Unified view and interpretation of peculiar pulsation features in roAp stars, RR Lyrae stars, Early-type stars

我讨论了快速振荡的Ap星的振荡特征，Lyrae RR星和β造父变星的Blazhko效应，并将它们解释为对恒星振荡特征函数的磁扰动的表现。roAp星的脉动幅值与地磁变化同步，幅值最大相位与地磁最大相位重合。我讨论了可利用的信息类型，并概述了如何从观测数据中推断出这些信息。我讨论了β造父变星的振荡特征，它是一颗磁轴似乎与旋转轴倾斜的磁星。我将观察到的频谱的等距精细结构解释为本征模的磁扰动的表现，在没有磁场的情况下，本征模将是径向模。除了这些频率成分，我将频谱中的另一个峰值解释为独立的四极模式。通过模态识别，推导出了β造父变星的质量、演化阶段、旋转频率、磁场强度和几何构型。假设天琴座RR星具有相当强的偶极磁场，其对称轴与恒星的旋转轴倾斜，我证明了在没有磁场的情况下，其振荡模式将是纯径向振荡，其振荡模式具有四极分量，其对称轴与磁轴重合。由于恒星自转，四极分量的纵横角会发生变化，这种明显的振幅变化被解释为天琴座RR星的布拉西克效应。结果表明，在离轴磁场的情况下，相位调制是预期的。我列出了一些基于这个模型的理论预测，这些预测将通过观察来检验这个假设。

I discuss the oscillation features of the rapidly oscillating Ap stars, the Blazhko effect of the RR Lyrae stars, and β Cephei and interpret them as being a manifestation of a magnetic perturbation to the oscillation eigenfunctions of the stars.1. The pulsation amplitude of the roAp stars varies synchronously with the magnetic variation, and the amplitude maximum phase coincides with the magnetic maximum phase. I discuss what kind of information is available and outline how it is deduced from the observational data.2. I 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. I 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, I interpret another peak in the frequency spectrum as an independent quadrupole mode. By this mode identification, I deduce the mass, the evolutionary stage, the rotational frequency, the magnetic field strength, and the geometrical configuration of β Cephei.3. By assuming that RR Lyrae stars have fairly strong dipole magnetic fields with symmetry axis oblique to the rotation axis of the star, I show that the oscillation mode which would be a pure radial oscillation in absence of the magnetic field has a quadrupole component, whose symmetry axis coincides with the magnetic axis. The aspect angle of the quadrupole component changes due to the stellar rotation, and this apparent amplitude variation is interpreted as the Blazhko effect in RR Lyrae stars. It is shown that, in the case of off-axis magnetic field, the phase modulation is expected. I list up some theoretical predictions based on this model, which would observationally examine this hypothesis.