J/ApJ/833/194 Group of galaxies in gravitational lens fields (Wilson+, 2016)
A spectroscopic survey of the fields of 28 strong gravitational lenses:
the group catalog.
Wilson M.L., Zabludoff A.I., Ammons S.M., Momcheva I.G., Williams K.A.,
Keeton C.R.
<Astrophys. J., 833, 194-194 (2016)>
=2016ApJ...833..194W 2016ApJ...833..194W (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing ; Spectroscopy ; Redshifts ;
Velocity dispersion ; Clusters, galaxy
Keywords: catalogs; galaxies: groups: general; gravitational lensing: strong
Abstract:
With a large, unique spectroscopic survey in the fields of 28
galaxy-scale strong gravitational lenses, we identify groups of
galaxies in the 26 adequately sampled fields. Using a group-finding
algorithm, we find 210 groups with at least 5 member galaxies; the
median number of members is 8. Our sample spans redshifts of
0.04≤zgrp≤0.76 with a median of 0.31, including 174 groups with
0.1<zgrp<0.6. The groups have radial velocity dispersions of
60≤σgrp≤1200km/s with a median of 350km/s. We also discover
a supergroup in field B0712+472 at z=0.29 that consists of three main
groups. We recover groups similar to ∼85% of those previously reported
in these fields within our redshift range of sensitivity and find 187
new groups with at least five members. The properties of our group
catalog, specifically, (1) the distribution of σgrp, (2) the
fraction of all sample galaxies that are group members, and (3) the
fraction of groups with significant substructure, are consistent with
those for other catalogs. The distribution of group virial masses
agrees well with theoretical expectations. Of the lens galaxies, 12 of
26 (46%) (B1422+231, B1600+434, B2114+022, FBQS J0951+2635,
HE0435-1223, HST J14113+5211, MG0751+2716, MGJ1654+1346, PG 1115+080,
Q ER 0047-2808, RXJ1131-1231, and WFI J2033-4723) are members of
groups with at least five galaxies, and one more (B0712+472) belongs
to an additional, visually identified group candidate. There are
groups not associated with the lens that still are likely to affect
the lens model; in six of 25 (24%) fields (excluding the supergroup),
there is at least one massive (σgrp≥500km/s) group or group
candidate projected within 2' of the lens.
Description:
Images of each lens field were collected using the Mosaic-1 imager on
the Kitt Peak National Observatory Mayall 4m telescope and the
Mosaic-2 imager on the Cerro Tololo Inter-American Observatory Blanco
4m telescope. Williams+ (2006ApJ...646...85W 2006ApJ...646...85W) detail these data and
their reduction.
The spectroscopic follow-up is described in Momcheva+ (2015,
J/ApJS/219/29): a sample of objects from the photometry was selected
for spectroscopic follow-up using Hectospec on the MMT 6.5m telescope
and LDSS-2, LDSS-3, and IMACS on the Magellan 6.5m telescopes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 142 210 Algorithmically identified groups with ≥5 members
table2.dat 142 59 Group catalog supplement: algorithmically
identified groups with 3-4 members
table3.dat 109 4 Group catalog supplement: supergroup and
its substructures in Field b0712
table4.dat 127 23 Group catalog supplement: visually identified
candidate groups
table5.dat 48 2685 Algorithmic group members
table6.dat 48 374 Supergroup members
table7.dat 48 225 Visually identified candidate group members
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See also:
J/ApJS/219/29 : Spectrosc. redshifts in strong lens fields (Momcheva+, 2015)
J/A+A/566/A1 : Flux & volume limited groups for SDSS galaxies (Tempel+, 2014)
J/ApJ/781/2 : Redshifts of 1151 galaxies from SDSS (Ammons+, 2014)
J/ApJ/753/121 : zCOSMOS 20k sample group catalog to z≲1.2 (Knobel+, 2012)
J/MNRAS/422/25 : SDSS DR7 groups, clusters and filaments (Smith+, 2012)
