Turbulence in Magnetic Reconnection Jets from Injection to Sub-Ion Scales

Phys Rev Lett. 2024 Mar 8;132(10):105201. doi: 10.1103/PhysRevLett.132.105201.

Abstract

We investigate turbulence in magnetic reconnection jets in the Earth's magnetotail using data from the Magnetospheric Multiscale spacecraft. We show that signatures of a limited inertial range are observed in many reconnection jets. The observed turbulence develops on the timescale of a few ion gyroperiods, resulting in intermittent multifractal energy cascade from the characteristic scale of the jet down to the ion scales. We show that at sub-ion scales, the fluctuations are close to monofractal and predominantly kinetic Alfvén waves. The observed energy transfer rate across the inertial range is ∼10^{8} J kg^{-1} s^{-1}, which is the largest reported for space plasmas so far.