Fundamental Stellar Parameters from the CHARA Array

CHARA 阵列的基本恒星参数

• 批准号: 0908253
• 负责人: Harold McAlister
• 金额: $ 89.41万
• 依托单位: Georgia State University Research Foundation, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0908253&HistoricalAwards=false
• 关键词: Fundamental; Stellar; Parameters; CHARA; Array

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).In this project, Dr. Harold McAlister will continue research in stellar properties using the technique of interferometry. Georgia State University's Center for High Angular Resolution Astronomy (CHARA) operates an optical/near infrared interferometric array on Mount Wilson, California. The CHARA Array has six 1-m aperture telescopes in a Y configuration providing 15 baselines from 33 to 331 meters. In terms of the number and size of its telescopes, the length of its baselines, the broad range of wavelength regimes and spectral resolutions covered by its beam combiners, its imaging capabilities, and broad group of collaborators and users, the CHARA Array is among the most powerful facilities of its type and is unique in the world.Previous publications from CHARA data include: measuring the oblateness and other physical parameters (including gravity darkening) for the rapidly rotating stars Regulus, Alderamin and Vega; detecting the inner-most regions of Vega's circumstellar disk; discovering that cool, low-mass stars of solar composition are larger in diameter for a given mass than lower metal abundance stars of the same mass, suggesting the presence of additional opacity sources not accounted for by current models; measuring the angular separation between the components of the binary star 12 Persei to an accuracy 0.05% of the separation, which significantly improves the accuracy of the masses for the component stars; K band measurements of the angular dimensions of circumstellar disks; a measurement of the diameter of the transiting exoplanet HD 189733b; imaging the surface of the rapidly rotating star Altair, the first time this has been done for a dwarf apart from the Sun.Two newly commissioned beam combiners will leverage the Array's limiting resolution by extending the operating regime from the near IR to the visible region of the spectrum while providing high spectral resolution and improved sensitivity. Broader impact beyond the scientific and intellectual goals exists in three areas. First, CHARA is actively training the next generation of scientific and technical experts in the field of interferometry. A significant fraction of astronomy graduate students at Georgia State University are pursuing their PhD research with the Array. CHARA staff members have participated in many of the NASA/JPL Michelson Summer Schools, and CHARA has published on its website ninety-four Technical Reports available to the international community. Second, CHARA is enhancing science awareness in the large and diverse undergraduate community by incorporating results from the Array in undergraduate astronomy courses, which enroll approximately 700 students per semester. Third, CHARA actively participates in informal science education through such efforts as the collaboration with the American Museum of Natural History as well as through CHARA's own Exhibit Hall located in the CHARA Operations Center on Mount Wilson.

该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。在这个项目中，哈罗德·麦阿里斯特博士将继续使用干涉测量技术对恒星属性进行研究。佐治亚州立大学的高角度分辨率天文中心(CHARA)在加利福尼亚州威尔逊山上运行着一个光学/近红外干涉阵列。查拉阵列有六个Y配置的1米口径望远镜，提供从33米到331米的15条基线。从望远镜的数量和大小、基线的长度、波束合成器覆盖的波长范围和光谱分辨率、成像能力以及广泛的合作者和用户群体来看，Chara阵列是同类设备中最强大的设备之一，在世界上是独一无二的。Chara Data之前发表的出版物包括：测量快速旋转的Regulus、Alderamin和Vega恒星的扁平度和其他物理参数(包括重力变暗)；探测织女星周星盘的最内部区域；发现太阳组成的冷的低质量恒星的直径比相同质量的低金属丰度恒星大，这表明存在当前模型无法解释的额外不透明度来源；测量双星12英仙座各组成部分之间的角分离，其精度为分离的0.05%，这显著提高了组成恒星的质量的精度；K波段测量了绕星盘的角尺寸；测量了凌日系外行星HD 189733b的直径；成像快速旋转的恒星牛郎星的表面，这是第一次对太阳以外的矮星进行成像。两个新投入使用的波束合成器将利用阵列的有限分辨率，将工作区域从近红外扩展到光谱的可见区域，同时提供高光谱分辨率和更高的灵敏度。超越科学和智力目标的更广泛的影响存在于三个领域。首先，查拉正在积极培养干涉测量领域的下一代科技专家。佐治亚州立大学的天文学研究生中有很大一部分正在攻读天文学博士学位。CHARA的工作人员参加了NASA/喷气推进实验室迈克尔逊暑期学校的许多活动，CHARA在其网站上发布了94份可供国际社会使用的技术报告。其次，Chara正在通过将阵列的结果纳入本科天文学课程来提高广大和多样化的本科生社区的科学意识，该课程每学期招收约700名学生。第三，Chara通过与美国自然历史博物馆合作以及通过位于威尔逊山Chara运营中心的Chara自己的展览馆等努力，积极参与非正式科学教育。