Scaling of reconnection rate toward "electron-only" magnetic reconnection

Magnetospheric Multiscale (MMS) Mission observation indicates that “electron-only” reconnection is pervasive in Earth’s magnetosheath [Phan et al., 2019]. In light of this observation and following work, such a novel type of reconnection is now expected to play a significant role in dissipating magnetic energy within plasma turbulence. Among other properties, it is critical to determine how rapid reconnection processes the magnetic flux therein as it determines the energy conversion rate from magnetic fields to particles. Previous numerical simulations suggest that the normalized reconnection rate can exceed the typical value of 0.1, reaching the order of unity. While it was suggested that this higher rate is due to super-Alfvenic electron jets, a complete theory does not yet exist. In this talk, we report our progress in modeling the transition from the standard ion-coupled reconnection rate to this electron-only reconnection rate, which can be of great interest to the broad community that studies turbulence, shocks, and laboratory laser-driven reconnection.