An evaluation of possible mechanisms for anomalous resistivity in the solar corona

Abstract

A wide variety of transient events in the solar corona seem to require explanations that invoke fast reconnection. Theoretical models explaining fast reconnection often rely on enhanced resistivity. We start with data derived from observed reconnection rates in solar flares and seek to reconcile them with the chaos-induced resistivity model of Numata and Yoshida (Phys. Rev. Lett. 88, 045003, 2002) and with resistivity arising out of the kinetic Alfvén wave (KAW) instability. We find that the resistivities arising from either of these mechanisms, when localized over length scales of the order of an ion skin depth, are capable of explaining the observationally mandated Lundquist numbers.