Populations of Magnetized Filaments in the Intracluster Medium and the Galactic Center

Abstract

Magnetized radio filaments are found in abundance in the inner few hundred parsecs of our galaxy. Progress in understanding this population of filaments has been slow over the last few decades, in part due to a lack of detection elsewhere in the galaxy or in external galaxies. Recent highly sensitive radio continuum observations of radio galaxies in galaxy clusters have revealed remarkable isolated filamentary structures in the intracluster medium (ICM) that are linked to radio jets, tails, and lobes. The origin of this class of filaments is not understood either. Here, we argue that the underlying physical mechanisms responsible for the creation of the two populations are the same because of their similarities in morphology, spacing between the filaments, aspect ratio, and magnetic energy densities to the thermal pressure of the medium and that both populations have undergone synchrotron aging. These similarities provide an opportunity to investigate the physical processes in the interstellar medium (ISM) and ICM for the first time. We consider that the origin of the filaments in both the Galactic center and ICM is a result of the interaction of a large-scale wind with clouds, or the filaments arise through the stretching and collection of field lines by turbulence in a weakly magnetized medium. We examine these ideas in four radio galaxy filaments associated with four radio galaxies—IC 40B, IC 4496, J1333–3141, ESO 137–006—and argue that much can be understood in the future by comparing these two populations of filaments.