基于丽江10 cm日冕仪的镜面尘埃杂散光研究  

Stray Light by Dust on Objective Surface Based on Lijiang 10 cm Coronagraph

作　　者：沙飞扬 刘煜[1,2,4] 张雪飞 宋腾飞[1,4] 张洪起 王永峰[1] 孙明哲 SHA Feiyang;LIU Yu;ZHANG Xuefei;SONG Tengfei;ZHANG Hongqi;WANG Yongfeng;SUN Mingzhe(Yunnan Observatories,Chinese Academy of Sciences,Kunming 650215,China;School of Physical Science and Technology,Southwest Jiaotong University,Chengdu 610031,China;School of Astronomy and Space Science,University of Chinese Academy of Sciences,Beijing 101408,China;Yunnan Key Laboratory of Solar Physics and Space Science,Kunming 650011,China;National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China;Shandong University at Weihai,Weihai 264209,China)

机构地区：[1]中国科学院云南天文台,昆明650215 [2]西南交通大学物理科学与技术学院,成都610031 [3]中国科学院大学天文与空间科学学院,北京101408 [4]云南省太阳物理与空间目标监测重点实验室,昆明650011 [5]中国科学院国家天文台,北京100101 [6]山东大学(威海),威海264209

出　　处：《光子学报》2023年第5期172-184,共13页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.12173086,41904168,42274227)。

摘　　要：利用云南天文台丽江10 cm日冕仪绿线成像系统研究了物镜表面尘埃量级与其造成的散射杂散光强度的关系,获得了散射光随日心距离的分布规律,并对日冕图像进行了修正。得到了不含尘埃散射杂散光背景的日冕图像,提高了数据质量。本文研究有助于研究日冕强度、结构变化趋势,也有助于理解日冕仪内部其他杂散光源,助力我国未来大口径日冕仪的研发。The solar corona is the outermost layer of the solar atmosphere,consisting of thin,highly ionized and hot plasma.In visible light,the solar corona is much dimmer than the photosphere,only one millionth as bright,so it is not visible in daylight.The only exception is during a total solar eclipse,when the moon blocks the light from the photosphere completely and reveals the corona.The coronagraph is a special telescope that can observe the solar corona even in the absence of a total solar eclipse.It creates an artificial eclipse by using an occulter to block the bright photosphere.Depending on the location of the occulter,there are two main types of coronagraphs:externally occulted and internally occulted.The externally occulted coronagraph blocks the direct sunlight with an occulter in front of the objective lens,but it also causes some vignetting in the field of view,which affects the quality of the observations.The internally occulted coronagraph has the occulter behind the objective lens,however,this means that some parts of the telescope,such as the objective lens and the tube,are exposed to direct sunlight and produce a lot of stray light,which needs to be strictly suppressed.The stray light of the internally occulted coronagraph can be divided into two parts:fixed and variable.The former does not change with time and environmental cleanliness,while the latter increases with decreasing environmental cleanliness.For the ground-based internally occulted coronagraph with regular observations,the scattering from dust on the objective surface is the variable stray light,as the dust continues to accumulate on the surface.Although the accumulation can be slowed down by frequent cleaning of the objective surface and the level of this stray light can be suppressed,the objective surface cannot be guaranteed to remain clean throughout the observation due to weather,atmospheric particle pollution and other factors.More importantly,this approach is somewhat subjective,as the observer cannot directly assess the current lev

关 键 词：日冕仪 YOGIS 杂散光 尘埃 散射 

分 类 号：P182.62[天文地球—天文学]