论文标题
上城狼疮中低质量星和苔丝的下城crux的旋转
Rotation of Low-Mass Stars in Upper Centaurus Lupus and Lower Centaurus Crux with TESS
论文作者
论文摘要
我们提出了恒星旋转速率，这些旋转速率来自上半人马座 - 卢普斯（UCL; 〜136 pc，〜16 Myr）和下半人马座（LCC; 〜115 pc; 〜115 pc，〜17 Myr）的恒星的恒星光曲线。我们发现约90％成员的斑点调制期（P）。光曲线和周期图的范围呼应了针对具有K2的其他群集发现的，但较少的多周期星的范围可能表明苔丝的噪声特征不同，或者是此处源选择方法的结果。对于K2观察到的老年和年轻群集，P的分布与质量的颜色函数非常适合在此之间，在这里探测的最高和最低质量中都发现了快速旋转器，并且M Star旋转速率的组织分布良好。大约13％的恒星具有过量的红外（IR）过量，表明有脉络膜磁盘；考虑到星星的年龄，这与期望很匹配。在p〜2天时，有明显的磁盘恒星堆积，随着质量减少，堆积可能会变短。在P〜2天，也有很大的无磁盘M恒星，这暗示了这些恒星最近已经从磁盘中释放出来了。探索UCL/LCC中恒星的旋转速率有可能帮助我们了解磁盘对旋转的影响的开始，以及恒星对解锁响应的时间尺度。
We present stellar rotation rates derived from Transiting Exoplanet Survey Satellite (TESS) light curves for stars in Upper Centaurus-Lupus (UCL; ~136 pc, ~16 Myr) and Lower Centaurus-Crux (LCC; ~115 pc, ~17 Myr). We find spot-modulated periods (P) for ~90% of members. The range of light curve and periodogram shapes echoes that found for other clusters with K2, but fewer multi-period stars may be an indication of different noise characteristics of TESS, or a result of the source selection methods here. The distribution of P as a function of color as a proxy for mass fits nicely in between that for both older and younger clusters observed by K2, with fast rotators found among both the highest and lowest masses probed here, and a well-organized distribution of M star rotation rates. About 13% of the stars have an infrared (IR) excess, suggesting a circumstellar disk; this is well-matched to expectations, given the age of the stars. There is an obvious pile-up of disked M stars at P~2 days, and the pile-up may move to shorter P as the mass decreases. There is also a strong concentration of disk-free M stars at P~2 days, hinting that perhaps these stars have recently freed themselves from their disks. Exploring the rotation rates of stars in UCL/LCC has the potential to help us understand the beginning of the end of the influence of disks on rotation, and the timescale on which the star responds to unlocking.
