Study of ribbon separation and magnetic reconnection rates

We study the correlation between the speed of two-ribbon separation and the magnetic flux density during the 2001 April 10 solar flare. A weak negative correlation is found between the ribbon separation speed (V_r ) and the longitudinal magnetic flux density (B_z ). In addition, we estimate the magnetic reconnection rate (E_rec ). Along the flare ribbons, E_rec fluctuates in the small range except near the HXR source. The localized enhancement of the reconnection rate corresponds to the position of the HXR source.