Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429

We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class （X5.4 and X1.3） flares using data from the Helioseismic and Magnetic Imager on board the SolarDynamics Observatory. A large leading sunspot with positive magnetic polarity rotated counterclock-wise. As expected, the rotation was significantly affected by the two flares. Magnetic transients inducedby the flares were clearly evident in the sunspots with negative polarity. They were moving across thesunspots with speed of order 3 - 7 km s^-1. Furthermore, the trend of magnetic flux evolution in thesesunspots exhibited changes associated with the flares. These results may shed light on understanding theevolution of sunspots.