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恒星XX三角的长期多普勒成像表明混乱的非周期动力发电机
K G Strassmeier1,2, Zs Kővári3,4, M Weber5
1Leibniz-Institute for Astrophysics Potsdam (AIP), D-14482, Potsdam, Germany. kstrassmeier@aip.de.
Nature communications
|December 5, 2024
概括
这项研究使用多普勒成像来追踪XX三角形上的星点16年. 这是一颗星星.
科学领域:
- 恒星天体物理学 恒星天体物理学
- 太阳物理 太阳物理
- 探测系外行星的探测器
背景情况:
- 太阳黑子是我们太阳上可以观察到的磁现象,与其内部动力发电机有关.
- 星斑与其他恒星上的太阳斑相似,但直接地表成像具有挑战性.
- 多普勒成像为绘制恒星表面特征提供了一种间接方法.
研究的目的:
- 为了研究XX三角星上的星斑的长期演变.
- 分析恒星光中心的移位及其与活动周期的潜在关系.
- 评估恒星旋转对天文系外行星探测的影响.
主要方法:
- 利用多普勒成像创建了XX三角形的99个独立的表面图像.
- 将图像组合到一个时间序列电影中,可视化16年的点进化.
- 从成像数据中重建了恒星盘的光中心位移.
主要成果:
- 观测到恒星盘光中心的显著移位 (高达24微秒).
- 没有发现太阳类似周期性行为的证据,表明活动周期.
- 这颗恒星的动力发电机看起来很混乱,没有周期.
结论:
- 恒星XX三角形表现出一个混乱的恒星动力发电机,与太阳的周期周期不同.
- 旋转诱导的光中心变化对天文计外行星搜索具有根本的限制.
- 长期监测恒星斑的演变对于理解恒星磁性活动至关重要.
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