Magnetic Helicity Change Rate Associated with an X10 White-Light Flare

Solar active region NOAA 10486 was very active during the descending phase of solar cycle 23. Eight X-class flares and a multitude of M-class flares were observed in this region from 2003 October 23 to November 6. In our previous study we presented the high resolution observations of the flow fields associated with the X10 white-light flare in this active region on 2003 October 29. We linked the strong photospheric shear flow with the flare. In this paper, we further our study by investigating the magnetic helicity injection rate of the active region NOAA 10486 covering the time period of this X10 white-light flare. The magnetic helicity injection rate due to horizontal photospheric motions is determined by analyzing a set of 1 minute cadence full-disk magnetograms taken by the Michelson Doppler Imager on board the Solar and Heliospheric Observatory, in addition to the flow fields derived previously. The results of this study will aid us to understand the process of energy build-up and release associated with the flare.