A&A 384, 620-628 (2002)
DOI: 10.1051/0004-6361:20020009
Turbulent planetary nebulae around [WC]-type stars
A. Acker1, K. Gesicki2, Y. Grosdidier3 and S. Durand41 Observatoire astronomique de Strasbourg, 11 rue de l'Université, 67000 Strasbourg, France
2 Centrum Astronomii UMK, ul.Gagarina 11, 87-100 Torun, Poland
e-mail: Krzysztof.Gesicki@astri.uni.torun.pl
3 Instituto de Astrofísica de Canarias, C/. Vía Láctea s/n, 38 200 La Laguna (Tenerife), Spain
e-mail: yves@ll.iac.es
4 Instituto astronomico e geofísico da USP, Av. Miguel Stefano 4200, 04301-904, São Paulo SP, Brazil
e-mail: durand@iagusp.usp.br
(Received 19 July 2001 / Accepted 19 December 2001)
Abstract
Through a high-resolution spectroscopic survey, we analyze the velocity
field of 16 planetary nebulae with [WC]- or wels-type nuclei in
comparison with 8 nebulae having other central star types. We found
spectral evidence for finite turbulent velocities in [WC]-type planetary
nebulae superimposed on an essentially constant expansion velocity
pattern. The nebulae around O-type stars show no evidences for significant
turbulence while their expansion velocity is found to increase outwards.
Both types of nebulae show the same mean expansion velocity.
Our results support the earlier suggestions that nebulae
surrounding [WC] central stars are likely related to long-lasting
momentum-driven phase bubbles. Turbulence in the nebulae can be either
triggered, or enhanced, by stellar wind inhomogeneities that appear
ubiquitous in Wolf-Rayet nuclei.
Key words: planetary nebulae: general -- stars: Wolf-Rayet -- turbulence
Offprint request: A. Acker, acker@astro.u-strasbg.fr
SIMBAD Objects
© ESO 2002

BibSonomy
CiteUlike
Del.icio.us
Digg
Facebook
Mendeley
Twitter