Twist propagation in Hα surges

We have studied Mees Solar Observatory Halpha spectroheliogram and Doppler velocity movies of surges in 11 active regions. We used these movies to observe the surges' rotating motion, direction of propagation, and the implied handedness of that motion. We were able to coregister movies containing 47 surges with Haleakala Stokes Polarimeter vector magnetograms. We could hence determine the direction of twist stored in the magnetic field at the point of origin of each surge. We found (with a 99% confidence) that the direction of observed spin of these surges is consistent with the relaxation of the stored twist in the magnetic field. Magnetic reconnection of twisted flux tubes with their less twisted surroundings can account for the production and rotating motion of these surges.