HST STIS UV Spectroscopic Observations of the Protoplanetary Nebula Hen3-1475 [SSA]

http://arxiv.org/abs/1810.00634


We present UV spectra of the protoplanetary nebula (pPN) Hen3-1475 obtained with the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). Our deep, low-dispersion spectroscopy enables monochromatic imaging of Hen3-1475 in UV nebular emission lines, the first of such attempt ever made for a pPN. The high spatial resolution of STIS imaging allows an unprecedentedly sharp view of the S-shaped jet, especially the inner NW1 knot, which is resolved into four components in the MgII 2800 line emission. Through critical comparison with HST optical narrowband images, we found a negative radial velocity gradient in NW1, from -1550 km/s on its innermost component to about -300 km/s on the outermost. Despite their high radial velocities, these components of NW1 mostly show no obvious (or very small) proper motions, indicating that they might be quasi-stationary shocks near the tip of the conical flow along the collimated jet of Hen3-1475.

Read this paper on arXiv…

X. Fang, A. Castro, J. Toala, et. al.
Tue, 2 Oct 18
65/84

Comments: Accepted for publication in The Astrophysical Journal Letters (ApJL); 6 pages, including 4 figures and 1 table