太阳极区冕洞内小尺度结构的紫外光谱研究  

Ultraviolet Spectroscopic Study on the Fine Structures in the Solar Polar Hole

作　　者：章敏[1,2] 王东[1] 刘果红[1] 

机构地区：[1]安徽建筑大学数理学院,安徽合肥230601 [2]中国科学技术大学地球与空间科学学院、中国科学院近地空间环境重点实验室,安徽合肥230026

出　　处：《光谱学与光谱分析》2014年第7期1890-1893,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(41304134);安徽省优秀青年人才基金重点项目(2013SQRL044ZD);安徽建筑大学博士基金项目(K02654)资助

摘　　要：SOHO/SUMER太阳紫外光谱仪的N Ⅳ谱线观测到太阳南极区冕洞内存在许多小尺度结构，其空间尺度约1～几角秒，寿命尺度约1～几min。小尺度结构沿狭缝方向呈条状，视向多普勒速度可至几十km · s-1。在有的南极区冕洞区域内，小尺度结构的视向多普勒速度呈红、蓝移准周期性交错分布，持续时间长达100 min。部分小尺度结构在同一观测窗口的高温 Ne ⅤⅢ谱线还可清晰显现。有的小尺度结构在Ne ⅤⅢ速度演化图的时间和位置与N Ⅳ谱线速度图基本一致，但它们在Ne ⅤⅢ速度演化图中更延展和弥散。N Ⅳ紫外光谱显示部分小尺度结构谱线呈现非高斯形状，谱线两翼速度可达150 km · s-1，与太阳过渡区爆发事件的光谱特征相似。太阳过渡区爆发事件常出现在宁静区，SOHO/SUMER太阳紫外光谱仪的NⅣ谱线显示在南极区冕洞也可产生爆发事件，且具有较强的动力学特征。Fine structures in the south solar polar coronal hole were observed by N Ⅳ line of SOHO/SUMER spectrograph .The scales of the fine structures range spatially range from 1 arcsec to several arcsecs ,temporally from 1 min to several minutes ,and parts of them are in strip shape along the slit direction .The line-of-sight velocity of them is up to tens of km · s-1 with red and blue shift intercrossed occasionally ,which appear periodically as long as 100 minutes in some regions .Part of the fine structures can be clearly observed at the Ne Ⅴ Ⅲ line with higher formation temperature in the same spectral window .The time and location of some fine structures with high velocity in the Ne Ⅴ Ⅲ spectrum are almost the same as that in N Ⅳ spectrum ,but they are extended and diffused in the Ne Ⅴ Ⅲ spectrum .Some fine structures have non-Gaussian profiles with the line-of-sight Doppler velocities up to 150 km · s-1 in the N Ⅳ blue/red wings ,which is similar with the explosive events in the transition re-gion .In the past ,explosive events are small-scale dynamic phenomena often observed in the quiet-sun （QS） region ,while their properties in coronal holes （CHs） remain unclear .Here ,we find the EE-like events with strong dynamics in the south solar polar coronal hole by N Ⅳ line of SOHO/SUMER spectrograph .

关 键 词：紫外谱线 冕洞 小尺度结构 

分 类 号：P17[天文地球—天文学]