The high-velocity outflow in the proto-planetary nebula Hen 3-1475

Astrophysics, abstract
astro-ph/0303111

From: Angels Riera <angels.riera@upc.es>

Date: Wed, 5 Mar 2003 13:57:15 GMT   (215kb)

Authors:
A. Riera,
P. Garcia-Lario,
A. Manchado,
M. Bobrowsky,
R. Estalella

Comments: 19 pages, 8 figures, accepted for publication in A&A

The proto-planetary nebula Hen 3-1475 shows a remarkable highly collimated
optical jet with an S-shaped string of three pairs of knots and extremely high
velocities. We present here a detailed analysis of the overall morphology,
kinematic structure and the excitation conditions of these knots based on deep
ground-based high dispersion spectroscopy complemented with high spatial
resolution spectroscopy obtained with STIS onboard HST, and WFPC2 [N II]
images. The spectra obtained show double-peaked, extremely wide emission line
profiles, and a decrease of the radial velocities with distance to the source
in a step-like fashion. We find that the emission line ratios observed in the
intermediate knots are consistent with a spectrum arising from the
recombination region of a shock wave with shock velocities ranging from 100 to
150 km/s. We propose that the ejection velocity is varying as a function of
time with a quasi-periodic variability (with timescale of the order of 100
years) and the direction of ejection is also varying with a precession period
of the order of 1500 years.

References and citations for this submission:

SLAC-SPIRES HEP (refers to ,
cited by, arXiv reformatted)