慢磁声波在黑子上方冕环中的传播  

Propagation of the Slow Magnetoacoustic Waves in Coronal Loops above the Sunspot

作　　者：李海东[1] 赵丽[1] 梁红飞[1] 毕以[2] 洪俊超[2] 郑瑞生[2] 

机构地区：[1]云南师范大学物理与电子信息学院,昆明650500 [2]中国科学院云南天文台,昆明650011

出　　处：《天文学报》2013年第1期27-38,共12页Acta Astronomica Sinica

基　　金：国家自然科学基金项目(10878014;11063005);云南省自然科学基金项目(2009CD046;2007A194M)资助

摘　　要：太阳动力学观测站(Solar Dynamics Observatory,SDO)装载的太阳大气成像系统(Atmospheric Imaging Assembly,AIA)通过3个极紫外波段(171 A、193 A和211(?))的观测资料展现了太阳活动区(AR 11092)扇形冕环微弱的扰动传播,这种波动现象普遍存在于活动区冕环.该扰动传播起源于明亮的环足处,其传播沿冕环方向.冕环中观测到的扰动传播速度随温度升高而减小,速度范围是40～121 km/s,其值接近且小于声速.考虑投影效应以及环与视线方向的倾角大小,这正好是慢波模型所预期的.冕环的扰动周期在不同波段(3个极紫外波段)没有明显的区别,都存在3 min以及10多分钟的周期.此外,不仅仅冕环扰动表现出3 min左右的周期,色球层的黑子区域同样存在相同的振荡周期.这个结果表明黑子振荡是可以穿过色球以及过渡区到达日冕的.The observations from the Atmospheric Imaging Assembly （AIA） onboard the Solar Dynamics Observatory （SD0） reveal the weak propagating disturbances （PDs） in the fan-like coronal loops of the active region （AR 11092） in 171 A, 193 A, and 211 A. These PDs seem to be a common phenomenon in this part of the active region. The disturbances originate from small-scale brightenings at the footpoints of the loops and propagate along the loops. The observed propagation speeds decreased when the PDs were propagating in hotter plasmas. It roughly varies between 40 km/s and 121 km/s for three bandpasses, which is close to and below the expected sound speed in the coronal loops. Considering the pro- jection effect and different angles to our line of sight, it is exactly what the slow-wave model expects. The wavelet analysis does not show a significant difference among the periods of the PDs observed in different bandpasses. The periodic patterns of two distinct periods, 3 min and more than 10 min, are detected in three bandpasses. Not only the coronal loops but also the sunspot regions on the chromosphere display intensity oscillations with a period of the order of 3 min. This result suggests that the sunspot oscillations can propagate into the corona through the chromospheres and the transition region.

关 键 词：太阳 日冕 太阳 振荡 太阳 紫外辐射 太阳 过渡区 波 

分 类 号：P182[天文地球—天文学]