Asteroseismology and oblique pulsator model of β Cephei

We discuss the oscillation features of beta Cephei, which is a magnetic star in which the magnetic axis seems to be oblique to the rotation axis. We interpret the observed equidistant 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, evolutionary stage, rotational frequency, magnetic field strength, and geometrical configuration of beta Cep.