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Previously, using an incompressible von Kármán–Howarth formalism, the behavior of cross-scale energy transfer in magnetic reconnection and turbulence was found to be essentially identical to each other, independent of an external magnetic (guide) field, in the inertial and energy-containing ranges [Adhikari et al., Phys. Plasmas 30, 082904 (2023)]. However, this description did not account for the energy transfer in the dissipation range for kinetic plasmas. In this Letter, we adopt a scale-filtering approach to investigate this previously unaccounted-for energy transfer channel in reconnection. Using kinetic particle-in-cell simulations of antiparallel and component reconnection, we show that the pressure–strain interaction becomes important at scales smaller than the ion inertial length, where the nonlinear energy transfer term drops off. Also, the presence of a guide field makes a significant difference in the morphology of the scale-filtered energy transfer. These results are consistent with kinetic turbulence simulations, suggesting that the pressure strain interaction is the dominant energy transfer channel between electron scales and ion scales.
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This content will become publicly available on November 1, 2026
Energy transfer and conversion in magnetic reconnection: Observation and simulation
One of the central problems in collisionless plasma turbulence is to understand the nature of the cross-scale energy transfer and dissipation occurring at kinetic scales. Magnetic reconnection plays an important role in dissipating energy and driving energy transfer in these systems. However, for reconnection, a detailed picture of the fluxes of energy in its several forms, and the conversion among them, until now remains unclear. In this study, a scale filtering method is adopted to explore how energy is converted between different forms and transferred across scales in turbulent magnetic reconnection using a combination of Magnetospheric Multiscale observations and particle-in-cell simulations. Two novel findings of this paper are that both ion and electron dissipation start to occur at sub-ion scale, at nearly same scale, and that most of the energy cascade due to reconnection is carried by the electron fluid.
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- PAR ID:
- 10688037
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Physics of Plasmas
- Volume:
- 32
- Issue:
- 11
- ISSN:
- 1070-664X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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