The spatial distribution of excited H_2 in T Tau: a molecular outflow in a young binary system
Strong extended emission from molecular hydrogen in the v = 1 → 0 S(l) transition is mapped around T Tau. In addition, the v = 2 → 1 S(l) line is detected close to the star. The ratio of the two transitions is consistent with an excitation process in which both fluorescence by stellar ultraviolet radiation and collisions in a warm, dense medium play a role. The morphology is interpreted as emission from a molecular outflow which appears to wiggle as a result of the fact that T Tau is a binary system seen almost pole-on. It is shown that an outflow with a small opening angle can reproduce the observed extended emission. From comparison with previous studies it is argued that the molecular outflow originates from T Tau S, the infrared component. The presented model constrains the orientation and geometry of the system.
© 1994 European Southern Observatory. Provided by the NASA Astrophysics Data System. Received 3 May 1994. Accepted 19 May 1994. We are grateful to Markus Blietz, John Storey and the La Palma staff for extensive help during the observations. Nico Roos is thanked for helpful discussions on wiggling outflows. EvD and HJvL acknowledge support from the Netherlands Organization for Scientific Research (NWO), and GAB from the David and Lucille Packard and Alfred P. Sloan Foundations, as well as NASA grant NAGW-2297.
Published - 1994A+A___287L__25V.pdf