The Broken Lane of a Type II Radio Burst Caused by Collision of a Coronal Shock with a Flare Current Sheet

摘要

We investigated a peculiar metric type II solar radio burst with a brokenlane structure, which was observed on November 13, 2012. In addition to theradio data, we also studied the data in the other wavelengths. The bursts wereassociated with two CMEs and two flares that originated from active region AR11613. A long current sheet was developed in the first CME, and the second CMEcollided with the current sheet first and then merged with the first one.Combing information revealed by the multi-wavelength data indicated that acoronal shock accounting for the type II radio burst, and that the collision ofthis shock with the current sheet resulted in the broken lane of the type IIradio burst. The type II burst lane resumed after the shock passed through thecurrent sheet. We further estimated the thickness of the current sheetaccording to the gap on the lane of the type II burst, and found that theresult is consistent with previous ones obtained for various events observed indifferent wavelengths by different instruments. In addition, the regular typeII burst associated with the first CME/flare was also studied, and the magneticfield in each source region of the two type II bursts was further deduced indifferent way.