FAST照明口径分析  

Re-investigation of the Illuminated Aperture of the FAST

作　　者：李建玲[1,2,3] 彭勃 柴晓明[1,2] Li Jianling;Peng Bo;Chai Xiaoming(National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China;CAS Key Laboratory of FAST,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家天文台,北京100101 [2]中国科学院FAST重点实验室,北京100101 [3]中国科学院大学,北京100049

出　　处：《天文研究与技术》2021年第3期301-306,共6页Astronomical Research & Technology

基　　金：国家重点研发计划(2018YFA0404703);国家自然科学基金(11703048)资助.

摘　　要：500 m口径球面射电望远镜(Five-hundred-meter Aperture Spherical radio Telescope,FAST)在观测时,将球形反射面内部照明区域的形状变为300 m口径抛物面,实现望远镜的主焦天线功能。照明口径(球面变位到抛物面的口径)对望远镜的观测性能起决定作用。为了望远镜潜在的性能提升及后续发展,在500 m口径球面射电望远镜照明口径300 m及大于300 m的情况下,通过不同焦距抛物面与基准球面变位距离的计算,进行球面到不同口径抛物面变位分析,对望远镜增大照明口径的可行性进行探讨。给出了在500 m口径球面射电望远镜反射面变位驱动促动器最大运动行程范围内,增大口径抛物面变位时抛物面焦距及焦径比的选取。在驱动行程方面初步说明了变位的理论可行性,相关分析同样适用于其他口径的抛物面。The Five-hundred-meter Aperture Spherical radio Telescope(FAST)can change the shape of its illuminated area of the spherical reflector into a paraboloid of 300 m aperture,which realized the primary reflector antenna function of the telescope.The illuminated aperture of the telescope(the aperture of the paraboloid that changed from the spherical reflector)plays a key role in the performance of the telescope.In order to improve the potential performance and for the subsequent development of the telescope,as the illuminated aperture of FAST is 300 m and larger than 300 m,by calculating the shape-changing between paraboloid with different focal lengths and the reference spherical reflector,the analysis of the shape-changing from the spherical reflector to the paraboloid is carried out,and the feasibility of other illuminated aperture for the telescope is discussed.The focal length and the focal ratio of the paraboloid in the maximum movement distance of the actuator are given.In terms of the driving distance,the theoretical feasibility of the shape-changing is explored.The analysis is also applicable to the paraboloid of other apertures.

关 键 词：500 m口径球面射电望远镜 主动反射面 照明口径 变位距离 

分 类 号：TH751[机械工程—仪器科学与技术]