论文标题
磁循环对恒星突出及其质量损失率的影响
Influence of magnetic cycles on stellar prominences and their mass loss rates
论文作者
论文摘要
快速旋转的酷星的观察通常显示出冠状弹弓突出，从而消除了质量和角动量时。这些突出物的派生质量显示出大约两个数量级的散射。为了研究这种散射是否可以固有，我们使用太阳能图的完整磁性循环来对年轻太阳的冠状结构和突出分布进行建模，在此，根据$ b \ proptoω^{ - 1.32} $，我们将具有角速度的磁化图中的磁场强度扩展。我们重现了观察到的突出质量及其散射。我们表明，田间强度和田间几何形状都有助于可以支持的突出质量以及它们被弹出的速率。预测的突出质量遵循磁性循环，但在一半的周期中，在最大周期和最小循环时达到峰值。我们表明，突出的质量损失率小于恒星风的预测。我们还研究了在典型的恒星磁力图中可能无法解决的小型场的作用。这仅提供了预测的总突出质量的少量降低，主要是通过减少可以支持弹弓突出的大型磁性回路的数量。我们得出的结论是，可以通过潜在的磁循环来解释观察到的突出质量的散射。
Observations of rapidly-rotating cool stars often show coronal slingshot prominences that remove mass and angular momentum when they are ejected. The derived masses of these prominences show a scatter of some two orders of magnitude. In order to investigate if this scatter could be intrinsic, we use a full magnetic cycle of solar magnetograms to model the coronal structure and prominence distribution in a young Sun, where we scale the field strength in the magnetograms with angular velocity according to $ B \propto Ω^{-1.32} $. We reproduce both the observed prominence masses and their scatter. We show that both the field strength and the field geometry contribute to the prominence masses that can be supported and to the rate at which they are ejected. Predicted prominence masses follow the magnetic cycle, but with half the period, peaking both at cycle maximum and at cycle minimum. We show that mass loss rates in prominences are less than those predicted for the stellar wind. We also investigate the role of small-scale field that may be unresolved in typical stellar magnetograms. This provides only a small reduction in the predicted total prominence mass, principally by reducing the number of large magnetic loops that can support slingshot prominences. We conclude that the observed scatter in prominence masses can be explained by underlying magnetic cycles.
