Asteroseismology and Oblique Pulsator Model of β Cephei
نویسندگان
چکیده
We discuss the oscillation features of β Cephei, which is a magnetic star in which the magnetic axis seems to be oblique to the rotation axis. We interpret the observed equi-distant fine structure of the frequency spectrum as a manifestation of a magnetic perturbation of an eigenmode, which would be a radial mode in the absence of the magnetic field. Besides these frequency components, we interpret another peak in the frequency spectrum as an independent quadrupole mode. By this mode identification, we deduce the mass, the evolutionary stage, the rotational frequency, the magnetic field strength, and the geometrical configuration of β Cephei. Subject headings: stars: early-type — stars: individual (β Cephei) — stars: magnetic — stars: pulsation Postdoctoral Fellow of the Fund for Scientific Research, Flanders, Belgium
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