Efficient Particle Acceleration in 2.5-dimensional Hybrid-kinetic Simulations of Decaying Supersonic Plasma Turbulence

Keyan Gootkin; Colby Haggerty; Damiano Caprioli; Zachary Davis

doi:10.3847/1538-4357/ae5d42

Back

Efficient Particle Acceleration in 2.5-dimensional Hybrid-kinetic Simulations of Decaying Supersonic Plasma Turbulence

Journal article

Open access

Peer reviewed

Efficient Particle Acceleration in 2.5-dimensional Hybrid-kinetic Simulations of Decaying Supersonic Plasma Turbulence

Keyan Gootkin, Colby Haggerty, Damiano Caprioli and Zachary Davis

The Astrophysical journal, Vol.1003(2), p.212

06/01/2026

DOI: 10.3847/1538-4357/ae5d42

Files and links (1)

url

https://doi.org/10.3847/1538-4357/ae5d42View

Published (Version of record) Open Access

Abstract

Collisionless, turbulent plasmas surround the Earth, from the magnetosphere to the intergalactic medium, and the fluctuations within them affect nearly every field in the space sciences, from space weather forecasts to theories of galaxy formation. Where turbulent motions become supersonic, their interactions can lead to the formation of shocks, which are known to efficiently energize ions to cosmic-ray energies. We present 2.5-dimensional hybrid-kinetic simulations of decaying, supersonic, nonrelativistic turbulence in a collisionless plasma using the code dHybridR. The ions are initially cold ( beta i similar or equal to 116 ), although they heat rapidly at the onset of turbulence. Turbulence within these simulations is highly compressible; after accounting for this compression by taking the omnidirectional power spectrum of the density-weighted velocity field, we find turbulent spectra with power-law slopes of alpha approximate to-53 for low Mach numbers, in the inertial range, and alpha approximate to -2 for high Mach numbers. Ions embedded in the highly supersonic simulations are accelerated to high energies at efficiencies similar to those seen in shocks, despite being in a nonrelativistic regime and lacking the large-scale structure of a shock. We observe that particles are accelerated into a power-law spectrum, with a slope of q approximate to 2.5 in (nonrelativistic) energy. We compare these results to those obtained from the theory and simulations of diffusive shock acceleration and discuss the astrophysical implications of this theoretical work.

Physical Sciences

Astronomy & Astrophysics

Science & Technology

Details

Title: Subtitle: Efficient Particle Acceleration in 2.5-dimensional Hybrid-kinetic Simulations of Decaying Supersonic Plasma Turbulence
Creators: Keyan Gootkin - University of Hawaii System
Colby Haggerty - University of Hawaii System
Damiano Caprioli - University of Chicago
Zachary Davis - University of Hawaii System
Resource Type: Journal article
Publication Details: The Astrophysical journal, Vol.1003(2), p.212
DOI: 10.3847/1538-4357/ae5d42
ISSN: 0004-637X
eISSN: 1538-4357
Publisher: IOP Publishing Ltd
Number of pages: 18
Grant note: HTMS-80NSSC24K0173 / National Aeronautics and Space Administration (NASA); National Aeronautics & Space Administration (NASA) PHY-2205991 / National Science Foundation (NSF)
Language: English
Date published: 06/01/2026
Academic Unit: Physics and Astronomy
Record Identifier: 9985224317902771

Metrics

1 Record Views