Quasi-periodic outflows observed by the X-Ray Telescope onboard Hinode in the boundary of an active region  

作　　者：Li-Jia Guo Hui Tian Jian-Sen He 

机构地区：[1]School of Earth and Space Sciences, Peking University, Beijing 100871, China guolijia32 @ 163. com [2]Max-Planck-Institut fur Sonnensystemforschung, 37191 Katlenburg-Lindau, Germany

出　　处：《Research in Astronomy and Astrophysics》2010年第12期1307-1314,共8页天文和天体物理学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.40874090 and 40931055)

摘　　要：Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.

关 键 词：solar wind -- Sun： UV radiation -- active region 

分 类 号：P112[天文地球—天文学] TP301.6[自动化与计算机技术—计算机系统结构]