Bibcode
DOI
Koester, D.; Herrero, A.
Bibliographical reference
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 332, Sept. 15, 1988, p. 910-916.
Advertised on:
9
1988
Journal
Citations
33
Refereed citations
28
Description
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.