Abstract
Some planetary nebulae (PNe) show microstructures of low ionization located in their outer regions, i.e. external to the bright rim defined by the fast vs. slow wind interaction region. Morphological and kinematic analysis of some of these PNe show low ionization knots which clearly share the expansion of the outer shell of the host nebulae (e.g. IC 2553). Sometimes, these knots possess an accentuated degree of symmetry. Given that in situ instabilities are not thought to form symmetrical features, we explore the idea that these symmetric pairs of knots are fossil condensations of the AGB wind being modified by interaction with the expanding ionization front. This very appealing possibility would imply that the mass loss of the pre-PN stages has episodes of highly collimated and symmetric ejections. In other PNe knots of low ionization in the outer shells are not symmetric (e.g. NGC 5882) and could be formed by either simple in situ instabilities and/or fossil condensations.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Balick, B., Hajian, A. R., Terzian, Y., Perinotto, M., and Patriarchi, P. 1998, AJ, 116, 360
Corradi, R. L. M., Gonçalves, D. R. Villaver, E., Mampaso, A., and Perinotto, M. 2000, ApJ, 542, in press (astro-ph/0003238)
Corradi, R. L. M., Manso, R., Mampaso, A., and Schwarz, H. E. 1996, AandA, 313, 913
Garcia-Segura, G., and Franco, J. 1996, ApJ, 469, 171
Gonçalves, D. R., Corradi, R. L. M., and Mampaso, A. 2000, ApJ, 547, in press (astro-ph/0010282)
Livio, M., and Pringle, J. E. 1997, ApJ, 486, 835
Mellema, G., Raga, A. C., Canto, J., Lundqvist, P., Balick, B., Steffen, W., and Noriega-Crespo, A. 1998, AandA, 331, 335
Soker, N., and Harpaz, A. 1999, MNRAS, 310, 1158
Soker, N., and Reveg, O. 1998, AJ, 116, 2462
Solf, J., and Ulrich, H. 1985, AandA, 148, 274
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2001 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Gonçalves, D.R., Corradi, R.L.M., Villaver, E., Mampaso, A., Perinotto, M. (2001). Are Microstructures in the Outer Shells of PNe Fossil Condensations of the AGB Wind?. In: Szczerba, R., Górny, S.K. (eds) Post-AGB Objects as a Phase of Stellar Evolution. Astrophysics and Space Science Library, vol 265. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-9688-6_23
Download citation
DOI: https://doi.org/10.1007/978-94-015-9688-6_23
Publisher Name: Springer, Dordrecht
Print ISBN: 978-90-481-5758-7
Online ISBN: 978-94-015-9688-6
eBook Packages: Springer Book Archive