How Binary Companion Stars Impact Stellar Rotational Evolution

斯蒂芬妮·道格拉斯被授予NSF天文学和天体物理奖学金，以在哈佛-史密森天体物理中心开展一项研究和教育计划。道格拉斯将观测数百颗双星(相互环绕的恒星)，以测量它们的物理性质。这将使我们更好地了解恒星-以及它们对行星的影响-是如何随时间变化的。除了这项研究，道格拉斯还将为来自社会经济贫困背景的中学生和来自科学代表性不足群体的本科生提供天文学研究体验。道格拉斯将研究恒星自转周期与伴星距离之间的关系。对疏散星团的观测表明，在给定年龄的恒星中，快速自转的恒星往往是双星。这可能是因为超过0.01-100亿年的潮汐效应，或者是在最初的1000万年里，双星和原行星盘之间的相互作用。这两种效应都会导致双星的自转速度快于单星，从而影响双星系统中的角动量演化。道格拉斯将结合自转周期和双星轨道参数来解释为什么快速自转的恒星往往是双星。道格拉斯将使用光度学、光谱学和光曲线来确定候选双星，以及新的径向速度观测来测量轨道。这些数据将使她能够测试双星伴星如何随着时间的推移影响恒星自转。对于她工作的教育部分，道格拉斯将开发基于探究的活动，向中学生介绍双星和系外行星研究。她还将为来自代表性不足背景的本科生提供与双星和系外行星研究相关的项目方面的建议。

Stephanie Douglas is awarded an NSF Astronomy and Astrophysics Fellowship to conduct a program of research and education at the Harvard-Smithsonian Center for Astrophysics. Douglas will observe hundreds of binary stars (stars that orbit each other) to measure their physical properties. This will allow a better understanding of how stars---and their effects on planets---change with time. Alongside this research, Douglas will provide astronomy research experiences to middle school students from socioeconomically disadvantaged backgrounds and to undergraduate students from groups underrepresented in science. Douglas will study the relationship between a star's rotation period and the proximity of a companion. Observations of open clusters show that among stars of a given age, the rapid rotators tend to be binaries. This could be because of tidal effects acting over 0.01 - 10 billion years or interactions between the binary companion and the protoplanetary disk during the first 10 million years. Both effects would cause binary stars to rotate faster than single stars, thus affecting angular momentum evolution in the binary systems. Douglas will combine rotation periods and binary orbital parameters to explain why rapidly rotating stars tend to be binaries. Douglas will use photometry, spectroscopy, and light curves to identify candidate binaries as well as new radial velocity observations to measure orbits. These data will allow her to test how binary companions affect stellar rotation over time. For the educational component of her work, Douglas will develop inquiry-based activities to introduce middle school students to binary and exoplanet research. She will also advise undergraduate students from underrepresented backgrounds on projects related to binary and exoplanet research.