J/ApJ/748/56 K2-detected clusters in the CFHTLS-W1 field (Shan+, 2012)
Weak lensing measurement of galaxy clusters in the CFHTLS-Wide survey.
Shan H.Y., Kneib J.-P., Tao C., Fan Z., Jauzac M., Limousin M., Massey R.,
Rhodes J., Thanjavur K., McCracken H.J.
<Astrophys. J., 748, 56 (2012)>
=2012ApJ...748...56S 2012ApJ...748...56S
ADC_Keywords: Clusters, galaxy ; Surveys ; Redshifts
Keywords: cosmology: observations - galaxies: clusters: general -
gravitational lensing: weak - X-rays: galaxies: clusters
Abstract:
We present the first weak gravitational lensing analysis of the
completed Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). We
study the 64 deg2 W1 field, the largest of the CFHTLS-Wide survey
fields, and present the largest contiguous weak lensing convergence
"mass map" yet made. 2.66 million galaxy shapes are measured, using
the Kaiser Squires and Broadhurst Method (KSB) pipeline verified
against high-resolution Hubble Space Telescope imaging that covers
part of the CFHTLS. Our i'-band measurements are also consistent with
an analysis of independent r'-band imaging. The reconstructed lensing
convergence map contains 301 peaks with signal-to-noise ratio
ν>3.5, consistent with predictions of a ΛCDM model. Of these
peaks, 126 lie within 3.0' of a brightest central galaxy identified
from multicolor optical imaging in an independent, red sequence
survey. We also identify seven counterparts for massive clusters
previously seen in X-ray emission within 6 deg2 XMM-LSS survey. With
photometric redshift estimates for the source galaxies, we use a
tomographic lensing method to fit the redshift and mass of each
convergence peak. Matching these to the optical observations, we
confirm 85 groups/clusters with χ2reduced<3.0, at a mean
redshift <zc≥0.36 and velocity dispersion <σc≥658.8km/s.
Future surveys, such as DES, LSST, KDUST, and EUCLID, will be able to
apply these techniques to map clusters in much larger volumes and thus
tightly constrain cosmological models.
Description:
We analyze the CFHT Legacy Survey Wide imaging from the Terapix T0006
processing run, which is the first to include the complete survey and
was publicly released on 2010 November 15 (Goranova et al. 2009,
http://terapix.iap.fr/cplt/T0006-doc.pdf). The survey used most of
the telescope dark and gray time from 2003 to 2008. These data cover
∼171deg2 in four fields (W1, W2, W3, and W4) of which the
72-pointing, ∼64deg2 W1 field is the largest, and in five passbands
(u', g', r', i', and z') down to i∼24.5 and r∼25.0.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 167 126 Catalog of the matching groups/clusters between
ν>3.5 convergence peaks and K2-detected
groups/clusters in CFHTLS-Wide W1 fields
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See also:
B/cfht : Log of CFHT Exposures (CADC, 1979-)
II/317 : The CFHTLS Survey (T0007 release) (Hudelot+ 2012)
J/A+A/551/A8 : Gal. clusters in XMM field within CFHT-LS D4 (de Hoon+, 2013)
J/A+A/546/A79 : 400d Cluster Survey Weak Lensing Programme II (Israel+ 2012)
J/A+A/535/A65 : Galaxy clusters in the 4 CFHTLS Wide fields (Durret+, 2011)
J/MNRAS/413/1145 : Galaxy clusters in the COSMOS field (Bellagamba+, 2011)
J/A+A/509/A81 : Candidate clusters detected in 6 CFHTLS fields (Adami+, 2010)
J/A+A/494/845 : Galaxy clusters in the CFHTLS (Grove+, 2009)
J/ApJ/703/2232 : Weak lensing of SDSS galaxy clusters. III. (Sheldon+, 2009)
J/ApJ/703/2217 : Lensing measurement of SDSS gal. clusters. I. (Sheldon+, 2009)
J/A+A/461/81 : Galaxy clusters in the CFHTLS (Olsen+, 2007)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- ID Cluster candidate identification (c[1-126]-w1)
9- 14 F6.2 --- zK2 [0.02/0.81]?=-99 K2 redshift (1)
16- 21 F6.3 deg RAK2deg K2 right ascension (J2000)
23- 29 F7.3 deg DEK2deg K2 declination (J2000)
31- 35 F5.2 --- S(r-i) [3/23] K2 detection significance (r-i)
37- 42 F6.3 deg RAdeg CFHTLS Right ascension (J2000)
44- 50 F7.3 deg DEdeg CFHTLS Declination (J2000)
52- 58 F7.3 arcsec Dist [1/180] Separation between K2 and CFHTLS
source
60- 63 F4.2 --- zSIS [0.06/0.88] Singular isothermal sphere (SIS)
model redshift (2)
65- 68 F4.2 --- E_zSIS [0.04/3.2] Positive error on zSIS
70- 73 F4.2 --- e_zSIS [0.05/0.8] Negative error on zSIS
75 A1 --- u_Sig [~] Uncertainty flag on Sig
77- 82 F6.1 km/s Sig Cluster velocity dispersion (σv)
84- 88 F5.1 km/s E_Sig ? Positive error on Sig
90- 94 F5.1 km/s e_Sig ? Negative error on Sig
96- 99 F4.2 --- chi2SIS SIS model χ2
101-104 F4.2 --- zNFW [0.07/0.88] NFW model redshift (2)
106-109 F4.2 --- E_zNFW Positive error on zNFW
111-114 F4.2 --- e_zNFW Negative error on zNFW
116 A1 --- u_mNFW [~] Uncertainty flag on mNFW
118-123 F6.2 10+14Msun mNFW [0/47] NFW model mass
in units of 1014M☉h-1
125-130 F6.2 10+14Msun E_mNFW ? Positive error on mNFW
132-135 F4.2 10+14Msun e_mNFW ? Negative error on mNFW
137 A1 --- l_m200 [~] Uncertainty flag on m200
139-144 F6.2 10+14Msun m200 [0/39] mass M200 enclosed within a radius
r200 in units of 1014M☉h-1
146-151 F6.2 10+14Msun E_m200 ? Positive error on m200
153-156 F4.2 10+14Msun e_m200 ? Negative error on m200
158-161 F4.2 --- chi2NFW NFW model χ2
163-167 F5.3 --- nu [3.5/6.5] Convergence peak ν
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Note (1): K2 redshift denotes the median redshift of bright (i≤20) cluster
members. To identify counterparts of the weak lensing peaks, we match
our cluster candidates to the K2 galaxy cluster catalog, created using
photometric redshift estimates across the CFHTLS-Wide W1 field
(Thanjavur et al. 2009ApJ...706..571T 2009ApJ...706..571T). Of the 301 peaks with ν>3.5,
126 have a corresponding optically detected BCG within 3.0'.
Note (2): We fit the 3D shear signal around each cluster candidate
to both a singular isothermal sphere (SIS) and a Navarro et al.
(1996ApJ...462..563N 1996ApJ...462..563N; NFW) model, with the cluster lens as an
additional free parameter. See section 6 for further explanations.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 10-Oct-2013