J/ApJS/191/254 GMBCG galaxy cluster catalog from SDSS DR7 (Hao+, 2010)
A GMBCG galaxy cluster catalog of 55,424 rich clusters from SDSS DR7.
Hao J., McKay T.A., Koester B.P., Rykoff E.S., Rozo E., Annis J.,
Wechsler R.H., Evrard A., Siegel S.R., Becker M., Busha M., Gerdes D.,
Johnston D.E., Sheldon E.
<Astrophys. J. Suppl. Ser., 191, 254-274 (2010)>
=2010ApJS..191..254H 2010ApJS..191..254H
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Photometry, SDSS
Keywords: catalogs - galaxies: clusters: general - methods: statistical
Abstract:
We present a large catalog of optically selected galaxy clusters from
the application of a new Gaussian Mixture Brightest Cluster Galaxy
(GMBCG) algorithm to SDSS Data Release 7 data. The algorithm detects
clusters by identifying the red-sequence plus brightest cluster galaxy
(BCG) feature, which is unique for galaxy clusters and does not exist
among field galaxies. Red-sequence clustering in color space is
detected using an Error Corrected Gaussian Mixture Model. We run GMBCG
on 8240 deg2 of photometric data from SDSS DR7 to assemble the
largest ever optical galaxy cluster catalog, consisting of over 55,000
rich clusters across the redshift range from 0.1<z<0.55. We present
Monte Carlo tests of completeness and purity and perform
cross-matching with X-ray clusters and with the maxBCG sample at low
redshift. These tests indicate high completeness and purity across the
full redshift range for clusters with 15 or more members.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
gmbcgdr7.dat 195 55424 Catalog of BCGs in rich clusters of galaxies from
GMBCG (Gaussian Mixture Brightest Cluster Galaxy)
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
http://home.fnal.gov/~jghao/gmbcg_sdss_catalog.html : GMBCG Home Page
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: gmbcgdr7.dat
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Bytes Format Units Label Explanations
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1- 18 I18 --- objid Unique ID of each galaxy in SDSS DR7
20- 28 F9.5 deg RAdeg Right ascension (J2000)
30- 39 F10.6 deg DEdeg Declination (J2000)
41- 45 F5.3 --- zph Photometric redshift from DR7 photo-z table
47- 51 F5.3 --- e_zph Error of zph
53- 59 F7.5 --- zsp Spectroscopic redshift
61- 65 F5.3 mag g-r SDSS g-r colour index (1)
67- 71 F5.3 mag e_g-r Error of g-r
73- 77 F5.3 mag r-i SDSS r-i colour index (1)
79- 83 F5.3 mag e_r-i Error of r-i
85- 90 F6.3 mag umag Dust extinction corrected model u magnitude (2)
92- 97 F6.3 mag gmag Dust extinction corrected model g magnitude (2)
99-104 F6.3 mag rmag Dust extinction corrected model r magnitude (2)
106-111 F6.3 mag imag Dust extinction corrected model i magnitude (2)
113-118 F6.3 mag zmag Dust extinction corrected model z magnitude (2)
120-124 F5.3 mag e_umag Error on umag
126-130 F5.3 mag e_gmag Error on gmag
132-136 F5.3 mag e_rmag Error on rmag
138-142 F5.3 mag e_imag Error on imag
144-148 F5.3 mag e_zmag Error on zmag
150-155 F6.3 --- Scl [5/67] Clustering strength (3)
157-159 I3 --- Ng [8/143] Number of member galaxies inside
GMSCALEDR from BCG (GMSCALEDNGALS)
161-167 F7.3 --- Ng.W [0/134] Weighted richness (GMNGALSWEIGHTED)
169 I1 --- q_Ng.W [0/1] If it is set to 1, we recommend the use
of Ng.W for this cluster
171-175 A5 --- --- [GMBCG]
177-195 A19 --- GMBCG GMBCG designation, JDDD.ddddd+DD.ddddd
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Note (1): All colors are calculated using model magnitude.
Note (2): For details, see http://www.sdss.org/DR7/algorithms/photometry.html
Note (3): the clustering strength parameter is essentially the height of
the peak of the smoothed red-sequence density field at the position of
the BCG. See section 3.5 for details.
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History:
Copied at http://home.fnal.gov/~jghao/gmbcg_sdss_catalog.html
(End) Patricia Vannier [CDS] 19-Aug-2013