- ... parallaxes
- Based in parts on observations
made with the NASA/ESA Hubble Space Telescope, obtained at the Space
Science Institute, which is operated by the Association of the Universities
for Research in Astronomy, Inc., under NASA contract NAS 5-26555. The data
are retrieved from the ESO/ST-ECF Science Archive Facility.
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- ...
- Appendix A is only available in electronic form at http://www.edpsciences.org
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- ... therein)
- Note that Mellema uses the ratio
while we have instead replaced
,
the post-shock velocity
(stellar frame), by the spectroscopic quantity
which is not
equal to
because of the radial velocity variation within the
rim. We found for the sequence shown in Fig. 3 that always
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- ... time
- Also called ballistic expansion.
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- ...

- With a distance of 1.4 kpc to IC 2448 the central star has
only a luminosity well below 103
,
much too low for a
post-AGB star.
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- ...
3639(Obj)
- The stellar models used in our hydrodynamical modelling are powered by
hydrogen-burning and have normal, hydrogen-rich surface
compositions.
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- ... predict
- Remember that the expansion of the shell's outer edge is thermally driven, i.e.
due to the heating by the ionizing photon flux from the star, and is not
influenced by the powerful Wolf-Rayet wind.
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