A Small-scale Oscillatory Reconnection and the Associated Formation and Disappearance of a Solar Flux Rope

Abstract

We present the observations of a small-scale oscillatory reconnection for the first time and its resulting in formation and disappearance of a flux rope with the high-resolution data obtained by the New Vacuum Solar Telescope and the Solar Dynamics Observatory on 2013 July 24 and 25. This oscillatory reconnection consists of four relatively independent magnetic reconnections which last for about 48, 158, 275, and 340 minutes, respectively. The durations of the four magnetic reconnections increase with time. Four current sheets along two nearly perpendicular directions are formed alternately. The oscillatory reconnection experiences two cycles, and the periods of the two oscillations are 206 and 615 minutes, which are much longer than the previous results. The period of the first oscillation is shorter than that of the second oscillation. Furthermore, a flux rope forms during the second magnetic reconnection. Its twist increases with the reconnection and transfers from the reconnection site to one leg, and this leads the flux rope to become more slender. Then, the flux rope disappears in the early stage of the third magnetic reconnection. We conclude that the formation and disappearance of the flux rope are caused by the oscillatory reconnection.