The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model

Details The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model

Jan 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000aj....119..315d&link_type=abstract

The Astronomical Journal, Volume 119, Issue 1, pp. 315-322.

Astronomy and Astrophysics

Astronomy

9

Stars: Circumstellar Matter, Planetary Nebulae: Individual (Mycn 18), Stars: Agb And Post-Agb, Stars: Mass Loss

Scientific paper

We have observed MyCn18, a young planetary nebula, with Hubble Space Telescope/Wide Field Planetary Camera 2 and have presented the observational results in an earlier paper. Here we present a detailed spatio-kinematic model of Hα emission from the nebula. We model the hourglass-shaped nebular lobes as thin-walled structures in the shape of modified paraboloids. Variations in the Hα surface brightness with radius imply abrupt changes in the exponent of the power-law gas density in the hourglass walls. These density variations might reflect temporal variations in the mass-loss rate of the progenitor asympotic giant branch (AGB) star. Alternatively, they may be a result of the complex interaction between the fast and slow winds. From the Hα surface brightness variations we infer that the nebula is density-bounded everywhere, except in the vicinity of the dense waist. We derive a total mass of 0.013 Msolar for the walls of the ionized nebula and an upper limit of 0.006 Msolar for the mass in the interior. This appears to be a small fraction of the total mass ejected in the AGB phase. The nebular kinematics are well modeled with a radial velocity field where velocity increases with latitude. The density and velocity structures derived from our model are consistent with general predictions of the interacting winds hypothesis for planetary nebula formation.

Affiliated with

Also associated with

No associations

Rating

The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Etched Hourglass Nebula MYCN 18. II. A Spatio-kinematic Model will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1253071