J/ApJS/232/15 Candidate strong lens systems from DES obs. (Diehl+, 2017)
The DES Bright Arcs Survey: hundreds of candidate strongly lensed galaxy systems
from the Dark Energy Survey Science Verification and Year 1 observations.
Diehl H.T., Buckley-Geer E.J., Lindgren K.A., Nord B., Gaitsch H.,
Gaitsch S., Lin H., Allam S., Collett T.E., Furlanetto C., Gill M.S.S.,
More A., Nightingale J., Odden C., Pellico A., Tucker D.L., da Costa L.N.,
Neto A.F., Kuropatkin N., Soares-Santos M., Welch B., Zhang Y.,
Frieman J.A., Abdalla F.B., Annis J., Benoit-Levy A., Bertin E., Brooks D.,
Burke D.L., Rosell A.C., Kind M.C., Carretero J., Cunha C.E.,
D'Andrea C.B., Desai S., Dietrich J.P., Drlica-Wagner A., Evrard A.E.,
Finley D.A., Flaugher B., Garcia-Bellido J., Gerdes D.W., Goldstein D.A.,
Gruen D., Gruendl R.A., Gschwend J., Gutierrez G., James D.J., Kuehn K.,
Kuhlmann S., Lahav O., Li T.S., Lima M., Maia M.A.G., Marshall J.L.,
Menanteau F., Miquel R., Nichol R.C., Nugent P., Ogando R.L.C.,
Plazas A.A., Reil K., Romer A.K., Sako M., Sanchez E., Santiago B.,
Scarpine V., Schindler R., Schubnell M., Sevilla-Noarbe I., Sheldon E.,
Smith M., Sobreira F., Suchyta E., Swanson M.E.C., Tarle G., Thomas D.,
Walker A.R., (the DES Collaboration)
<Astrophys. J. Suppl. Ser., 232, 15-15 (2017)>
=2017ApJS..232...15D 2017ApJS..232...15D (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing ; Galaxies, photometry ; Redshifts ; Surveys
Keywords: galaxies: high-redshift; gravitational lensing: strong
Abstract:
We report the results of searches for strong gravitational lens
systems in the Dark Energy Survey (DES) Science Verification and Year1
observations. The Science Verification data span approximately
250°2 with a median i-band limiting magnitude for extended
objects (10σ) of 23.0. The Year 1 data span approximately
2000°2 and have an i-band limiting magnitude for extended
objects (10σ) of 22.9. As these data sets are both wide and
deep, they are particularly useful for identifying strong
gravitational lens candidates. Potential strong gravitational lens
candidate systems were initially identified based on a color and
magnitude selection in the DES object catalogs or because the system
is at the location of a previously identified galaxy cluster. Cutout
images of potential candidates were then visually scanned using an
object viewer and numerically ranked according to whether or not we
judged them to be likely strong gravitational lens systems. Having
scanned nearly 400000 cutouts, we present 374 candidate strong lens
systems, of which 348 are identified for the first time. We provide
the R.A. and decl., the magnitudes and photometric properties of the
lens and source objects, and the distance (radius) of the source(s)
from the lens center for each system.
Description:
The Dark Energy Survey (DES) is in the midst of imaging 5000°2
of the southern galactic cap using the Dark Energy Camera (DECam),
which is operated on the 4m Victor M. Blanco Telescope at Cerro
Tololo Interamerican Observatory (CTIO) near La Serena, Chile.
Science verification (SV) spanned 79 nights or half-nights from 2012
November 1, to 2013 February 22. The main SV wide-field (WF) survey
areas amounted to ∼250°2 at non-uniform depth and data quality.
The first full observing season, Year 1 (Y1), spanned 119 nights or
half-nights from 2013 August 31 to 2014 February 9. The Y1 wide-field
(WF) survey observations were concentrated in two areas: one of about
150°2 near the celestial equator that included a part of SDSS
Stripe 82 (Annis+ 2014ApJ...794..120A 2014ApJ...794..120A), and a much larger region of
roughly 1800°2 from -60° to -40° decl. that overlapped
the area mapped in microwaves by the South Pole Telescope (SPT).
Generally, we observed those fields four times in each of the five
filters: the g, r, i, z, and Y-bands.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 89 376 Properties of candidate lensing systems
table3.dat 104 1091 *Names, positions, photometry, and photometric
redshifts of objects for each candidate
lensing system
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Note on table3.dat: The data were processed by the Dark Energy Survey Data
Management (DESDM) system (Mohr+ 2012SPIE.8451E..0DM ; R. Gruendl+ 2017,
in preparation) in three pipelined stages: single-epoch "detrending",
photometric calibration, and coaddition.
See section 2 for further explanations.
