Non-radial Stellar Oscillations
Non-radial Stellar Oscillations
复制标题
非径向恒星振荡
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
A. Weiss
中科院分区：
文献类型：
--
作者：
R. Kippenhahn;A. Weigert;A. Weiss
我们使用球坐标r，r，r，r，用一个矢量v来描述质量元素的速度，矢量v的分量为v r，v r，v r，v r。对于前面几节所讨论的径向脉动，速度只有一个非零分量v r，它只取决于r。这是一种如此特殊的运动，以至于人们可能会想，为什么一颗星星会喜欢以这种方式振荡。事实上，很容易想象非球对称扰动的发生，例如那些与湍流运动或局部温度波动有关的扰动。它们可以导致非径向振荡，即振荡运动通常具有非零分量v r、v、v，所有这些分量都可以取决于r、v和v。显然，对更一般的非径向振荡的处理比径向振荡的处理复杂得多，但它们在观测到的现象中确实起着作用（见§40.4）。我们将仅限于指出最简单情况下的几个性质：小（线性）、绝热、极轴模振荡。更详细的情况见考克斯（1976年，1980年），UNNO等（1979年）。
We use spherical coordinates r, ϑ, ϕ and describe the velocity of a mass element by a vector v having the components v r , v ϑ , v ϕ . For the radial pulsations treated in the foregoing sections, the velocity has only one non-vanishing component, v r , which depends only on r. This is so specialized a motion that one might wonder why a star should prefer to oscillate this way at all. In fact it is easier to imagine the occurrence of perturbations that are not spherically symmetric, for example those connected with turbulent motions or local temperature fluctuations. They can lead to non-radial oscillations, i.e. oscillatory motions having in general non-vanishing components v r , v ϑ , v ϕ , all of which can depend on r, ϑ, and ϕ. It is obvious that the treatment of the more general non-radial oscillations is much more involved than that of the radial case, but they certainly play a role in observed phenomena (see §40.4). We will limit ourselves to indicating a few properties of the simplest case: small (linear), adiabatic, poloidal-mode oscillations. For more details see, for instance, COX (1976, 1980), UNNO et al. (1979).