Stars and Brown Dwarfs: RECONS Studies of the Solar Neighborhood

恒星和褐矮星：太阳邻域的勘测研究

• 批准号: 1412026
• 负责人: Todd Henry
• 金额: $ 48.11万
• 依托单位: Georgia State University Research Foundation, Inc.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1412026&HistoricalAwards=false
• 关键词: Stars; Brown; Dwarfs; RECONS; Studies

The RECONS (REsearch Consortium On Nearby Stars) project is making a reconnaissance of the nearest stars to the Sun, focusing on our neighbors out to a horizon of about 80 light years. In the current effort, the team is focusing on the smallest stars, known as red dwarfs, and their slightly less massive cousins, the brown dwarfs. The main difference between the two types of objects is whether or not they can shine via nuclear reactions. Red dwarfs are true stars that fuse hydrogen into helium in their cores, like our Sun, and shine for many billions of years. Although they are the smallest true stars in the Universe, the red dwarfs are by far the most common type of star, accounting for at least three-quarters of all stars, but we're not quite sure how many there are. On the other hand, brown dwarfs are cooling bodies like Jupiter that do not fuse hydrogen, and behave more like superplanets. The RECONS team is taking a census of red and brown dwarfs and revealing how often they are orbited by stellar, brown dwarf, or planetary companions. We will then ultimately know just what fraction of the Sun's neighbors are stars and where some of the nearest planets are found. Through this program, specialized training in astrometry - the precise measurement of positions and motions on the sky - will be provided to Georgia State University students. As a large minority-serving institution, Georgia State well placed to provide research opportunities to students from underrepresented groups. The program will also involve graduate and undergraduate students in all aspects of the research, and they will share their results with the general public through their website (www.recons.org) and through public outreach activities.RECONS is a long-term, NSF-supported program to characterize the astronomical objects closest to the Sun. Most of these are M dwarfs and Brown Dwarfs. Among the many studies enabled by this program is a detailed description of how the mass and luminosity functions transition between fusion-powered stars and the non-stellar dwarfs. The RECONS catalog, publicly-available at their website, also provides the best estimate available for the relative populations of late-type stars and brown dwarfs. In this proposal, they will extend the volume of space completely sampled, extend their 20-year timeline of astrometric measurements, and map orbits of low-mass binaries (including those with planetary companions).

RECONS（邻近恒星研究联盟）项目正在对距离太阳最近的恒星进行侦察，重点关注地平线约 80 光年之外的邻居恒星。 在目前的工作中，该团队的重点是最小的恒星，即红矮星，以及它们质量稍小的表兄弟，即棕矮星。这两类物体之间的主要区别在于它们是否可以通过核反应发光。 红矮星是真正的恒星，它们在其核心将氢融合成氦，就像我们的太阳一样，并且可以发光数十亿年。 尽管它们是宇宙中最小的真正恒星，但红矮星是迄今为止最常见的恒星类型，至少占所有恒星的四分之三，但我们不太确定有多少。另一方面，褐矮星是像木星一样的冷却天体，不会融合氢，并且表现得更像超级行星。 RECONS 团队正在对红矮星和棕矮星进行普查，并揭示它们被恒星、棕矮星或行星伴星环绕的频率。 然后我们最终将知道太阳的邻居中有多少是恒星，以及最近的一些行星在哪里。 通过该计划，将为佐治亚州立大学的学生提供天体测量学（天空位置和运动的精确测量）方面的专门培训。 作为一所大型的少数族裔服务机构，佐治亚州立大学完全有能力为来自弱势群体的学生提供研究机会。 该计划还将让研究生和本科生参与研究的各个方面，他们将通过其网站 (www.recons.org) 和公共外展活动与公众分享他们的结果。RECONS 是一项由 NSF 支持的长期计划，旨在描述最接近太阳的天体的特征。 其中大部分是 M 矮星和棕矮星。 该计划开展的众多研究之一详细描述了质量和光度函数如何在聚变驱动的恒星和非恒星矮星之间转变。 RECONS 目录可在其网站上公开获取，还提供了晚型恒星和褐矮星相对数量的最佳估计。 在这项提案中，他们将扩大完全采样的空间体积，延长天体测量测量的 20 年时间表，并绘制低质量双星（包括具有行星伴星的双星）的轨道图。