J/AJ/142/170 : ALFALFA: the α.40 HI source catalog (Haynes+, 2011)
J/A+A/507/671 : Cluster RDCS J1252.9-2927 (z=1.2) spectroscopy (Tanaka+, 2009)
J/MNRAS/395/255 : Compact groups of galaxies in SDSS DR6 (McConnachie+, 2009)
J/MNRAS/392/135 : Galaxy clusters from SDSS (Lopes+, 2009)
J/ApJS/176/374 : WARPS-II Cluster catalog. VII. (Horner+, 2008)
J/ApJ/663/164 : VLT and ACS observations in RDCS J1252.9-2927 (Demarco+, 2007)
J/ApJS/167/1 : Galaxy groups and clusters from SDSS (Berlind+, 2006)
J/ApJ/645/955 : ChaMP serendipitous galaxy cluster survey (Barkhouse+, 2006)
J/ApJ/641/169 : Spectroscopy in lens fields (Momcheva+, 2006)
J/AJ/130/968 : SDSS-C4 cluster catalog (Miller+, 2005)
J/ApJ/552/427 : Galaxy groups a intermediate redshifts (Carlberg+, 2001)
J/ApJS/130/237 : LCRS loose groups of galaxies (Tucker+, 2000)
J/ApJS/125/35 : ACO clusters redshifts & velocity dispersions (Struble+ 1999)
J/ApJ/496/39 : Properties of poor groups of galaxies. I. (Zabludoff+ 1998)
J/AJ/113/483 : Groups of Galaxies (Ramella+ 1997)
J/A+A/310/8 : The ESO Nearby Abell Cluster Survey I. (Katgert+, 1996)
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field identifier
10- 11 I2 --- Group [0/31] Group number within Field
13 A1 --- f_Group [a] a=lens group
15- 16 I2 --- Nm [3/66] Number of group members
18- 23 F6.4 --- zgrp [0.02/0.8] Redshift of the group
25- 30 F6.4 --- e_zgrp [0/0.002]? Negative uncertainty on zgrp (G1)
32- 37 F6.4 --- E_zgrp [0/0.003]? Positive uncertainty on zgrp (G1)
39- 46 F8.4 deg RAdeg Right ascension (J2000)
48- 53 F6.4 deg e_RAdeg [0.001/0.09]? RAdeg negative uncertainty (G1)
55- 60 F6.4 deg E_RAdeg [0.001/0.1]? RAdeg positive uncertainty (G1)
62- 69 F8.4 deg DEdeg Declination (J2000)
71- 76 F6.4 deg e_DEdeg [0.001/0.06]? DEdeg negative uncertainty (G1)
78- 83 F6.4 deg E_DEdeg [0.001/0.06]? DEdeg positive uncertainty (G1)
85- 89 F5.2 arcmin Dist [0.1/18] Projected distance (R) between
the lens and the group centroid
91- 94 I4 km/s sigma [20/1200] Group dispersion velocity
96- 98 I3 km/s e_sigma [3/460]? Negative uncertainty on sigma (G1)
100-102 I3 km/s E_sigma [10/420]? Positive uncertainty on sigma (G1)
104-108 F5.1 10+13Msun Mvir [1/145]? Virial mass (G2)
110-116 F7.4 10+13Msun e_Mvir [0.0003/75]? Negative uncertainty on Mvir (G1)
118-121 F4.1 10+13Msun E_Mvir [0.4/63]? Positive uncertainty on Mvir (G1)
123-126 F4.2 Mpc rvir [0.03/2.9] Virial radius rvir
128-134 A7 --- Flag Flag(s) on Group (G3)
136-142 A7 --- Match Groups in the literature that have a
redshift within 3σz of a group in
our catalog (1)
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Note (1): The reference abbreviations are as follows:
AFALS07 = Auger et al. (2007AJ....134..668A 2007AJ....134..668A);
AFW08 = Auger et al. (2008ApJ...673..778A 2008ApJ...673..778A),
CCN07 = Carrasco et al. (2007, J/ApJ/664/777),
DG92 = Dressler & Gunn (1992, J/ApJS/78/1),
KSG = Katgert+ (1996, J/A+A/310/8), Struble & Rood (1999ApJS..125...35S 1999ApJS..125...35S),
and Gastaldello+ (2003A&A...411...21G 2003A&A...411...21G),
LCKJ09 = Lopes et al. (2009, J/MNRAS/392/135),
MB = Mason+ (2000, J/MNRAS/311/456) and Barkhouse+ (2006, J/ApJ/645/955),
MPES09 = McConnachie et al. (2009, J/MNRAS/395/255),
MNR05 = Miller et al. (2005, J/AJ/130/968),
TOH00 = Tucker et al. (2000, J/ApJS/130/237),
WMKZL06 = Williams et al. (2006ApJ...646...85W 2006ApJ...646...85W),
WH = Williams+ (2006ApJ...646...85W 2006ApJ...646...85W) and Horner+ (2008, J/ApJS/176/374)
BHS = Berlind+ (2006, J/ApJS/167/1), Haynes+ (2011, J/AJ/142/170), and
Smith et al. (2012, J/MNRAS/422/25)
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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 I1 --- Group [0/3] Group number within Field
