The electron diffusion region (EDR) is believed to be a key region to the energy conversion associated with magnetic reconnection, from magnetic to kinetic and thermal, but the nature of energy transport and conversion in EDRs is still misunderstood.
In this work, we capitalise on recent studies that have increased the number of referenced EDRs observed by MMS, and perform a statistical study of 71 near X-line events previously identified in the literature. Upon detailed analysis, MMS was found to be located within the inner EDR for 32 of these events, while others correspond to outer EDR or IDR crossings.
We investigate energy partition in their vicinity and find that the electron enthalpy flux dominates within the EDRs compared to the kinetic and heat fluxes. We then evaluate the stationary terms of the energy conservation equation and find that large fluctuations of the electron enthalpy flux divergence tend to occur in the EDRs, showing for a complex energy transfer process dominated by the internal energy flux contribution. Most of the studied EDRs occur at relatively high shear and low guide field conditions, and thus no clear influence of these parameters on the energy conversion rate stands out, though this may also be due to MMS sampling the EDRs at different distances from the X-line. In future work, comparing these results to magnetotail- (symmetric) and magnetosheath- (low shear) EDR will bring insights on how the magnetic reconnection regime can impact the energy conversion and transport.