Identifying and Capturing of Magnetopause Reconnection Diffusion Region and Initial MMS Observations

Abstract:

The primary objective of the MMS mission is to explore and understand the fundamental plasma physics of magnetic reconnection, with emphasis on kinetic plasma processes in the diffusion region that are responsible for collisionless reconnection. This objective is challenging experimentally because (1) highly accurate particle and field measurements must be made at extremely high sampling rates by four spacecraft and (2) the reconnection diffusion region is seldom encountered by spacecraft because of its minuscule scale size: the widths of the ion and electron diffusion regions, which scale as the ion and electron inertial lengths, are of the order of 50 km and 1 km, respectively, at the magnetopause. We will discuss the MMS strategies for identifying and transmitted data from diffusion region encounters. We will also show initial MMS observations of reconnection at the magnetopause.