Statistical Ages of M Dwarf Stars from Abundances

比太阳更小、更冷的恒星--被称为M矮星--是宇宙中最常见的恒星类型，但人们对它们的性质知之甚少。了解恒星是如何老化的，对于确定它们的行星如何老化以及这些行星是否能够支持生命至关重要。调查小组将开发一种创新的技术来测量M矮星年龄，使用新的观测和最先进的计算工具。波士顿大学的天文学入门课程将直接涉及学生使用洛厄尔天文台1.8米珀金斯望远镜进行观测的各个方面，一些学生前往亚利桑那州的地点，另一些学生从校园的远程观测中心参加。有了一种测量M矮星精确到10亿年(Gyr)的准确年龄的方法，我们可以开始研究它们的性质如何随着时间的变化而变化。最近对近距离类太阳恒星和遥远巨星的研究表明，恒星年龄、铁丰度和阿尔法丰度之间存在很强的相关性。这种关联适用于0.5 Gyr到13.5 Gyr的年龄，这表明这种关联并不依赖于恒星在银河系中形成的位置。基于这种相关性，铁丰度和α丰度是统计测量附近主序M矮星年龄的工具。拟议的研究计划将通过高分辨率近红外光谱和大气建模实现这些测量。

Stars smaller and cooler than the Sun - those known as M dwarfs - are the most common types of stars in the Universe, but not much is known about their properties. Understanding how stars age is critical for determining how their planets age and whether these planets can support life. The investigating team will develop an innovative technique to measure M dwarf ages, using new observations and state-of-the-art computing tools. Introductory Astronomy courses at Boston University will directly involve students in all aspects of observing using the 1.8-meter Perkins telescope at Lowell Observatory with some students traveling to the Arizona site and others participating from the remote observing center on campus.With a method to measure accurate ages for M dwarf stars to a precision of 1 billion years (Gyr), we can begin to study how their properties change with time. Recent studies of nearby Sun-like stars and distant giant stars show a strong correlation between stellar age, iron abundance, and alpha enrichment. The correlation is valid for ages spanning 0.5 Gyr to 13.5 Gyr, indicating the correlation does not depend on where the stars formed in the Milky Way. Based on this correlation, iron abundance and alpha enrichment are tools for statistically measuring the ages of nearby main-sequence M dwarf stars. The proposed research program will enable these measurements via high-resolution near-infrared spectroscopy and atmospheric modeling.