论文标题
跟上酷星:AB Doradus生活中的一年
Keeping up with the cool stars: One TESS year in the life of AB Doradus
论文作者
论文摘要
通过过渡系外行星调查卫星(TESS)传递的长期,高精度的光度法使我们能够对已知和迄今为止良好的恒星获得新的见解。在本文中,我们介绍了我们对快速旋转器AB Doradus光电活性的TESS研究的结果。由于其在南方的紫外线附近的有利位置,苔丝卫星记录了近600个AB多拉德斯的旋转,并具有高节奏,使我们能够在这款超活动恒星上研究星形和耀斑。旋转调制的观察到的峰值变化近11%,我们发现AB Doradus上的星形斑点显示出高度首选的纵向位置。使用点建模,我们测量了AB Doradus上活性区域的位置,我们发现首选的斑点配置应包括从低至高恒星纬度延伸的大区域。我们将斑点的明显移动解释为差异旋转和斑点演变的结果,并认为典型的点寿命应在10到20天之间。我们进一步发现了AB Doradus的耀斑发生与活性区域在其表面的可见性之间的联系,我们最终使用不同的方法重新计算了恒星的旋转周期,我们将其与先前的确定进行了比较。
The long-term, high precision photometry delivered by the Transiting Exoplanet Survey Satellite (TESS) enables us to gain new insight into known and hitherto well-studied stars. In this paper, we present the result of our TESS study of the photospheric activity of the rapid rotator AB Doradus. Due to its favorable position near the southern ecliptic pole, the TESS satellite recorded almost 600 rotations of AB Doradus with high cadence, allowing us to study starspots and flares on this ultra-active star. The observed peak-to-peak variation of the rotational modulations reaches almost 11 %, and we find that the starspots on AB Doradus show highly preferred longitudinal positions. Using spot modeling, we measured the positions of the active regions on AB Doradus and we find that preferred spot configurations should include large regions extending from low to high stellar latitudes. We interpret the apparent movement of spots as the result of both differential rotation and spot evolution and argue that the typical spot lifetimes should range between 10 and 20 days. We further find a connection between the flare occurrence on AB Doradus and the visibility of the active regions on its surface, and we finally recalculated the star's rotation period using different methods and we compared it with previous determinations.