Ca II Transient Brightenings Associated with Canceling Magnetic Features

Abstract

We analyzed transient Ca II H brightening associated with small-scale canceling magnetic features (CMFs) in the quiet Sun near disk center using Ca II H filter images and Na D₁ magnetograms of Hinode/SOT. We found that in most Ca II brightening events related to CMFs the Ca II H intensity peaks after the magnetic flux cancellation. Moreover, the brightening tends to appear as a pair of bright points of similar size and brightness overlying a magnetic bipole. Then a new opposite polarity fragment moves to them and cancels out. These results imply that magnetic reconnection takes place there and is responsible for CMFs.