Magnetic elements on the quiet sun are buffeted by convective flows that cause lateral motions on timescales of minutes. The magnetic elements can be observed as bright points (BPs) in the G band at 4305 {\AA}. We present observations of BPs based on a long sequence of G-band images recorded with the Dutch Open Telescope (DOT) and post-processed using speckle masking techniques. From these images we measured the proper motions of isolated BPs and derived the auto-correlation function of their velocity relative to the solar granulation pattern. The accuracy of BP position measurements is estimated to be less than 23 km on the Sun. The rms velocity of BPs (corrected for measurement errors) is about 0.89 km s$^{-1}$, and the correlation time of BP motions is about 60 s. This rms velocity is about 3 times the velocity measured using cork tracking, almost certainly due to the fact that isolated BPs move more rapidly than clusters of BPs. We also searched for evidence of vorticity in the motions of G band BPs.
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机译：对流对静止的太阳上的磁性元素造成冲击，对流导致以分钟为单位的横向运动。可以观察到磁性元素为4305 {\ AA}处G波段中的亮点（BP）。我们基于由荷兰开放式望远镜（DOT）记录并使用斑点掩膜技术进行后处理的G波段图像的长序列提出BP的观察结果。从这些图像中，我们测量了孤立的BP的正确运动，并推导出了它们相对于太阳造粒模式的速度的自相关函数。在太阳上，BP位置测量的精度估计小于23 km。 BP的均方根速度（针对测量误差进行校正）约为0.89 km s $ ^ {-1} $，并且BP运动的相关时间约为60 s。均方根速度约为使用软木塞跟踪测得的速度的3倍，几乎可以肯定是由于孤立的BP比BP簇移动得更快的事实。我们还搜索了G波段BP运动的涡度证据。
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