Previous abstract Next abstract
Session 41 - Jets and Outflows from YSOs.
Display session, Tuesday, June 11
We present new HST images of the HH 47 and HH 111 jets taken in H-alpha and [S II]. These are the deepest (typically 3000s exposure times) space-based images of stellar jets to date, and clearly show a number of remarkable structures that are invisible from the ground.
In both jets, the Halpha emission concentrates into a series of sharp arcs that surround the collimated flow outlined by the [S II]. These Halpha features are particularly useful because they mark the location of the shocks in the flow as neutral hydrogen becomes collisionally excited at the front. The principal bow shocks in the flows are well-resolved, and in most cases we can see both the bow shock and the Mach disk in the flow. The jets are not perfectly straight, and drive shocks into the surround medium as they move away from the exciting source.
In both HH 111 and HH 47 it appears that velocity variability, combined with changes in the ejection direction of the jet produce the observed shock fronts.
Program listing for Tuesday