太阳远紫外在临近空间的辐射特性研究  

Study on Solar FUV Radiation Characteristics in Near Space

作　　者：张轩谊 韦飞 彭松武 冯鹏远 冷双 ZHANG Xuan-yi;WEI Fei;PENG Song-wu;FENG Peng-yuan;LENG Shuang(National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Beijing Key Laboratory of Space Environment Exploration,Beijing 100190,China)

机构地区：[1]中国科学院国家空间科学中心,北京100190 [2]中国科学院大学,北京100049 [3]天基空间环境探测北京市重点实验室,北京100190

出　　处：《光谱学与光谱分析》2023年第2期374-382,共9页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(41974211);中国科学院战略先导科学专项(XDA17010201);北京市科技委培育项目(Z201100003520005)资助。

摘　　要：太阳远紫外辐射是临近空间能量输入的主要来源之一,临近空间环境对太阳爆发活动的响应是有待深化研究的重要科学问题。对太阳远紫外在中高层大气的辐射特性进行研究,是研究临近空间大气成分与密度变化、光化学反应以及动力学过程的重要基础。利用FISM2耀斑模型计算的远紫外数据和MSIS-E-00模型提供的地球中高层大气数据,将120~190 nm的太阳远紫外辐射分为7段,使用基于Lambert-Beer定律的大气辐射传输方法进行数值模拟。选取2010年1月至2020年12月共11年间的150组耀斑数据,利用时间滞后互相关(TLCC)评估了太阳远紫外辐射和软X射线的耀斑峰值时间差,使用最小二乘法(LS)计算了二者的耀斑峰值流量关系,然后利用大气辐射传输方法计算了耀斑爆发时太阳远紫外在临近空间(20~100 km)的光谱特性、流量变化以及加热率变化,最后计算了太阳远紫外辐射在地球大气中的沉积情况。计算结果表明,在太阳耀斑爆发过程中,远紫外辐射的流量出现明显变化,流量峰值比软X射线提前240 s左右;远紫外辐射与软X射线的流量峰值近似线性相关,大于140 nm波段的系数随波长的增加而增大;在20~100 km的临近空间范围,太阳远紫外光谱几乎被完全吸收,但由于大气成分特殊的吸收窗口结构,185~190 nm波段的部分光谱可到达20 km高度;临近空间区域内,太阳耀斑爆发时与爆发前的远紫外流量比值在7个波段均为2.0左右,峰值加热率的比值分别为1.22,1.88,1.35,1.42,1.23,1.08和1.11。验证了在临近空间利用远紫外辐射感知太阳耀斑的可行性,为临近空间光学探测实验提供理论依据,为大气反演等相关研究领域提供参考。Solar far-ultraviolet radiation is one of the main sources of energy input into near space,and the response of the near space environment to solar eruptions is an important scientific issue to be further studied.Studying the radiation characteristics of the solar far-ultraviolet in the middle and upper atmosphere is an important basis for studying atmospheric composition and density changes,photochemical reactions and dynamic processes in near space.In this paper,using the far-ultraviolet data calculated by the FISM2 flare model and the earth’s middle and upper atmosphere data provided by the MSIS-E-00 model,the solar far-ultraviolet radiation from 120 to 190 nm is divided into 7 bands,and numerical simulations were performed using an atmospheric radiative transfer method based on the Lambert-Beer law.A total of 150 sets of flare data in 11 years from January 2010 to December 2020 were selected,and time-lag cross-correlation(TLCC)was used to evaluate the flare peak time difference between solar far-ultraviolet radiation and soft X-rays,using least squares(LS)method to calculate their flare peak flow relationship.Atmospheric radiative transfer equations were used to calculate the spectral properties,flux changes,and heating rate changes of the solar far-ultraviolet in near space(20~100 km)during flares.Finally,the deposition of solar far-ultraviolet radiation in the earth’s atmosphere is calculated.The results show that in the process of solar flare eruption,the flux of far-ultraviolet radiation changes significantly,and the flux peak is about 240 s earlier than that of soft X-rays.The wavelength increases with the increase of the wavelength;in the near space range of 20~100 km,the solar far-ultraviolet spectrum is almost completely absorbed,but due to the special absorption window structure of the atmospheric composition,part of the spectrum in the 185~190 nm band can reach an altitude of 20 km.In the near space region,the ratios of the far-ultraviolet fluxes at the time of the solar flare eruption and before

关 键 词：临近空间 太阳耀斑 远紫外 辐射传输 大气吸收 

分 类 号：O434.2[机械工程—光学工程]