2005A&A...440..453D

We present a weak lensing analysis of the double cluster system Abell 222 and Abell 223. The lensing reconstruction shows evidence for a possible dark matter filament connecting both clusters. The case for a filamentary connection between A 222/223 is supported by an analysis of the galaxy density and X-ray emission between the clusters. Using the results of N-body simulations, we try to develop a criterion that separates this system into cluster and filament regions. The aim is to find a technique that allows the quantification of the significance of (weak lensing) filament candidates in close pairs of clusters. While this mostly fails, the aperture quadrupole statistics (Schneider & Bartelmann, 1997MNRAS.286..696S) shows some promise in this area. The cluster masses determined from weak lensing in this system are considerably lower than those previously determined from spectroscopic and X-ray observations (Dietrich et al., 2002A&A...394..395D; Proust et al., 2000A&A...355..443P; David et al., 1999ApJ...519..533D). Additionally, we report the serendipitous weak lensing detection of a previously unknown cluster in the field of this double cluster system.