A probability assessment of encountering dayside magnetopause diffusion regions

Probability maps for encountering the reconnection electron diffusion region of the dayside magnetopause have been developed using a model of reconnection and solar wind observations. The maps indicate that along the magnetopause surface, the chance of directly sampling the diffusion region during a given season varies considerably. The probability distribution depends strongly on the distribution of interplanetary magnetic field directions and, also, is significantly influenced by the Earth's intrinsic magnetic dipole field tilt angle. The probability also scales with the assumed size of the diffusion region. The probability distribution shows little dependence on the phase of the solar cycle.