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.)