The diffuse radio filament in the merging system ZwCl 2341.1+0000

Context. In some clusters of galaxies, a diffuse non-thermal emission is present, not obviously associated with any individual galaxy. These sources have been identified as relics, mini-halos, and halos according to their properties and position with respect to the cluster center. In a few cases diffuse radio emission has been reported that cannot be identified with a cluster, but with a large scale filamentary region. Aims. We observe and analyze the diffuse radio emission present in the complex merging structure of galaxies ZwCl 2341.1+0000. Methods. We obtained VLA observations at 1.4 GHz to derive a deep radio image of the diffuse emission. Results. Low resolution VLA images detect diffuse radio emission associated with the complex merging region of size = 2.2 Mpc at most. In addition to the previously reported peripheral radio emission, classified as a double relic, diffuse emission is detected along the optical filament of galaxies. Conclusions. The giant radio source discussed here shows that magnetic fields and relativistic particles are also present in filamentary structures. Possible alternate scenarios are: a giant radio halo in-between two symmetric relics, or the merging of two clusters both hosting a central radio halo.