The dynamical processes of the interaction of slow wind
beyond Red Giant phase with fast wind of central star of nebula are evaluated.
The mechanism of interaction stellar wind model (ISW) is found to be
responsible for producing a relatively dense shell of gas which increases in mass
and radius at a constant rate. Both slow wind and superwind are assumed to be
time independent and radial density is calculated at initial time to~ 60 yrs with the
fast wind velocity (v≈1000
km/s). The results showed that, at the outer rim of super wind region, a
small density hump appears due to the relative velocity between slow winds and
central star winds, in a good agreement with the previous models. The dynamical
requirements of the observed expansion of planetary nebulae can be satisfied by
the mechanism of interacting stellar wind model with reasonable mass loss rate
from central star.
B. A. Sargent, et al., “The Mass Loss Return from Evolved Stars to Large Magellanc Cloud II. Dust Properties for Oxygen-Rich Asymptotic Giant Branch Stars,” Astrophysical Journal, Vol. 716, No. 1, 2010, pp. 878-881.
H. Umeda, T. Yoshida and K. Takashi, “Massive Star Evolution and Nucleosynthesis: Lower End of Fe-CoreCollapse Supernova Progenitors and Remnant Nutron Star Mass Distribution,” Progress of Theoretical and Experimental Physics, 2012, Article ID: 01A302.