Kinetic turbulence in reconnecting current sheets with magnetic islands
Tuesday
Abstract details
id
Kinetic turbulence in reconnecting current sheets with magnetic islands
Date Submitted
2021-04-30 15:47:00
Valentina
Zharkova
Northumbria University
Energetic particles at the Sun and in the heliosphere
Contributed
We investigate the kinetic turbulence generated by accelerated particles in a reconnecting current sheet (RCS) with X- and O-nullpoints and to explore the wavenumber and frequency spectra of kinetic turbulence induced in reconnection region by accelerated particles at the time of quasi-stable acceleration. We carry out simulations of magnetic reconnection in a thin current sheet with 3D magnetic field topology affected by tearing instability until the formation of two large magnetic islands using particle-in-cell (PIC) approach. We show that particles of the same charge accelerated in 3D current sheets form the `bump-on-tail' velocity distributions in different locations of RCS that generates plasma turbulence owing to two beam instabilities. The characteristic waves produced by either electron or proton beams can be identified from the energy spectra of electromagnetic field fluctuations in the phase and frequency domains and compared with the particle energy gains. In a wavenumber space the spectral index of the turbulent magnetic field near the ion inertial length is found to be -2.7 that is consistent with other estimations and measurements. We explore the frequency spectra of high and low-frequency turbulent waves generated in parallel and perpendicular directions to the local magnetic field that shows noticeable lower hybrid turbulence occurring between the electron's gyro- and plasma frequencies.
All attendees are expected to show respect and courtesy to other attendees and staff, and to adhere to the NAM Code of Conduct.