NH-NHI correlation in gigahertz-peaked-spectrum galaxies†

With the Westerbork Synthesis Radio Telescope, we performed H I observations of a sample of known X-ray emitting Gigahertz-peaked-spectrum galaxies with compact-symmetric-object morphology (GPS/CSOs) that lacked an H I absorption detection. We combined radio and X-ray data of the full sample of X-ray emitting GPS/CSOs and found a significant, positive correlation between the column densities of the total and neutral hydrogen (NH and NHI, respectively). Using a Bayesian approach, we simultaneously quantified the parameters of the NH-NHI relation and the intrinsic spread of the data set. For a specific subset of our sample, we found NH ∝ NHI b, with b=0.93+0.49-0.33, and σ_int(NH)= 1.27+1.30-0.40. The NH-NHI correlation suggests a connection between the physical properties of the radio and X-ray absorbing gas. Data from the Westerbork Synthesis Radio Telescope