Bibcode
Gonçalves, D. R.; Mampaso, A.; Corradi, R. L. M.; Perinotto, M.
Bibliographical reference
Asymmetrical Planetary Nebulae III: Winds, Structure and the Thunderbird, Proceedings of the conference held 28 July - 1 August 2003 at Mt. Rainer, Washington, USA. Edited by Margaret Meixner, Joel H. Kastner, Bruce Balick and Noam Soker. ASP Conference Proceedings, Vol. 313. San Francisco: Astronomical Society of the Pacific, 2004., p.198
Advertised on:
7
2004
Citations
1
Refereed citations
1
Description
We are carrying out a study of the physical parameters and excitation of
low-ionization structures (LIS) in planetary nebulae (PNe). Since the
optical morphology and kinematics of the LIS and the main components
(rims, shells and haloes) of our sample were studied previously, our
main goal now is to search for: i) the density contrasts between
jets/knots and the main nebular components; ii) their main excitation
processes; and iii) their chemical abundances. The first results of this
survey --- based on the analysis of NGC 7009, NGC 6543, NGC 6891 and K
4-47 --- are that there is no significant density contrast between LIS
and their surroundings, and that most of the LIS studied (but not all)
are mainly photoionized, rather than shock excited.