Complex distribution and velocity field of molecular gas in NGC 1316 as revealed by the Morita Array of ALMA

Abstract We present the results of 12CO(J = 1–0) mosaicing observations of the cD galaxy NGC 1316 at kiloparsec resolution performed with the Morita Array of the Atacama Large Millimeter/submillimeter Array (ALMA). We reveal the detailed distribution of the molecular gas in the central region for the first time: a shell structure in the northwest, a barely resolved blob in the southeast of the center, and some clumps between them. The total molecular gas mass obtained with a standard Milky Way CO-to-H2 conversion factor is $(5.62 \pm 0.53) \times 10^{8}\, M_{\odot }$, which is consistent with previous studies. The disturbed velocity field of the molecular gas suggests that the molecular gas was injected very recently (