Energetic Particle Acceleration in Compressible Magnetohydrodynamic Turbulence
نویسندگان
چکیده
Magnetohydrodynamic (MHD) turbulence is an important agent of energetic particle acceleration. Focusing on the compressible properties magnetic turbulence, we adopt test method to study acceleration from Alfv\'en, slow and fast modes in four regimes that may appear a realistic astrophysical environment. Our studies show (1) second-order Fermi mechanism drives particles cascade processes three by particle-turbulence interactions, regardless whether shock wave appears; (2) not only can power spectra maximum rates reveal inertial range but also recover scaling energy ratio relationship between modes; (3) mode dominates particles, especially case super-Alfv\'enic supersonic for sub-Alfv\'enic very high range, Alfv\'en significant at early stage acceleration; (4) results power-law distribution certain evolution time. From perspective particle-wave interaction, this paper promotes understanding both behavior acceleration, which will help insight into involved MHD turbulence.
منابع مشابه
Acceleration of energetic particles by large-scale compressible magnetohydrodynamic turbulence
Fast particles diffusing along magnetic field lines in a turbulent plasma can diffuse through and then return to the same eddy many times before the eddy is randomized in the turbulent flow. This leads to an enhancement of particle acceleration by largescale compressible turbulence relative to previous estimates in which isotropic particle diffusion is assumed.
متن کاملAcceleration of particles in imbalanced magnetohydrodynamic turbulence.
The present work investigates the acceleration of test particles, relevant to the solar-wind problem, in balanced and imbalanced magnetohydrodynamic turbulence (terms referring here to turbulent states possessing zero and nonzero cross helicity, respectively). These turbulent states, obtained numerically by prescribing the injection rates for the ideal invariants, are evolved dynamically with t...
متن کاملCosmic Ray Scattering by Compressible Magnetohydrodynamic Turbulence
Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for substantial revisions in the picture of cosmic ray transport. In this paper we use recently obtained scaling laws for MHD modes to calculate the scattering frequency for cosmic rays in the ISM. We consider gyroresonance with MHD modes (Alfvénic, slow and fast) and transit-time damping (TTD) by fast modes. We provi...
متن کاملNumerical Study of Compressible Magnetohydrodynamic Turbulence in Two Dimensions
We have studied forced turbulence of compressible magnetohydrodynamic (MHD) flows through two-dimensional simulations with different numerical resolutions. First, hydrodynamic turbulence with Mach number 〈Ms〉init ≡ 〈v〉rms/cs = 1 and density compression 〈δρ/ρ〉rms ≃ 0.45 was generated by enforcing a random force. Then, initial, uniform magnetic fields of various strengths were added with Alfvénic...
متن کاملCosmic-ray Scattering and Streaming in Compressible Magnetohydrodynamic Turbulence
Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of cosmic-ray transport. In this paper we use recently obtained scaling laws for MHD modes to obtain the scattering frequency for cosmic rays. Using quasi-linear theory, we calculate gyroresonance with MHD modes (Alfvénic, slow, and fast) and transit-time damping (TTD) by fast modes. We pr...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2021
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/1538-4357/ac28ff