Electron Temperature Enhancement Events in the Terrestrial Magnetosheath: A Statistical Study

Abstract Sudden enhancements of electron temperature over a short time periods, referred to as electron temperature enhancement events (ETEEs), are frequently observed in the terrestrial magnetosheath. This study utilizes high‐resolution data provided by the Magnetospheric Multiscale (MMS) mission from September 2015 to May 2018 to conduct a statistical analysis of ETEEs in the Earth's magnetosheath. We identified a total of 1509 ETEEs, among which 451 were observed in magnetic holes, 265 in current sheets, 104 in magnetic peaks, and 40 in flux ropes, with 649 ETEEs corresponding to unidentified magnetic structures. Our statistical results show that the ETEEs are mainly concentrated on the flanks of the magnetosheath, especially near the magnetopause and the bow shock region where the occurrence rates are highest. The average duration of ETEEs is 1.52 s, and the average spatial scale is 4.07 ion gyroradius, and 480.3 electron gyroradius, implying that ETEEs belong to ion‐scale structures. Furthermore, the average ratio of electron parallel temperature to perpendicular temperature in ETEEs is 1.17, indicating that the electron parallel temperature may have a greater impact on the overall electron temperature increase in ETEEs. Our results shed new light on the electron dynamics in the terrestrial magnetosheath.