Hubble Space Telescope Observations of the HH47 Jet: Narrow Band Images

Heathcote, S. (CTIO), Morse, J. (CASA), Hartigan, P. (Rice), Reipurth, B. (ESO), Schwartz, R.D. (U Mo), Bally, J. (CASA), \& Stone, J. (U Md)
We present high-resolution emission line images of the remarkable Herbig-Haro jet HH 46/47 obtained with the WFPC2 aboard HST for the lines of H-alpha and [S II]. The new images resolve the sizes of the emission knots and filaments, and determine the structure and scale of the cooling zone behind the shock waves in the flow. We identify many shocks in which the Balmer emission arises predominantly from collisional excitation in the thin heating zone at the shock front. A combination of time variability in the velocity and direction of ejection can account for the sinuous structure of the jet seen in S II. The H-alpha image define several sharp filaments that resemble one-sided bow shocks which accelerate the surrounding gas. Our images also show very clearly the double shock structure of bow shock/ Mach disk in the bright know HH 47A.

(Journal of publication: Astronomical Journal 112, 1141, 1996.)