3- 5 I3 --- Nm [39/230] Number of group members
7- 12 F6.4 --- zgrp [0.28/0.3] Redshift of the group
14- 19 F6.4 --- e_zgrp [0.0002/0.0003]? Negative uncertainty on zgrp
21- 26 F6.4 --- E_zgrp [0.0002/0.0004]? Positive uncertainty on zgrp
28- 35 F8.4 deg RAdeg Right ascension (J2000)
37- 42 F6.4 deg e_RAdeg [0.009/0.02]? Negative uncertainty on RAdeg
44- 49 F6.4 deg E_RAdeg [0.01/0.02]? Positive uncertainty on RAdeg
51- 57 F7.4 deg DEdeg Declination (J2000)
59- 64 F6.4 deg e_DEdeg [0.007/0.009]? Negative uncertainty on DEdeg
66- 71 F6.4 deg E_DEdeg [0.007/0.009]? Positive uncertainty on DEdeg
73- 77 F5.2 arcmin Dist [0.9/12] Projected distance (R) between
the lens and the group centroid
79- 82 I4 km/s sigma [330/1170] Group dispersion velocity
84- 85 I2 km/s e_sigma [30/60]? Negative uncertainty on sigma
87- 88 I2 km/s E_sigma [30/60]? Positive uncertainty on sigma
90- 94 F5.1 10+13Msun Mvir [3/120]? Virial mass when ≥1013M☉
96- 99 F4.1 10+13Msun e_Mvir [0.9/14]? Negative uncertainty on Mvir
101-104 F4.1 10+13Msun E_Mvir [1/12]? Positive uncertainty on Mvir
106-109 F4.2 Mpc rvir [0.7/2.5] Virial radius rvir
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field identifier
10- 12 A3 --- Group Group number within Field (not continued
from tables 1 and 2)
14 A1 --- f_Group [a] a=lens group
16- 17 I2 --- Nm [3/28] Number of group members
19- 24 F6.4 --- zgrp [0.1/0.7] Redshift of the group
26- 31 F6.4 --- e_zgrp [0/0.002]? Negative uncertainty on zgrp (G1)
33- 38 F6.4 --- E_zgrp [0/0.002]? Positive uncertainty on zgrp (G1)
40- 47 F8.4 deg RAdeg Right ascension (J2000)
49- 54 F6.4 deg e_RAdeg [0.006/0.05]? RAdeg negative uncertainty (G1)
56- 61 F6.4 deg E_RAdeg [0.006/0.06]? RAdeg positive uncertainty (G1)
63- 70 F8.4 deg DEdeg Declination (J2000)
72- 77 F6.4 deg e_DEdeg [0.004/0.06]? DEdeg Negative uncertainty (G1)
79- 84 F6.4 deg E_DEdeg [0.004/0.06]? DEdeg positive uncertainty (G1)
86- 90 F5.2 arcmin Dist [1/11] Projected distance (R) between
the lens and the group centroid
92- 95 I4 km/s sigma [220/1010] Group dispersion velocity
97- 99 I3 km/s e_sigma [90/570]? Negative uncertainty on sigma (G1)
101-103 I3 km/s E_sigma [50/710]? Positive uncertainty on sigma (G1)
105-108 F4.1 10+13Msun Mvir [1/81]? Virial mass (G2)
110-113 F4.1 10+13Msun e_Mvir [0.1/39]? Negative uncertainty on Mvir (G1)
115-118 F4.1 10+13Msun E_Mvir [0.8/51]? Positive uncertainty on Mvir (G1)
120-123 F4.2 Mpc rvir [0.4/2.3] Virial radius rvir
125-127 A3 --- Flag Flag(s) on Group (G3)
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Byte-by-byte Description of file: table[567].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field identifier
10- 12 A3 --- Group Group identifier (0-31) or
supergroup identifier (0-3) or candidate
group identifier (i-iv)
14- 20 F7.5 --- z [0.02/0.8] Galaxy redshift
22- 28 F7.5 --- e_z [/0.002] Uncertainty in z
30- 38 F9.5 deg RAdeg Right Ascension in decimal degrees (J2000)
40- 48 F9.5 deg DEdeg Declination in decimal degrees (J2000)
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Global notes:
Note (G1): Uncertainties are not calculated for Nm<4.
Note (G2): Masses are reported when ≥1013M☉.
Note (G3): Flag as follows:
1 = zgrp<0.1 (groups at lower redshift are most likely not sampled out to
rvir because of the spectroscopic field size);
2 = rvir intersects the edge of the well-sampled region of the field because
the group is large and/or at low z;
3 = rvir extends beyond the well-sampled region of the field because the
group centroid or several of its members are near the edge of the field;
4 = group membership was adjusted manually to remedy overlapping membership.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 28-Apr-2017