Kinetic Equilibrium of Dipolarization Fronts

Abstract

The unprecedented high-resolution data from the Magnetospheric Multi-Scale (MMS) satellites is revealing the physics of dipolarization fronts created in the aftermath of magnetic reconnection in extraordinary detail. The data shows that the fronts contain structures on small spatial scales beyond the scope of fluid framework. A new kinetic analysis, applied to MMS data here, predicts that global plasma compression produces a unique particle distribution in a narrow boundary layer with separation of electron and ion scale physics. Layer widths on the order of an ion gyro-diameter lead to an ambipolar potential across the magnetic field resulting in strongly sheared flows. Gradients along the magnetic field lines create a potential difference, which can accelerate ions and electrons into beams. These small-scale kinetic effects determine the plasma dynamics in dipolarization fronts, including the origin of the distinctive broadband emissions.

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Document Details

Document Type
Technical Report
Publication Date
Nov 21, 2018
Accession Number
AD1101031

Entities

People

  • Alex C. Fletcher
  • Chris Crabtree
  • David Malaspina
  • Erik Tejero
  • G. Ganguli
  • Ian Cohen

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Artificial Satellites
  • Boundary Layer
  • Broadband
  • Distribution Functions
  • Electric Fields
  • Electron Density
  • Electrons
  • Energy
  • Environment
  • Equations
  • Free Energy
  • Frequency
  • Magnetic Fields
  • Measurement
  • Pressure Gradients
  • Simulations
  • Spacecraft

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Plasma Physics / Magnetohydrodynamics

Technology Areas

  • Microelectronics
  • Space
  • Space - Hall-Effect Thruster