X-RAY BRIGHT POINT FLARES DUE TO MAGNETIC RECONNECTION

Ground-based optical observations coordinated with Yohkoh/SXT X-ray ob servations of an old, disintegrating bipolar active region AR NOAA 749 3 (May 1, 1993) provided a multiwavelength data base to study a flarin g 'active region' X-ray bright point (XBP) of about 16 hr lifetime, an d the activity related to it in different layers of the solar atmosphe re. The XBP appeared to be related to a new minor bipole of about 10(2 0) Mr. Superposed on a global evolution of soft X-ray brightness, the XBP displayed changes of brightness, lasting for 1-10 min. During the brightenings the XBP apparently had a spatial structure, which was (ti ny) loop-like rather than point-like. The X-ray brightenings were corr elated with chromospheric activity: (i) brightenings of underlying chr omospheric faculae, and (ii) appearance of strong turbulent velocities in the arch filament system. We propose that the XBP brightenings wer e due to reconnection of the magnetic field lines (sketched in 3D) bet ween the new bipole and a pre-existing plage field induced by the moti on of one of the new pores (nu = 0.2 km s(-1)) towards the plage, and that the XBP itself was a reconnected hot loop between them.