Studies of magnetic coupling in the solar atmosphere with observations at Canaries Islands coordinated with satellite observations

2005年7月3日至14日，利用安装在西班牙加那利群岛的太阳望远镜，成功地对太阳表面进行了高空间分辨率的光学观测。参与这次观测的望远镜及其焦面仪器有：1)安装在特内里费岛的德国真空塔望远镜上的两个斯托克斯可见光和红外偏振仪，2)在拉帕尔马的瑞典太阳望远镜的滤光片成像仪，以及3)在拉帕尔马的荷兰开放望远镜的滤光片成像器。这项观测是根据2005年被接受为国际时间方案的观测方案(PI：Y.Katsukawa)进行的。为了监测日冕中的磁场结构和动力学，还利用STRACE和SOHO卫星上的EUV望远镜同时观测到了感兴趣的目标。利用这次观测的数据进行研究，对太阳大气中的动力学和磁耦合有了一些新的认识。我们的发现之一是在太阳黑子护城河区域发生了具有极红移的斯托克斯V信号的小尺度光球事件。斯托克斯V信号的红移表明存在质量下降流，其速度约为10公里/S，超过光球处的音速。活动规模极小，活动持续时间不到1小时。红移信号可以解释为发生在上色球或下光球的磁重联向下流动。

High spatial resolution optical observations of the solar surface was successfully performed using solar telescopes installed on the Canaries Islands, Spain on 3-14 July 2005. The telescopes and their focal plane instruments involved in this observation are : 1) two Stokes polarimeters at visible light and infrared, installed in the German Vacuum Tower Telescope at Tenerife, 2) filter imagers with Swedish Solar Telescope at La Palma, and 3) filter imagers with Dutch Open Telescope at La Palma. This observation was performed based on an observing proposal (PI: Y.Katsukawa) accepted as the International Time Program in 2005. To monitor magnetic-field structure and dynamics in the corona, the target of interest is also observed simultaneously by EUV telescopes onboard TRACE and SoHO satellites.Studies using the data from this observation have given some new knowledge on dynamics and magnetic coupling in the solar atmosphere. One of our finding is small-scale photospheric events with extremely red-shifted Stokes V signal in sunspot moat regions. The red-shift in Stokes V signal suggests the existence of mass downflows with 〜10 km/s, which exceeds a sound velocity at the photosphere. The size of the events is extremely small and the duration of events are less than 1 hour. The red-shifted signal can be interpreted as downward flow from magnetic reconnection occurring at the upper chromosphere or lower photosphere.