Paper detail

Coherent Lateral Motion of Penumbral Filaments during X-class Flare

The high-resolution pictures of the solar photosphere from space based 50 cm Solar Optical Telescope (SOT) on-board Hinode spacecraft, are now routinely observed. Such images of a delta-sunspot in NOAA 10930 were obtained by Hinode during 13 December 2006 while a X-class flare occurred in this active region. Two bright ribbons were visible even in white light and G-band images apart from chromospheric Ca II H images. We register the sunspot globally using cross-correlation technique and analyse local effects during flare interval. We find that during flare the penumbral filaments show lateral motion. Also, we locate two patches, one in either polarity, which show converging motion towards the polarity inversion line (PIL). In Ca II H images we find kernel with pre-flare brightening which lie along the PIL.