Mechanical equilibrium of hot, large-scale magnetic loops on T Tauri stars TTS magnetic loops
Mechanical equilibrium of hot, large-scale magnetic loops on T Tauri stars TTS magnetic loops
复制标题
金牛座 T 星上热大尺度磁环的机械平衡 TTS 磁环
DOI：
10.1111/j.1365-2966.2012.20434.x
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发表时间：
2012
影响因子：
4.8
通讯作者：
Aarnio A
中科院分区：
文献类型：
--
作者：
Aarnio A
金牛座T星上推断出的最广泛的闭合磁环将炽热的X射线发射等离子体限制在距离恒星表面超过X射线明亮的日冕和闭合的大尺度场的距离上，距离与共转半径相当。机械平衡模型已经表明，密集的凝结，或“弹弓凝结”，可以上升到很高的高度，因为它们的密度和温度比它们的环境低。然而，在金牛T星上，我们探测到的等离子体温度高于周围的日冕温度。根据先前的模型结果，这些环不应该达到数十个恒星半径的推断高度，在那里它们可能不再有外部磁场的支持来对抗磁张力。在这项工作中，我们考虑的恒星风的影响，并表明，确实是负浮力的热环可以达到机械平衡的高度以上的典型程度的封闭日冕和共转半径。
The most extended, closed magnetic loops inferred on T Tauri stars confine hot, X-ray-emitting plasma at distances from the stellar surface beyond the X-ray-bright corona and closed large-scale field, distances comparable to the corotation radius. Mechanical equilibrium models have shown that dense condensations, or ‘slingshot prominences’, can rise to great heights due to their density and temperatures cooler than their environs. On T Tauri stars, however, we detect plasma at temperatures hotter than the ambient coronal temperature. By previous model results, these loops should not reach the inferred heights of tens of stellar radii where they likely no longer have the support of the external field against magnetic tension. In this work, we consider the effects of a stellar wind and show that indeed hot loops that are negatively buoyant can attain a mechanical equilibrium at heights above the typical extent of the closed corona and the corotation radius.