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在T Tauri恒星的磁盘中空间解析的磁场结构
Ian W Stephens1, Leslie W Looney2, Woojin Kwon3
11] Institute for Astrophysical Research, Boston University, Boston, Massachusetts 02215, USA [2] Department of Astronomy, University of Illinois, Urbana, Illinois 61801, USA.
Nature
|October 23, 2014
概括
年轻恒星积聚盘中的磁场至关重要,但人们对其了解甚少. 对HL Tau的新观测显示,磁场与磁盘对齐.
科学领域:
- * 天文学和天体物理学
- * 恒星的形成和进化
- * 等离子体物理学
背景情况:
- * 磁场在恒星形成期间的积累盘中是必不可少的,但它们的强度和结构在观测上仍然受到很小的约束.
- *以前的研究推断T Tauri恒星和内部磁盘的磁场强度,但磁盘磁场的大部分并未直接观察到.
- *理论模型预测状,极状或混合磁场配置,影响年轻恒星盘中的角运动量传输.
研究的目的:
- * 为了研究年轻恒星HL Tau.盘中的磁场强度和形态.
- * 用空间解析极化辐射来绘制磁场结构的地图.
- * 将观测结果与理论预测对积累盘中的磁场进行比较.
主要方法:
- *使用了来自HL Tau盘的1.25毫米极化连续辐射的分辨测量结果.
- *分析了极化数据,以推断大约80个天文单位的磁场方向和强度.
- * 将观察到的磁场形态与理论模型进行比较.
主要成果:
- * HL Tau盘内的80天文单位尺度上的磁场与磁盘的主要轴相吻合.
- * 这种观察到的对齐表明磁场在这个尺度上没有垂直元件主导.
- *纯粹的圆形磁场模型不能充分解释观察到的数据.
结论:
- * HL陶磁盘中的磁场形态是意想不到的,比目前的理论模型表明的更复杂.
- *这些发现挑战了关于磁场在年轻恒星积聚过程中的作用和结构的现有理论.
- *需要进一步的理论发展才能充分理解磁场对恒星和行星形成的影响.
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