Expansion-Driven Self-Magnetization of High-Energy-Density Plasmas

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Lezhnin, K. V., Totorica, S. R., Griff-McMahon, J., Medvedev, M., Landsberger, H., Diallo, A., Fox, W.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913014097117184
author Lezhnin, K. V.
Totorica, S. R.
Griff-McMahon, J.
Medvedev, M.
Landsberger, H.
Diallo, A.
Fox, W.
author_facet Lezhnin, K. V.
Totorica, S. R.
Griff-McMahon, J.
Medvedev, M.
Landsberger, H.
Diallo, A.
Fox, W.
contents Understanding plasma self-magnetization is one of the fundamental challenges in both laboratory and astrophysical plasmas. Self-magnetization can modify the plasma transport properties, altering the dynamical evolution of plasmas. Multiple high-energy-density (HED) experiments have observed the formation of ion-scale magnetic filaments of megagauss strength, though their origin remains debated. Here, we conduct 2D collisional particle-in-cell (PIC) simulations with a laser ray-tracing module for a fully self-consistent simulation of the plasma ablation, expansion, and magnetization. The simulations use a planar geometry, effectively suppressing the Biermann magnetic fields, to focus on anisotropy-driven instabilities. The laser intensity is varied between $10^{13}$ and $10^{14}$ W/$\rm cm^2$, which is relevant to HED and inertial fusion experiments where collisions must be considered. We find that above a critical intensity, the plasma rapidly self-magnetizes via an expansion-driven Weibel process, producing plasma beta of 100 ($β= 8πk_B n_eT_e/B^2$) and Hall parameter $ω_{\rm ce}τ_{e}>1$ within the first few hundred picoseconds. The magnetic field is sufficiently strong to modify plasma heat transport, and simulations with artificially suppressed magnetic field show noticeably different temperature profiles.
format Preprint
id arxiv_https___arxiv_org_abs_2503_15624
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Expansion-Driven Self-Magnetization of High-Energy-Density Plasmas
Lezhnin, K. V.
Totorica, S. R.
Griff-McMahon, J.
Medvedev, M.
Landsberger, H.
Diallo, A.
Fox, W.
Plasma Physics
Understanding plasma self-magnetization is one of the fundamental challenges in both laboratory and astrophysical plasmas. Self-magnetization can modify the plasma transport properties, altering the dynamical evolution of plasmas. Multiple high-energy-density (HED) experiments have observed the formation of ion-scale magnetic filaments of megagauss strength, though their origin remains debated. Here, we conduct 2D collisional particle-in-cell (PIC) simulations with a laser ray-tracing module for a fully self-consistent simulation of the plasma ablation, expansion, and magnetization. The simulations use a planar geometry, effectively suppressing the Biermann magnetic fields, to focus on anisotropy-driven instabilities. The laser intensity is varied between $10^{13}$ and $10^{14}$ W/$\rm cm^2$, which is relevant to HED and inertial fusion experiments where collisions must be considered. We find that above a critical intensity, the plasma rapidly self-magnetizes via an expansion-driven Weibel process, producing plasma beta of 100 ($β= 8πk_B n_eT_e/B^2$) and Hall parameter $ω_{\rm ce}τ_{e}>1$ within the first few hundred picoseconds. The magnetic field is sufficiently strong to modify plasma heat transport, and simulations with artificially suppressed magnetic field show noticeably different temperature profiles.
title Expansion-Driven Self-Magnetization of High-Energy-Density Plasmas
topic Plasma Physics
url https://arxiv.org/abs/2503.15624