Stellar and Solar Magnetic Activity Cycles

利用洛厄尔天文台1.1 m望远镜上的专用高色散光纤馈送光谱仪设备，我们建议研究恒星/太阳磁周期和色球活动。光谱仪使用CCD探测器记录了太阳型恒星和太阳本身在K线（3933）和红外三重态（8542）以及h（6563）的谱线轮廓，使用相同的仪器观测到的只是另一颗恒星。这些观测的目的是利用恒星周期作为研究太阳周期的工具。从周期形态（振幅、形状、规律性）作为恒星质量、年龄、自转速率、化学成分等的函数的详细研究中，我们可能希望：(a)推断出像太阳这样的恒星在其整个生命周期中的周期行为的时间历史，包括主要偏离“正常”行为（例如，蒙德极小值）的统计频率；(b)获得可能的周期总集合的广阔视角，从而深入了解恒星发电机的性质和恒星磁性的最终起源。恒星周期提供了从太阳本身观测中无法获得的补充信息，但对理解太阳周期至关重要。

Using a dedicated high-dispersion fiber-fed spectrograph facility at the 1.1-m telescope of Lowell Observatory, we propose to study stellar/solar magnetic cycles and chromospheric activity The spectrograph records, using CCD detectors, the line profiles of Ca II at the K line (3933 ) and the infrared triplet (8542 ), and H. (6563 ) for solar-type stars and for the Sun itself, observed as just another star using the same instrument. The purpose of these observations is to use stellar cycles as tools to study the solar cycle. From detailed studies of cycle morphology (amplitude, shape, regularity) as a function of stellar mass, age, rotation rate, chemical composition, etc., we may hope to: (a) Infer the time-history of cyclic behavior for a star like the Sun over its entire lifetime, including information about the statistical frequency of major departures from "normal" behavior (e.g., Maunder minima); and (b) Obtain a broad perspective of the total ensemble of cycles possible, hence gain deep insight into the nature of stellar dynamos and into the ultimate origins of stellar magnetism. Stellar cycles provide complementary information unobtainable from observations of the Sun itself but of crucial importance to understanding the solar cycle.