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Title: A spectroscopic survey of the fields of 28 strong gravitational lenses: The group catalog

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 ≤ z grp ≤ 0.76 with a median of 0.31, including 174 groups with 0.1 < z grp < 0.6. The groups have radial velocity dispersions of 60 ≤ σ grp ≤ 1200 km s –1 with a median of 350 km s –1. 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 σ grp, (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, 12more » 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. Furthermore, 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 (σ grp ≥ 500 km s –1) group or group candidate projected within 2' of the lens.« less
 [1] ; ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [3] ; ORCiD logo [4] ;  [5]
  1. Univ. of Arizona, Tucson, AZ (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. Space Telescope Science Institute, Baltimore, MD (United States)
  4. Texas A & M Univ., Commerce, TX (United States)
  5. Rutgers Univ., Piscataway, NJ (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1538-4357; TRN: US1701134
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 833; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; catalogs; galaxies: groups: general; gravitational lensing: strong
OSTI Identifier: