ARCRAIDER II: Arc search in a sample of non-Abell clusters

Abstract

Aims: We present a search for gravitational arcs in a unique sample of X-ray luminous, medium redshift clusters of galaxies.
Methods: The sample of clusters is called ARCRAIDER, is based on the ROSAT Bright Survey (RBS) and fulfils the following criteria: (a) X-ray luminosity ≥ 0.5 × 10⁴⁵ erg/s (0.5-2 keV band), (b) redshift range 0.1 ≤ z ≤ 0.52, (c) classified as clusters in the RBS, (d) not a member of the Abell catalogue and, finally, (e) visible from the ESO sites La Silla/Paranal (declination δ ≤ 20°).
Results: In total we found more than 35 (giant) arc/arclet candidates, including a possible radial arc, one galaxy-galaxy lensing event and a possible quasar triple image in 14 of the 21 clusters of galaxies. Hence 66% of the sample members are possible lenses.

Based on observations made with ESO Telescopes at the La Silla or Paranal Observatories under programme IDs 60.A-9123(G), 65.O-0425, 67.A-0444(A), 067.A-0095(B), 67.A-0427(A), 68.A-0255(A), 69.A-0010(A), 169.A-0595(G), 072.A-0083(A), and 073.A-0050(A). Also based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA).