vix.ing · top · new · best · stats · spec

Kinetic simulations of the Kruskal-Schwarzchild instability in accelerating striped outflows I: Dynamics and energy dissipation

2024/12/12 by William Groger, Groger, William, Hayk Hakobyan +3
Biochemistry, Genetics and Molecular Biology · Engineering · Physics and Astronomy · #FOS: Physical sciences #Fluid Dynamics and Turbulent Flows #Geomagnetism and Paleomagnetism Studies #High Energy Astrophysical Phenomena (astro-ph.HE) #Solar and Space Plasma Dynamics

paper · pdf · doi:10.48550/arxiv.2412.09541

openalex publication_date 2024/12/12 · openalex created_date 2024/12/14 · openalex updated_date 2026/07/28

Abstract

Astrophysical relativistic outflows are launched as Poynting-flux-dominated, yet the mechanism governing efficient magnetic dissipation, which powers the observed emission, is still poorly understood. We study magnetic energy dissipation in relativistic "striped" jets, which host current sheets separating magnetically dominated regions with opposite field polarity. The effective gravity force g in the rest frame of accelerating jets drives the Kruskal-Schwarzschild instability (KSI), a magnetic analogue of the Rayleigh-Taylor instability. By means of 2D and 3D particle-in-cell simulations, we study the linear and non-linear evolution of the KSI. The linear stage is well described by linear stability analysis. The non-linear stages of the KSI generate thin (skin-depth-thick) current layers, with length comparable to the dominant KSI wavelength. There, the relativistic drift-kink mode and the tearing mode drive efficient magnetic dissipation. The dissipation rate can be cast as an increase in the effective width Δ\rm eff of the dissipative region, which follows dΔ\rm eff/dt≃ 0.05 √Δ\rm eff g. Our results have important implications for the location of the dissipation region in gamma-ray burst and AGN jets.

Related