Is Flux Submergence an Essential Aspect of Flux Emergence?

High resolution Hinode Spectro-Polarimeter observations permit one to examine the detailed structure of the magnetic field vector in emerging flux regions. We find the field to have a concave-upward geometry on the smallest scales observed (0.3 arcsec), indicating the presence of U-loops at the sites of approaching and canceling opposite polarities. This structure suggests that reconnection is taking place at or below the surface, allowing the emerging flux to rid itself of its considerable mass burden. Supersonic down flows are often observed adjacent to, but not coincident with, the sites of canceling flux. We propose that these are the sites that drain the mass contained in the buoyantly-rising flux elements. The observations then suggest a process of sub-surface reconnection producing O-loops that then are forced to descend with the intergranular convective down flows, thus making flux submergence important to the larger scale flux emergence process.