在太阳对流区底部的动态变化
Howe1, Christensen-Dalsgaard, Hill
1National Solar Observatory, National Optical Astronomy Observatories, Post Office Box 26732, Tucson, AZ 85726-6732, USA. Theoretical Astrophysics Center, Danish National Research Foundation, and Institute of Physics and Astronomy, Aarhus Uni.
概括
科学家们观察到太阳在太阳底部附近的旋转变化,发现低度的1.3年变化. 这些发现为太阳动力发电机提供了洞察力,可能解释太阳的磁性活动周期.
科学领域:
- 太阳物理 太阳物理
- 太阳地震学 (Helioseismology) 是一个关于太阳的学科.
- 天体物理学 天体物理学
背景情况:
- 太阳的内部旋转会影响它的磁性活动周期.
- 了解旋转动力学是模拟太阳能发动机的关键.
- 之前的研究缺乏对太阳内部深层旋转的详细测量.
研究的目的:
- 为了检测和量化太阳内部旋转的时间变化.
- 为了研究塔科克林附近的旋转变化,这是对流和辐射区域之间的边界.
- 探索内部旋转变化与太阳能发电机之间的联系.
主要方法:
- 通过几乎连续地观察太阳振荡模式,利用太阳地震探测.
- 采用两个互补的实验设置来获取数据.
- 逆转全球模式的频率分割以确定角速度 (Omega).
主要成果:
- 在阳光旋转的显著时间变化 (高达6nHz) 在对流的底部附近检测到.
- 在低度观察到一个突出的1.3年周期的旋转变化.
- 发现旋转变化在赤道和高度附近最为明显,在塔科克林上方和下方.
结论:
- 检测到的旋转变化发生在太阳能动力发电机的假定位置附近.
- 这些变化相对于穿过塔科克线的角速度的辐射梯度而言是实质性的.
- 研究结果表明,内部旋转动力学与太阳22年磁活动周期的产生之间存在联系.
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