A study of asymmetric reconnection scaling in the Lyon-Fedder-Mobarry code

Using a three-dimensional magnetospheric simulation code we have studied the properties of magnetic reconnection at the subsolar point on solar wind parameters for southward interplanetary magnetic field conditions and compared the results with the predictions of the Cassak-Shay theory. We find that this theory predicts reconnection rates on the order of our observations and produces reasonable predictions of the reconnection outflow speed. We have quantified the contributions that differences between the assumed and measured mass, energy, and outflow density scalings make to predictions of the reconnection rate and outflow speed. In general, the theory makes reasonable assumptions about the mass and energy flux into the reconnection layer, but their outflowing counterparts are overestimated due to the narrowness of the reconnection outflow jet. Lastly, we find that newly reconnected flux tubes exit the merging region before their mass density can equilibrate, requiring a correction to the predicted outflow density.