Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 355, 1080-1086 (2000)

Table of Contents
Available formats: HTML | PDF | (gzipped) PostScript

Magnetic field geometries of two slowly rotating Ap/Bp stars: HD 12288 and HD 14437

G.A. Wade 1, D. Kudryavtsev 2, I.I. Romanyuk 2, J.D. Landstreet 3 and G. Mathys 4

1 Astronomy Department, The University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6
2 Special Astrophysical Observatory, Russian Academy of Sciences, 357 147 Niznij Arkhyz, Russia
3 Physics & Astronomy Department, University of Western Ontario, London, Ontario, Canada N6A 3K7
4 European Southern Observatory, Casilla 19001, Santiago 19, Chile

Received 20 December 1999 / Accepted 20 January 2000


In this paper we report magnetic field models and basic physical parameters for the slowly rotating Ap/Bp stars HD 12288 and HD 14437.

Using new and previously published mean longitudinal magnetic field, mean magnetic field modulus, and HIPPARCOS photometric measurements, we have inferred the rotational periods of both stars (HD 12288: [FORMULA]; HD 14437: [FORMULA]). From the magnetic measurements we have determined the best-fit decentred magnetic dipole configurations. For HD 12288, we find that the field geometry is consistent with a centred dipole, while for HD 14437 a large decentring parameter [FORMULA] is inferred. Both stars show one angle in the ambiguous [FORMULA] couplet which is smaller than about [FORMULA]. This is consistent with the observation of Landstreet & Mathys (2000), who point out that almost all magnetic Ap stars with periods longer than about 30 days exhibit magnetic fields aligned with their rotational axis.

Key words: polarization – stars: chemically peculiar – stars: evolution – stars: individual: HD 12288 – stars: individual: HD 14437 – stars: magnetic fields

Send offprint requests to: G.A. Wade

© European Southern Observatory (ESO) 2000

Online publication: March 21, 2000