PHL 932 - Another non-post-AGB central star of planetary nebula

Mendez, R. H.; Kudritzki, R. P.; Groth, H. G.; Husfeld, D.; Herrero, A.
Referencia bibliográfica

Astronomy and Astrophysics (ISSN 0004-6361), vol. 197, no. 1-2, May 1988, p. L25-L28. Research supported by the Max-Planck-Institut für Astrophysik.

Fecha de publicación:
5
1988
Número de autores
5
Número de autores del IAC
1
Número de citas
64
Número de citas referidas
54
Descripción
The very high surface gravity and low temperature of PHL 932, a hot subluminous star surrounded by a planetary nebula, imply that it cannot be a post-AGB star. It thus becomes the second object of this kind discovered spectroscopically. The spectroscopic evidence is presented, and some properties of the nebulae around these two stars are inferred. It is suggested that these two nonpostasymptotic giant branch planetary nebulae can only be understood as a consequence of a common-envelope phase in the evolution of close binary systems on the first red giant branch. This does not mean that both objects have to be close binary systems, because the common-envelope episode may have ended in both cases with the coalescence of the two components into a single star. In a final section, some comments are made about possible ways of searching for additional nonpostasymptotic giant branch central stars of planetary nebulae.