Acceleration of Particles in Imbalanced Magnetohydrodynamic Turbulence

Abstract

The present work investigates the acceleration of test particles in balanced and imbalanced Alfvénic turbulence, relevant to the solar-wind problem. These turbulent states, obtained numerically by prescribing the injection rates for the ideal invariants, are evolved dynamically with the particles. While the energy spectrum for balanced and imbalanced states is known, the impact made on particle heating is a matter of debate, with different considerations giving different results. By performing direct numerical simulations, resonant and non-resonant particle accelerations are automatically considered and the correct turbulent phases are taken into account. For imbalanced turbulence, it is found that the acceleration rate of charged particles is reduced and the heating rate diminished. This behaviour is independent of the particle gyroradius, although particles that have a stronger adiabatic motion (smaller gyroradius) tend to experience a larger heating.

arXiv comment5 pages 6 figures

References in corpus (14)

• Spectrum of magnetohydrodynamic turbulence
• Measurement of the electric fluctuation spectrum of magnetohydrodynamic turbulence
• Universality of solar wind turbulent spectrum from MHD to electron scales
• A Model of Turbulence in Magnetized Plasmas: Implications for the Dissipation Range in the Solar Wind
• Perpendicular Ion Heating by Low-Frequency Alfven-Wave Turbulence in the Solar Wind
• Gyrokinetic Simulations of Solar Wind Turbulence from Ion to Electron Scales
• Role of cross helicity in magnetohydrodynamic turbulence
• Rapid directional alignment of velocity and magnetic field in magnetohydrodynamic turbulence
• Anisotropy of Imbalanced Alfvenic Turbulence in Fast Solar Wind
• Stochastic Acceleration in Turbulent Electric Fields Generated by 3-D Reconnection
• Numerical study of Cosmic Ray Diffusion in MHD turbulence
• Test-particle acceleration in a hierarchical three-dimensional turbulence model
• The Turbulent Heating Rate in Strong MHD Turbulence with Nonzero Cross Helicity
• Controlling the level of the ideal invariant fluxes for MHD turbulence using TURBO spectral solver

Cited by in corpus (9)

• Acceleration and Escape Processes of High-energy Particles in Turbulence inside Hot Accretion Flows
• Stochastic Particle Acceleration in Turbulence Generated by the Magnetorotational Instability
• Cosmic-ray pitch-angle scattering in imbalanced MHD turbulence simulations
• Test particle energization and the anisotropic effects of dynamical MHD turbulence
• On the compressibility effect in test particle acceleration by magnetohydrodynamic turbulence
• Compressible helical turbulence: Fastened-structure geometry and statistics
• Test particle energization of heavy ions in magnetohydrodynamic turbulence
• A Unified Phenomenology of Ion Heating in Low-$\beta$ Plasmas: Test-Particle Simulations
• Effect of the electronic pressure on the energy and magnetic moment of charged test particles in turbulent electromagnetic fields