Issue |
A&A
Volume 400, Number 3, March IV 2003
|
|
---|---|---|
Page(s) | 957 - 969 | |
Section | Interstellar and circumstellar matter | |
DOI | https://doi.org/10.1051/0004-6361:20030079 | |
Published online | 07 March 2003 |
Kinematics, turbulence and evolution of planetary nebulae *,**
1
Centrum Astronomii UMK, ul. Gagarina 11, 87-100 Torun, Poland
2
Observatoire astronomique de Strasbourg, 11 rue de l'Université, 67000 Strasbourg, France e-mail: acker@astro.u-strasbg.fr
3
Astrophysics Group, Physics Department, UMIST, PO Box 88, Manchester M60 1QD, UK e-mail: a.zijlstra@umist.ac.uk
Corresponding author: K. Gesicki, Krzysztof.Gesicki@astri.uni.torun.pl
Received:
23
October
2002
Accepted:
6
January
2003
This paper discusses the location of a sample of planetary nebulae on
the HR diagram. We determine the internal velocity fields of 14 planetary nebulae from high-resolution echelle spectroscopy, with the
help of photoionization models. The mass averaged velocity is shown to
be a robust, simple parameter describing the outflow. The
expansion velocity and radius are used to define the dynamical age;
together with the stellar temperature, this gives a measurement of the
luminosity and core mass of the central star. The same technique is
applied to other planetary nebulae with previously measured
expansion velocities, giving a total sample of 73 objects. The objects
cluster closely around the Schönberner track of 0.61 , with
a very narrow distribution of core masses. The masses are higher than
found for local white dwarfs. The luminosities determined in this way
tend to be higher by a factor of a few than those derived from the
nebular luminosities. The discrepancy is highest for the hottest (most
evolved) stars. We suggest photon leakage as the likely cause. The
innermost regions of the non-[WC] nebulae tend to show strong
acceleration. Together with the acceleration at the ionization front,
the velocity field becomes “U”-shaped. The presence of strong
turbulent motions in [WC] nebulae is confirmed. Except for this, we
find that the [WC] stars evolve on the same tracks as non-[WC] stars.
Key words: planetary nebulae: general / stars: evolution / stars: Hertzsprung-Russell (HR) and C-M diagrams
© ESO, 2003
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