A model for the formation of high-density clumps in proto-planetary Nebulae

Patrick A. Young, J. L. Highberger, W David Arnett, Lucy M Ziurys

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

The detection of NaCl at large radii in the Egg Nebula, CRL 2688, requires densities of 107-108 cm-3 in a thick shell of r ∼ a few × 1017 cm. To explain these results, a mechanism is needed for producing high densities at a considerable distance from the central star. In two-dimensional simulations of the interaction of the fast wind with an ambient medium, the material becomes thermally unstable. The resulting clumps can achieve the requisite conditions for NaCl excitation. We present two-dimensional models with simple physics as proof-of-principle calculations to show that the clumping behavior is robust. Clumping is a natural outcome of cooling in the colliding wind model and comparable to that inferred from observations.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume597
Issue number1 II
DOIs
StatePublished - Nov 1 2003

Fingerprint

planetary nebulae
clumps
eggs
nebulae
two dimensional models
physics
shell
egg
cooling
stars
radii
excitation
simulation
interactions
detection
calculation
material

Keywords

  • Astrochemistry
  • Hydrodynamics
  • Stars: AGB and post-AGB
  • Stars: winds, outflows

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

A model for the formation of high-density clumps in proto-planetary Nebulae. / Young, Patrick A.; Highberger, J. L.; Arnett, W David; Ziurys, Lucy M.

In: Astrophysical Journal, Vol. 597, No. 1 II, 01.11.2003.

Research output: Contribution to journalArticle

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