Non-local thermodynamic equilibrium line profiles, rotation, and magnetic fields in seven DA white dwarfs

Bibcode
1988ApJ...332..910K
DOI
10.1086/166700
Koester, D.; Herrero, A.
Referencia bibliográfica

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 332, Sept. 15, 1988, p. 910-916.

Fecha de publicación:
9
1988
Revista
Astrophysical Journal
Número de autores
2
Número de autores del IAC
1
Número de citas
33
Número de citas referidas
28
Descripción
Non-LTE calculations of H-alpha line profiles are presented and applied to derive rotational velocities from high-resolution spectra of DA white dwarfs. This paper extends recent work by Pilachowski and Milkey (1984, 1987) to southern hemisphere objects and confirms their findings that all white dwarfs seem to be slow rotators. Of the seven objects in this study only one has v sin 1 = 30 + or - 20 km/s, only marginally different from 0. The remaining objects are all fitted by v sin 1 = 0, and upper limits of 20-40 km/s were obtained. Upper limits on magnetic fields of 25,000 G were determined for all objects from the absence of Zeeman splitting.
Tipo
Con árbitro
Campos magnéticos estelares
Rotación estelar
Estrellas enanas blancas

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