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See also:
J/ApJS/176/19 : COSMOS: strong lens systems (Faure+, 2008)
J/ApJS/191/340 : Southern Cosmology Survey. II. (Menanteau+, 2010)
J/ApJS/193/8 : Spectroscopy of 26 lensing cluster cores (Bayliss+, 2011)
J/ApJ/742/48 : Blanco survey of the lens BCS J2352-5452 (Buckley-Geer+, 2011)
J/ApJ/749/38 : CFHTLS-SL2S-ARCS strong lens candidates (More+, 2012)
J/ApJ/761/22 : NIR galaxy cluster candidates in the SPT survey (Song+, 2012)
J/ApJ/763/127 : Galaxy clusters discovered in SPT survey (Reichardt+, 2013)
J/ApJ/785/144 : SL2S galaxy-scale sample of lens candidates (Gavazzi+, 2014)
J/ApJS/216/27 : Galaxy clusters discovered in the SPT-SZ survey (Bleem+, 2015)
J/A+A/592/A75 : New lens candidates in CFHTLS (Paraficz+, 2016)
J/ApJ/816/98 : Galaxies in X-ray clusters with DES. I. (Zhang+, 2016)
http://admin.masterlens.org/index.php : Master Lens Database
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [DES]
4- 13 A10 --- DES System identifier (JHHMM+DDMM)
ordered by increasing RA
15- 37 A23 --- Al Algorithm(s) that detected the system (1)
39- 40 I2 --- Rank [3/10]? Visual inspection rank (3=lowest to
10=definite strong lens system)
42- 46 F5.2 arcsec Rad [1.3/35] Average radius
48- 51 F4.2 arcsec e_Rad [0.2/9] Uncertainty in Rad
53- 56 A4 --- Mult Source objects that are multiply imaged
58- 81 A24 --- OName Reference to detections in other paper(s) (2)
83- 89 A7 --- r_OName Reference(s) for other detection (3)
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Note (1): Algorithm as follows:
BNA = "Blue Near Anything" (BNA) 2+ (section 3.2);
1K = "Blue Near Anything" (BNA) 1K (section 3.2);
RedM = redMaPPer clusters and redMaGiC galaxies (section 3.3);
SPT = South Pole Telescope (SPT) clusters (section 3.1;
see Bleem+, 2015, J/ApJS/216/27);
RNA = Red Near Anything (section 3.4).
Note (2): The names match those which label the system images in the panels
in Fig. 6 to Fig. 16.
Note (3): Reference as follows:
a = Bleem et al. (2015, J/ApJS/216/27),
b = Nord et al. (2017, in preparation),
c = Menanteau et al. (2012ApJ...748....7M 2012ApJ...748....7M),
d = Zitrin et al. (2013ApJ...770L..15Z 2013ApJ...770L..15Z),
e = Stark et al. (2013MNRAS.436.1040S 2013MNRAS.436.1040S),
f = Moustakas & Brownstein (2017, in preparation),
g = Menanteau et al. (2010ApJ...723.1523M 2010ApJ...723.1523M),
h = Nord et al. (2016ApJ...827...51N 2016ApJ...827...51N),
i = Lin et al. (2017ApJ...838L..15L 2017ApJ...838L..15L),
j = Staniszewski et al. (2009ApJ...701...32S 2009ApJ...701...32S),
k = Mehlert et al. (2001A&A...379...96M 2001A&A...379...96M),
l = Song et al. (2012, J/ApJ/761/22),
m = Collett et al. (2017ApJ...843..148C 2017ApJ...843..148C),
n = Bayliss et al. (2011, J/ApJS/193/8),
o = Hennawi et al. (2008AJ....135..664H 2008AJ....135..664H),
p = More et al. (2012MNRAS.455.1191M 2012MNRAS.455.1191M),
q = Sonnenfeld et al. (2017arXiv170401585S 2017arXiv170401585S),
r = Gomez et al. (2012AJ....144...79G 2012AJ....144...79G),
s = Greve et al. (2012ApJ...756..101G 2012ApJ...756..101G),
t = Aravena et al. (2013MNRAS.433..498A 2013MNRAS.433..498A),
u = Menanteau et al. (2010ApJS..191..349M 2010ApJS..191..349M),
v = Buckley-Geer et al. (2011, J/ApJ/742/48).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [DES]
4- 13 A10 --- DES System identifier (JHHMM+DDMM) (1)
15 A1 --- --- [(]
16 A1 --- m_DES Lens (if letter) or source (if number) within
the respective cutouts
17 A1 --- --- [)]
19- 28 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
30- 39 F10.6 deg DEdeg Declination in decimal degrees (J2000)
41- 45 F5.2 mag gmag [16.5/27.1]? DESDM database g band magnitude
47- 50 F4.2 mag e_gmag [0/1]? Uncertainty in gmag
52- 56 F5.2 mag rmag [15.6/24.4]? DESDM database r band magnitude
58- 61 F4.2 mag e_rmag [0/0.4]? Uncertainty in rmag
63- 67 F5.2 mag imag [15.2/24.2]? DESDM database i band magnitude
69- 72 F4.2 mag e_imag [0/0.4]? Uncertainty in imag
74- 78 F5.2 mag zmag [14.9/24]? DESDM database z band magnitude
80- 83 F4.2 mag e_zmag [0/0.9]? Uncertainty in zmag
85- 89 F5.2 mag Ymag [14.9/27]? DESDM database Y band magnitude (2)
91- 94 F4.2 mag e_Ymag [0/1]? Uncertainty in Ymag
96- 99 F4.2 --- zphot [0.06/2]? Photometric redshift
101-104 F4.2 --- e_zphot [0.02/0.3]? Uncertainty in zphot (3)
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Note (1): System Name refers to the arc or lensed source image as shown in
Table 2 and in Figs. 6 to 16.
Note (2): Y-band photometry is provided where available: supernova fields were
only observed in Y-band for those fields that overlap with the
wide-field survey.
Note (3): The redshift uncertainties have been multiplied by 1.5 times the
original estimate, according to the results of
Sanchez+ (2014MNRAS.445.1482S 2014MNRAS.445.1482S) for estimating uncertainties
calculated using DES photometric redshift measurement codes.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 03-Oct-2017