Year: 2026
Type: article
Abstract: The mechanism for accelerating energetic particles in the outer heliosphere is still under debate. The termination shock, turbulence, and magnetic reconnection have all been proposed as viable mechanisms. We investigate compression-driven particle acceleration during magnetic reconnection in the heliospheric current sheet using the MHD–SDE framework that incorporates energetic particle feedback into the MHD evolution. For the heliosheath conditions considered here, we find that reconnection-driven acceleration is inefficient downstream of the termination shock, whereas reconnection near the heliopause can generate stronger compression and produce a power-law differential intensity spectrum J ( ε ) ∝ ε −5.4 . However, even the hardest spectrum achieved during magnetic reconnection remains much steeper than the typical J ( ε ) ∝ ε −1.5 spectrum observed in the heliosheath. This indicates that magnetic reconnection alone is insufficient to explain the acceleration of energetic particles in the heliosheath.
Source: The Astrophysical Journal
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, National Energy Research Scientific Computing Center, Office of Science, National Nuclear Security Administration, Smithsonian Astrophysical Observatory, Laboratory Directed Research and Development, Los Alamos National Laboratory
Awards: G1017065088, G1279347439, G1527848044, G1766003928, G2356915424, G2495227331, Collaborative Research: The Role of Supra-arcade Downflows on Energy Transfer in Solar Flares, Collaborative Research: The Role of Supra-arcade Downflows on Energy Transfer in Solar Flares, G5395596559, G564812881, G6410514744, G6563880843, G6871336836, G70659677, Collaborative Research: Achieving a New Understanding of Solar Flare Termination Shocks
OpenAlex ID: W7225290582