Magnetic Reconnection in Plasmas

In situ study of reconnection and associated electron heating in thin current sheets

13 Aug 2015, 12:00

25m

FD5 (Nordita, Stockholm)

Oral Workshop, August 10-14 Pre-noon IV

Speaker

Alexandros Chasapis (Laboratoire des Physiques des Plasmas)

Description

We present an in situ study of thin current sheets and associated electron heating in turbulent space plasma. We use Cluster observations made in the turbulent plasma downstream of the Earth's quasi-parallel shock and we analyze the properties of ion-scale current sheets. Intermittent structures were identified using the Partial Variance of Increments method. We studied the distribution of the identified structures as a function of their magnetic shear angle, the PVI index and the electron heating. We observed a distinct population of high PVI (<3) structures that accounted for ~20% of the total. Enhancement of the estimated electron temperature within these current sheets suggest that they are important for local electron heating and energy dissipation. Evidence of ongoing reconnection was found in a subset of this population. In those cases, multi-spacecraft observations allow to study electron distributions and wave activity at different locations around the x-line. We discuss the possible mechanisms of electron heating and acceleration and the role of thin current sheets for dissipation in turbulent reconnection.