J/A+A/535/A65 Galaxy clusters in the 4 CFHTLS Wide fields (Durret+, 2011)
Galaxy cluster searches based on photometric redshifts in the four CFHTLS
Wide fields.
Durret F., Adami C., Cappi A., Maurogordato S., Marquez I., Ilbert O.,
Coupon J., Arnouts S., Benoist C., Blaizot J., Edorh T.M., Garilli B.,
Guennou L., Le Brun V., Le Fevre O., Mazure A., McCracken H.J., Mellier Y.,
Mezrag C., Slezak E., Tresse L., Ulmer M.P.
<Astron. Astrophys. 535, A65 (2011)>
=2011A&A...535A..65D 2011A&A...535A..65D
ADC_Keywords: Clusters, galaxy ; Redshifts
Keywords: large-scale structure of Universe - galaxies: clusters: general -
surveys
Abstract:
We have developed a method for detecting clusters in large imaging
surveys, based on the detection of structures in galaxy density maps
made in slices of photometric redshifts. This method was first applied
to the Canada France Hawaii Telescope Legacy Survey (CFHTLS) Deep 1
field by Mazure et al. (2007A&A...467...49M 2007A&A...467...49M), then to all the Deep and
Wide CFHTLS fields available in the T0004 data release by Adami et al.
(2010, Cat. J/A+A/509/81). The validity of the cluster detection rate
was estimated by applying the same procedure to galaxies from the
Millennium simulation. Here we analyse with the same method the full
CFHTLS Wide survey, based on the T0006 data release. In a total area
of 154deg2, we have detected 4061 candidate clusters at 3sigma or
above (6802 at 2sigma and above), in the redshift range 0.1≤z≤1.15,
with estimated mean masses between 1.3x1014 and 12.6x1014M☉.
We compare our detections with those made in various CFHTLS analyses
with other methods. By stacking a subsample of clusters, we show that
this subsample has typical cluster characteristics (colour-magnitude
relation, galaxy luminosity function). We also confirm that the
cluster-cluster correlation function is comparable to that obtained
for other cluster surveys and analyze large scale filamentary galaxy
distributions. We have increased the number of known optical high
redshift cluster candidates by a large factor, an important step
towards obtaining reliable cluster counts to measure cosmological
parameters. The clusters that we detect behave as expected for a
sample of clusters fed by filaments at the intersection of which they
are located.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
wide1.dat 32 3247 Cluster positions and magnitudes in Wide 1
wide2.dat 32 919 Cluster positions and magnitudes in Wide 2
wide3.dat 32 1819 Cluster positions and magnitudes in Wide 3
wide4.dat 32 817 Cluster positions and magnitudes in Wide 4
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See also:
J/A+A/509/A81 : Candidate clusters detected in six CFHTLS fields (Adami+, 2010)
Byte-by-byte Description of file: wide1.dat wide2.dat wide3.dat wide4.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Field [W1234] Field name (W1-W4)
3 A1 --- --- [-]
4- 7 I4 --- Seq Running number within the field
9- 16 F8.4 deg RAdeg Right ascension in decimal degrees (J2000.0)
18- 25 F8.4 deg DEdeg Declination in decimal degrees (J2000.0)
27- 30 F4.2 --- zphot Photometric redshift
32 I1 --- S/N Signal to noise or significance level
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Acknowledgements:
Florence Durret, durret(at)iap.fr
(End) Patricia Vannier [CDS] 13-Sep-2011