J/ApJ/742/48 Blanco survey of the lens BCS J2352-5452 (Buckley-Geer+, 2011)
The serendipitous observation of a gravitationally lensed galaxy at z = 0.9057
from the Blanco Cosmology Survey: the Elliot Arc.
Buckley-Geer E.J., Lin H., Drabek E.R., Allam S.S., Tucker D.L.,
Armstrong R., Barkhouse W.A., Bertin E., Brodwin M., Desai S.,
Frieman J.A., Hansen S.M., High F.W., Mohr J.J., Lin Y.-T., Ngeow C.-C.,
Rest A., Smith R.C., Song J., Zenteno A.
<Astrophys. J., 742, 48 (2011)>
=2011ApJ...742...48B 2011ApJ...742...48B
ADC_Keywords: Gravitational lensing ; Clusters, galaxy ; Galaxies, spectra ;
Photometry, ugriz ; Redshifts ; Surveys
Keywords: galaxies: high-redshift - gravitational lensing: strong -
gravitational lensing: weak
Abstract:
We report on the serendipitous discovery in the Blanco Cosmology
Survey (BCS) imaging data of a z=0.9057 galaxy that is being strongly
lensed by a massive galaxy cluster at a redshift of z=0.3838. The lens
(BCS J2352-5452) was discovered while examining i- and z-band images
being acquired in 2006 October during a BCS observing run. Follow-up
spectroscopic observations with the Gemini Multi-Object Spectrograph
instrument on the Gemini-South 8m telescope confirmed the lensing
nature of this system. Using weak-plus-strong lensing, velocity
dispersion, cluster richness N200, and fitting to a
Navarro-Frenk-White (NFW) cluster mass density profile, we have made
three independent estimates of the mass M200 which are all very
consistent with each other. The combination of the results from the
three methods gives M200=(5.1±1.3)x1014M☉, which is fully
consistent with the individual measurements. The final NFW
concentration c200 from the combined fit is c200=5.4+1.4-1.1.
We have compared our measurements of M200 and c200 with
predictions for (1) clusters from ΛCDM simulations, (2)
lensing-selected clusters from simulations, and (3) a real sample of
cluster lenses.
Description:
The Blanco Cosmology Survey (BCS) is a 60 night NOAO (National Optical
Astronomy Observatory) imaging survey program (2005-2008), using the
Mosaic-II camera on the Blanco 4m telescope at CTIO (Cerro Tololo
Inter-American Observatory), which has uniformly imaged 75deg2 of
the sky in the SDSS griz bands.
Observations of the lens, which is a rich cluster containing a
prominent central brightest cluster galaxy (BCG), were made with BCS
imaging on 2006 Oct 30 (iz bands), 2006 Dec 14 (gr bands) and 2008 Nov
11 (gr bands) and with Gemini Multi-Object Spectrograph (GMOS) on 2007
Aug 4 and 14.
We obtained GMOS spectra of the source and a number of neighboring
galaxies (Lin et al. 2007, Gemini Proposal GS-2007B-Q-228).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 80 94 Cluster member galaxies
table4.dat 80 12 Other galaxies
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See also:
J/ApJS/193/8 : Spectroscopy of 26 lensing cluster cores (Bayliss+, 2011)
J/ApJS/191/340 : Southern Cosmology Survey. II. (Menanteau+, 2010)
J/MNRAS/404/325 : Massive galaxy clusters lensing analyse (Richard+, 2010)
J/ApJ/682/964 : Sloan lens ACS survey. V. (Bolton+, 2008)
J/ApJS/176/19 : COSMOS: strong lens systems (Faure+, 2008)
J/ApJ/681/1017 : Chandra observations of lens groups (Fassnacht+, 2008)
J/ApJ/668/643 : Multiply imaged gravitational lens systems (Limousin+, 2007)
J/ApJ/660/239 : MaxBCG of 13823 galaxy clusters from SDSS (Koester+, 2007)
J/ApJ/641/169 : Spectroscopy in lens fields (Momcheva+, 2006)
Byte-by-byte Description of file: table3.dat table4.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Mmb "maxBCG" cluster members, "other" cluster
members or "non-mb" (1)
8- 12 I5 --- ID [10692/19588] Object identification number (2)
14- 23 F10.6 deg RAdeg Right ascension in decimal degrees (J2000)
25- 34 F10.6 deg DEdeg Declination in decimal degrees (J2000)
36- 40 F5.2 mag imag SExtractor i-band MAG_AUTO
42- 45 F4.2 mag e_imag imag uncertainty
47- 50 F4.2 mag g-r g-r color index (3)
52- 55 F4.2 mag e_g-r g-r uncertainty (4)
57- 61 F5.2 mag r-i r-i color index (3)
63- 66 F4.2 mag e_r-i r-i uncertainty (4)
68- 73 F6.4 --- z ? Spectroscopic redshift from GMOS
75- 80 F6.4 --- e_z ? z uncertainty
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Note (1): Membership as follows:
maxBCG = Galaxies, with i<21, determined to be cluster members using maxBCG
color selection criteria. Members are also limited to be within a
radius rgal200=1.51h-1Mpc (=6.88') of the brightest cluster
galaxy (BCG). See Section 3.2 for details.
other = Additional galaxies determined to be cluster members via Gemini
Multi-Object Spectrograph (GMOS) spectroscopic redshifts (section 3.3)
but which did not meet the maxBCG color selection criteria (Koester
et al. 2007ApJ...660..221K 2007ApJ...660..221K, 2007, Cat. J/ApJ/660/239).
non-mb = table 4: galaxies determined to be non-cluster members based on
GMOS spectroscopic redshifts (Section 3.3).
Note (2): Object ID numbers are from the SExtractor catalog obtained using the
i-band image for object detection. The objects are ordered from bright
to faint by i-band MAG_AUTO, starting with the brightest cluster
galaxy (BCG).
Note (3): g-r and r-i colors are computed from 3" diameter aperture magnitudes.
Note (4): The errors are simply statistical errors reported by SExtractor. Not
included are photometric calibration errors estimated to be
0.03-0.05mag per filter.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 18-Apr-2013