2000/06/30 by G. Soucail, J.-P. Kneib, J. P. Kneib +4 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1051/0004-6361:20000498
published as Astron.Astrophys. 367 (2001) 741-747 · 8 pages, 4 figures, uses aa.cls, accepted to Astronomy and Astrophysics with minor changes
arxiv created 2000/12/19 · openalex publication_date 2001/03/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present new optical data on the cluster AX J2019+1127 identified by the X-ray satellite ASCA at [CITE]. The data suggest the presence of a high-redshift cluster of galaxies responsible for the large separation triple quasar MG 2016+112. Our deep photometry reveals an excess of galaxy candidates, as already suspected by [CITE]. Our spectroscopic survey of 44 objects in the field shows an excess of 6 red galaxies securely identified at , with a mean redshift of . We estimate a velocity dispersion of km s-1 based on these 6 galaxies and a V-band mass-to-light ratio of . Our observations thus confirm the existence of a massive structure acting as the lens, which explains the unusual configuration of the triple quasar. Hence, there is no need to invoke the existence of a "dark cluster"to understand this lens system.