Asymmetry and inhomogeneity in proto- and young planetary nebulae

  title={Asymmetry and inhomogeneity in proto- and young planetary nebulae},
  author={Noam Soker},
  journal={Monthly Notices of the Royal Astronomical Society},
  • N. Soker
  • Published 1 December 1999
  • Physics
  • Monthly Notices of the Royal Astronomical Society
I study some effects of aspherical mass loss during the last stages of the asymptotic giant branch (AGB) on the appearance of proto-planetary nebulae (proto-PNs) and young PNs. The aspherical mass loss can be small-scale inhomogeneities, and/or axially symmetric mass-loss geometry. I first examine the role of the dust opacity in the optical band on the appearance of proto-PNs. I conclude that large optical depths will be found in proto-PNs that are post-AGB stars having high equatorial mass… Expand
Axisymmetry in protoplanetary nebulae - II. A near-infrared imaging polarimetric survey
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