DETECTION OF AN H-I-DISK IN HYDRA-A

We present new observations of the H I absorption system seen toward t he core of the radio galaxy Hydra A, which is the central galaxy in a cooling flow cluster Abell 780. Our improved spatial (similar to 2 '') and velocity (similar to 1.4 km s(-1)) resolutions indicate that the absorption arises very close to the nucleus, probably in a gas disk lo cated in the central regions of the galaxy. There is no indication tha t any of the absorption arises in the cooling flow. The H I absorption is seen only toward the core and is within similar to 100 km s(-1) of the systemic velocity. The absorption covers a velocity range similar to 100 km s(-1). It can be decomposed into six Gaussian components wi th widths similar to 10-20 km s(-1) and optical depths similar to 0.1- 0.5. No narrow line features (similar to 1 km s(-1)) were detected in Hydra A to a 3 sigma optical depth limit of 0.06.