In this review, we identify mass loss on the asymptotic giant branch as the most important physical process that leads to the formation of planetary nebulae. The dynamics of planetary nebulae is discussed in terms of the Interacting Stellar Winds model of Kwok , Purton and FitzGerald. We also ...
Soker, N.; Kashi, A. Formation of Bipolar Planetary Nebulae by Intermediate-luminosity Optical Transients. ApJ 2012, 746, 100Soker, N. & Kashi, A. 2011, eprint: arXiv:1108.2257Kashi, A.; Soker, N. Type II intermediate-luminosity optical transients (ILOTs). Mon. Not. R. Astron. Soc....
It is generally believed that red giant mass loss plays some role in the formation of planetary nebulae (PNe), but the connection is not clearly understood. To investigate this issue we have undertaken an extensive search for molecular gas in PNe, which is likely to be remnant material of th...
Recent observations have revealed the presence of a variety of small-scale ``micro-structures'' in Planetary Nebulae images. I discuss numerical hydrodynamics models of planetaries and outline the formation and growth of instabilities that may be seen in these models. It is possible that these may...
The formation of the sun and solar nebulae is addressed, and the coagulation of grains and the formation of small planetesimals are covered, along with the gravitational accumulation of planetesimals into planetary embryos and final stages of accumulation - embryos of planets. It is pointed out ...
“solar systems” suggest that the process for this second stage recapitulates events during the first stage. Specifically, within the rings of nebulae surrounding the Sun, pancaking is followed by densification, spinup, and roundup, as well as motion of the outer local cloud outwards (Fig. 4.5...
planetary nebulae: generalstars: AGB and post-AGBGalaxy: bulgeAims: We study the star-formation history of the Galactic bulge, as derived from the age distribution of the central stars of planetary nebulae that belong to this stellar population. Methods: The high resolution imaging and ...
Finally, the overall K-band light density evolution is discussed as a tracer of the baryonic mass in stars and compared with the rate of star formation. 展开 关键词: circumstellar matter planetary nebulae, general planetary nebulae, individual (M1-92 ...
The formation of these (5, 7)-ring defects in PAHs may be well supported in asymptotic giant branch stars or planetary nebulae. These environments strongly enable the transition from the ground to the defected state. Therefore the knowledge of the IR spectra of these molecules will support ...
the angular diameters of H II regions even in some external galaxies and can thereby deduce the great distances to those remote systems. This method can be used for distances up to about 30 megaparsecs. (For additional information on H II regions,seenebula: Diffuse nebulae (H II regions).)...