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  • Machine Learning Characterization of Intermittency in Relativistic Pair Plasma Turbulence: Single and Double Sheet Structures

This content will become publicly available on May 22, 2026

Title: Machine Learning Characterization of Intermittency in Relativistic Pair Plasma Turbulence: Single and Double Sheet Structures
Abstract The physics of turbulence in magnetized plasmas remains an unresolved problem. The most poorly understood aspect is intermittency—spatiotemporal fluctuations superimposed on the self-similar turbulent motions. We employ a novel machine learning analysis technique to segment turbulent flow structures into distinct clusters based on statistical similarities across multiple physical features. We apply this technique to kinetic simulations of decaying (freely evolving) and driven (forced) turbulence in a strongly magnetized pair-plasma environment, and find that the previously identified intermittent fluctuations consist of two distinct clusters: (i) current sheets, thin slabs of electric current between merging flux ropes, and; (ii) double sheets, pairs of oppositely polarized current slabs, possibly generated by two nonlinearly interacting Alfvén-wave packets. The distinction is crucial for the construction of realistic turbulence subgrid models.  more » « less
Award ID(s):
2409223
PAR ID:
10598323
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ApJL
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
985
Issue:
2
ISSN:
2041-8205
Page Range / eLocation ID:
L31
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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