Gozaliasl G., Finoguenov A., Khosroshahi H.G., Mirkazemi M., Salvato M.,
Jassur D.M.Z., Erfanianfar G., Popesso P., Tanaka M., Lerchster M.,
Kneib J.P., McCracken H.J., Mellier Y., Egami E., Pereira M.J.,
Brimioulle F., Erben T., Seitz S.
<Astron. Astrophys., 566, A140-140 (2014)>
=2014A&A...566A.140G 2014A&A...566A.140G
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Redshifts
Keywords: methods: statistical - techniques: photometric - Galaxy: evolution -
galaxies: clusters: general - galaxies: clusters - X-rays: surveys
Abstract:
We present a catalog of 129 X-ray galaxy groups, covering a redshift
range 0.04<z<1.23, selected in the ∼3deg2 part of the CFHTLS W1
field overlapping XMM observations performed under the XMM-LSS
project. We carry out a statistical study of the redshift evolution
out to redshift one of the magnitude gap between the first and the
second brightest cluster galaxies of a well defined mass-selected
group sample. We find that the slope of the relation between the
fraction of groups and the magnitude gap steepens with redshift,
indicating a larger fraction of fossil groups at lower redshifts. We
find that 22.2±6% of our groups at z≤0.6 are fossil groups. We
compare our results with the predictions of three semi-analytic models
based on the Millennium simulation. The intercept of the relation
between the magnitude of the brightest galaxy and the value of
magnitude gap becomes brighter with increasing redshift. This trend is
steeper than the model predictions which we attribute to the younger
stellar age of the observed brightest cluster galaxies. This trend
argues in favor of stronger evolution of the feedback from active
galactic nuclei at z<1 compared to the models. The slope of the
relation between the magnitude of the brightest cluster galaxy and the
value of the gap does not evolve with redshift and is well reproduced
by the models, indicating that the tidal galaxy stripping, put forward
as an explanation of the occurrence of the magnitude gap, is both a
dominant mechanism and sufficiently well modeled.
Description:
We analysed the XMM-Newton observations of the CFHTLS wide (W1) field
as a part of the XMM-LSS survey (Pierre et al., 2007MNRAS.382..279P 2007MNRAS.382..279P,
Cat. J/MNRAS/382/279). The details of observations and data reduction
are presented in Bielby et al. (2010A&A...523A..66B 2010A&A...523A..66B). We concentrate
on the low-z counterparts of the X-ray sources and use all XMM
observations performed till 2009, covering an area of
2.276°x2.276°.
The CFHTLS wide observations have been carried out in the period
between 2003 and 2008, covering an effective survey area of ∼154
square degrees. The optical images and data of the CFHTLS were
obtained with the MegaPrime instrument mounted on the CFHT in the five
filters u*, g', r', i' and z'.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 131 128 Catalog of XMM X-ray galaxy groups in CFHTLS-W1
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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- 4 A4 --- --- [XMMU]
6- 21 A16 --- XMMU XMMU designation (JHHMMSS.s+DDMMSS)
23- 28 I6 --- Group [100010/103340] Group ID
30- 37 F8.5 deg RAdeg Right ascension of X-ray center (J2000)
38- 46 F9.6 deg DEdeg Declination of X-ray center (J2000)
47- 50 F4.2 --- zph [0.05/1.1] Group photometric redshift
52- 57 F6.3 10+13Msun M200c Total group mass
59- 63 F5.3 10+13Msun e_M200c rms uncertainty on M200c
65- 71 F7.3 10+35W LX X-ray luminosity 0.1-2.4keV (1042erg/s)
73- 78 F6.3 10+35W e_LX rms uncertainty on LX
80- 84 F5.1 km/s sigma Velocity dispersion
86- 91 F6.4 deg R200c [0.01/0.16] Group radius
93- 96 F4.2 keV kT Mean group temperature
98-101 F4.2 keV e_kT rms uncertainty on kT
104-109 F6.3 10-17W/m2 Flux Group X-ray flux in the observed 0.5-2keV
band (in 10-14erg/cm2/s)
111-115 F5.3 10-17W/m2 e_Flux rms uncertainty on Flux
118-122 F5.2 --- Signi Significance of the flux estimate
124 I1 --- Vf [1/5] Visual flag (1)
126-130 F5.3 --- zsp [0.05/1.3]? Group spectroscopic redshift
131 A1 --- n_zsp [*] * for redshifts adopted from Adami et al.
(2011A&A...526A..18A 2011A&A...526A..18A)
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Note (1): Visual flag as follows:
1 = unique X-ray source with a well-defined center, and a unique optical
counterpart with the spectroscopic confirmation
2 = a single X-ray source has been split into several sources
3 = unique X-ray source with a well-defined center, without a unique
optical counterpart with the spectroscopic confirmation
4 = presence of multiple optical counterparts
5 = X-ray emission covers a part of the group area and a concentration of
galaxies is located at the edge of X-ray emission, or
systems with a potentially wrong assignment of optical counterpart
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 15-Oct-2014