The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB

Details The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB

2002-02-01

arxiv.org/abs/astro-ph/0202050v1

Astronomy and Astrophysics

Astrophysics

43 pages, 15 figures. Accepted for publication in the Astrophysical Journal

Scientific paper

10.1086/340022

We have investigated the dynamical interaction of low- and-intermediate mass stars (from 1 to 5 Msun) with their interstellar medium (ISM). In this first paper, we examine the structures generated by the stellar winds during the Asymptotic Giant Branch (AGB) phase, using a numerical code and the wind history predicted by stellar evolution. The influence of the external ISM is also taken into account. We find that the wind variations associated with the thermal pulses lead to the formation of transient shells with an average lifetime of 20,000 yr, and consequently do not remain recorded in the density or velocity structure of the gas. The formation of shells that survive at the end of the AGB occurs via two main processes: shocks between the shells formed by two consecutive enhancements of the mass-loss or via continuous accumulation of the material ejected by the star in the interaction region with the ISM. Our models show that the mass of the circumstellar envelope increases appreciably due to the ISM material swept up by the wind (up to 70 % for the 1 Msun stellar model). We also point out the importance of the ISM on the deceleration and compression of the external shells. According to our simulations, large regions (up to 2.5 pc) of neutral gas surrounding the molecular envelopes of AGB stars are expected. These large regions of gas are formed from the mass-loss experienced by the star during the AGB evolution.

Affiliated with

Also associated with

No associations

Rating

The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB 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 dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-232379