ChandraObservation of the Cluster Environment of a WAT Radio Source in Abell 1446

Abstract

Wide-angle tail (WAT) radio sources are often found in the centers of galaxy clusters where intracluster medium (ICM) ram pressure may bend the lobes into their characteristic C-shape. We examine the low-redshift (z = 0.1035) cluster Abell 1446, host to the WAT radio source 1159+583. The cluster exhibits possible evidence for a small-scale cluster-subcluster merger as a cause of the WAT radio source morphology. This evidence includes the presence of temperature and pressure substructure along the line that bisects the WAT, as well as a possible wake of stripped interstellar material or a disrupted cool core to the southeast of the host galaxy. A filament to the north may represent cool, infalling gas that is contributing to the WAT bending, while spectroscopically determined redshifts of member galaxies may indicate some component of a merger occurring along the line of sight. The WAT model of high flow velocity and low lobe density is examined as another scenario for the bending of 1159+583. It has been argued that such a model would allow the ram pressure due to the galaxy's slow motion through the ICM to shape the WAT source. A temperature profile shows that the cluster is isothermal (kT = 4.0 keV) in a series of annuli reaching a radius of ~400 kpc. There is no evidence of an ongoing cooling flow. Temperature, abundance, pressure, density, and mass profiles, as well as two-dimensional maps of temperature and pressure, are presented.