Using a two-dimensional, three-component magnetohydrodynamic model, anumerical study is presented on the disturbance of prominence caused byphotospheric magnetic cancellation. Photospheric magneticcancellation below the prominence transports magnetic flux into theprominence, resulting in an increase of both magnetic flux andhelicity in the prominence. The state of the prominence is related toits accumulated magnetic flux (or magnetic helicity). As shown in thenumerical results, when F (the relative increment of magnetic flux inthe prominence) or H(the corresponding relative increment of magnetichelicity) is small, the prominence rises and expands only slightly,and remains in contact with the photosphere. On the other hand, whenF or His large, the prominence is detached from the photosphere andeventually is suspended in the lower corona, leading to the formation ofa vertical current sheet below the prominence.%采用二维三分量理想磁流体力学模型, 研究光球磁对消引起的日珥扰动. 日珥下方光球表面的磁对消将磁通量向日珥传输, 引起日珥内部磁通量和磁螺度增加. 日珥的状态与所积累的磁通量(或磁螺度)有关. 数值结果显示, 如果日珥磁通的相对增量F (或相应的磁螺度相对增量H)较小, 日珥只略微上升和膨胀, 并不离开光球; 而对于较大的F (或H), 日珥将脱离光球, 悬浮在低层日冕中, 在其下方形成垂直电流片.
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