We study the dynamical status of the galaxy system ZwCl 2341.1+0000, a
filamentary multi-Mpc galaxy structure associated with a complex diffuse radio
emission. Our analysis is mainly based on new spectroscopic data for 128
galaxies acquired at the TNG telescope. We also use optical data available in
the SDSS and X-ray data from the Chandra archive. We select 101 cluster member
galaxies and compute the cluster redshift ~0.2693 and the global LOS
velocity dispersion ~1000 km/s. Our optical analysis agrees with the presence
of at least three, likely four or more, optical subclusters causing the SSE-NNW
elongation of the galaxy distribution and a significant velocity gradient in
the S-N direction. In particular, we detect an important low-velocity subclump
in the southern region, roughly coincident with the brightest peak of the
diffuse radio emission but with a clear offset between the optical and radio
peaks. We also detect one (or two) optical subcluster(s) at north, in
correspondence with the second brightest radio emission, and another one in the
central cluster region, where a third diffuse radio source has been recently
detected. A more refined analysis involving the study of the 2D galaxy
distribution suggests an even more complex structure. As for the X-ray
analysis, we confirm the SSE-NNW elongation of the intracluster medium and
detect four significant peaks. The X-ray emission is strongly asymmetric and
offsetted with respect to the galaxy distribution, thus suggesting a merger
caught in the phase of post-core-core passage. Our findings support two
possible hypotheses for the nature of the diffuse radio emission of ZwCl
2341.1+0000: a 2 relics+halo scenario or diffuse emission associated with the
infall and merging of several galaxy groups during the first phase of the
cluster formation.Comment: 14 pages, 14 figures, 4 tables; MNRAS in pres
