A Leap in Sensitivity for CHARA/CLASSIC Optical Interferometry for Astronomy

天文学 CHARA/CLASSIC 光学干涉测量灵敏度的飞跃

• 批准号: 1909858
• 负责人: Theo ten Brummelaar
• 金额: $ 132.77万
• 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: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909858&HistoricalAwards=false
• 关键词: Leap; Sensitivity; CHARA; CLASSIC; Optical

Optical interferometry uses an array of smaller telescopes connected together to achieve the angular resolution of telescopes many hundreds of meters across. Such interferometers have the resolution of extremely large telescopes but have the sensitivity of small telescopes. They can see stars in exquisite detail but can so far only see relatively bright stars. The main goal of this project is to improve the sensitivity of one of these interferometers called the Center for High Angular Resolution Astronomy (CHARA) Array, which is located at Mount Wilson Observatory. Renovations to the camera, optical glass, and data recording will enable studying stars 10 times fainter than currently possible. Such improved sensitivity will enable investigations that may inform whether life may exist elsewhere in the universe, and open up new areas of research. This program will also include new facilities in the CHARA visitor center, which hosts 15,000 visitors each year, and a collaboration with the American Museum of Natural History to display current science bulletins at the CHARA visitor center.The CHARA Array longest baseline yields angular diameter measurements as small as 0.7 mas in K band improving to 0.2 mas at R. CHARA can resolve stellar disks all along the main sequence from O- to M-types, whereas there will be no main sequence stars resolvable by the next generation of single aperture telescopes. The most significant problem in ground based interferometry is sensitivity. This program will increase the limit of the CLASSIC/CLIMB beam combiner by 2 magnitudes in the near infrared. This will be achieved by replacing the 20-year-old PICNIC detector with a modern SELEX MOVPE SAPHIRA based detection system. This upgrade will also include spectral resolution in both H and K bands, simultaneous observation in both bands, and a polarization split. With enhanced sensitivity it will be possible to survey a much broader range of stellar diameters and temperatures, the disks around young stars, winds from massive stars, interacting and detached binary stars, transient events, as well as open up new opportunities for guest observers through the community access program funded by NSF/MSIP. More sensitivity will also vastly expand the ability to observe the cores of Active Galactic Nuclei (AGN). The CHARA could directly confirm or deny a binary structure in an AGN core for the first time.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

光学干涉测量法使用一系列连接在一起的较小望远镜来实现数百米直径的望远镜的角分辨率。 这种干涉仪具有极大望远镜的分辨率，但具有小型望远镜的灵敏度。他们可以看到星星的精致细节，但到目前为止只能看到相对明亮的星星。该项目的主要目标是提高位于威尔逊山天文台的高角分辨率天文学中心 (CHARA) 阵列干涉仪之一的灵敏度。对相机、光学玻璃和数据记录的革新将使研究恒星的亮度比目前暗淡十倍。这种灵敏度的提高将使研究能够确定宇宙其他地方是否存在生命，并开辟新的研究领域。该计划还将包括每年接待 15,000 名游客的 CHARA 游客中心的新设施，以及与美国自然历史博物馆的合作，在 CHARA 游客中心展示当前的科学公告。CHARA 阵列最长基线可产生角直径测量值K 波段小至 0.7 mas，在 R 波段提高到 0.2 mas。CHARA 可以解析沿主序带从 O 型到 M 型的恒星盘，而不会有下一代单孔径望远镜可分辨主序星。地基干涉测量中最重要的问题是灵敏度。该计划将使 CLASSIC/CLIMB 光束组合器在近红外范围内的限制提高 2 个数量级。这将通过用基于 SELEX MOVPE SAPHIRA 的现代检测系统替换已有 20 年历史的 PICNIC 检测器来实现。此次升级还将包括 H 和 K 波段的光谱分辨率、两个波段的同步观测以及偏振分裂。随着灵敏度的提高，将有可能调查更广泛的恒星直径和温度、年轻恒星周围的圆盘、来自大质量恒星的风、相互作用和分离的双星、瞬态事件，并为客座观察者开辟新的机会由 NSF/MSIP 资助的社区访问计划。更高的灵敏度还将极大地扩展观察活动星系核（AGN）核心的能力。 CHARA 首次可以直接确认或否认 AGN 核心中的二元结构。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。