A novel technique using pairs of small telescopes to measure the sizes of nearby stars

亚利桑那州立大学（ASU）的天文学家已经开发出一种新的仪器，可以用来测量明亮恒星的大小，并分离成近对并相互绕轨道运行的恒星。该仪器被称为“干涉仪”，由两个小望远镜组成，当它们一起使用时，就像一个大得多的望远镜。每个望远镜的直径只有50厘米。这些望远镜安装在亚利桑那州立大学地球与空间探索学院的屋顶上。由该项目的首席研究员（PI）和他的学生开发的新相机正在两台望远镜上使用，可以非常快速地拍摄数千张图像。通过仔细研究这些图像序列，研究小组可以检查当行星从恒星前面经过时恒星变暗的情况。该设备还可用于研究被称为“脉冲星”的快速旋转恒星的“闪烁”。通过每月公开展示屋顶干涉仪，计划与业余天文团体合作。该设备还将用于教授研究生和本科生有关该技术和正在使用的专业相机的知识。PI还希望最终将设备带到基特峰天文台，以便在更大的望远镜上进行测试。PI和一名研究生的目标是利用两个或更多的8到18英寸望远镜的强度干涉测量法，获得附近明亮恒星的高角度分辨率观测结果。这些望远镜将与单光子探测器相连，PI和他的学生们已经在他们的实验室里对其进行了表征。主要的科学目标是通过使用多个望远镜观察来自同一颗恒星的单个光子并对它们进行时间标记来测量每颗恒星的角大小。这样就可以获得与望远镜间距大小相对应的角分辨率。测量的恒星半径将与其他恒星特性（如温度）进行比较，以提高我们对主序星对流的理解，并最终得到状态方程。次要科学目标包括解析近距离双星，对已知系外行星凌日的高速光度测定，以及对脉冲星的长期高速监测。组成干涉仪的每个探测器都安装在一个模块中，可以移动到其他望远镜上；该项目的第二阶段是通过光纤电缆将这些单光子计数探测器模块与位于基特峰的更大的（1米和4米）望远镜连接起来。第一阶段——使用亚利桑那州立大学的小型望远镜对干涉仪进行调试——已经开始。

Astronomers at Arizona State University (ASU) have developed a novel new instrument that can be used to measure the size of bright stars and to separate stars that exist as a close pair and orbit each other. Known as an "interferometer", the instrument comprises two small telescopes which, when used together, act like a much larger telescope. Each telescope is only 50 centimeters in diameter. The telescopes are mounted on the roof of the School of Earth and Space Exploration at ASU. New cameras, developed by the project's principal investigator (PI) and his students, are being used on the two telescopes to take many thousands of images very quickly. By studying these sequences of images carefully the team can check for the dimming of the star as a planet passes in front of it. The equipment can also be used to study the "blinking" of very rapidly rotating stars known as "pulsars". Engagement with amateur astronomy communities is planned through monthly public demonstrations of the rooftop interferometer. The equipment will also be used to teach graduate and undergraduate students about the technique and the specialized cameras being used. The PI also hopes to eventually take the equipment to the Kitt Peak Observatory so that it can be tested on larger telescopes. The PI, along with a graduate student, aims to obtain high angular resolution observations of nearby bright stars using intensity interferometry with two or possibly more 8 to 18 inch telescopes. The telescopes will be coupled to single-photon detectors, which the PI and his students have been characterizing in their lab. The main science goal is to measure the angular size of each star by observing single photons from the same star with multiple telescopes and time-tagging them. In this way angular resolutions corresponding to the size of the telescope separations can be achieved. The measured stellar radii will be compared to other stellar properties, such as temperature, to improve our understanding of convection in main sequence stars and ultimately the equation of state. Secondary science goals include resolving close binaries, high-speed photometry of known exoplanet transits, and long-term high-speed monitoring of pulsars. The detectors that comprise the interferometer each fit within a module that can be moved to other telescopes; stage 2 of the project involves coupling these single photon counting detector modules to larger (1 and 4 meter) telescopes at Kitt Peak via fiber-optic cable. Stage 1 - commissioning of the interferometer using the smaller telescopes at Arizona State University - has already begun.