2021/12/31 by I. Y. Vasko, Ivan Y. Vasko, K. Alimov +9
Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Atomic physics #Classical mechanics #Computational physics #Condensed matter physics #Current (fluid) #Current density #Current sheet #Geometry #Ionosphere and magnetosphere dynamics #Kinetic energy #Lambda #Length scale #Magnetic field #Magnetohydrodynamics #Mechanics #Nuclear physics #Optics #Physics #Proton #Quantum mechanics #Solar and Space Plasma Dynamics #Solar wind #Thermodynamics #physics.plasm-ph #physics.space-ph
paper · pdf · doi:10.3847/2041-8213/ac4fc4
7 pages + list of references, 5 figures
arxiv created 2021/12/31 · openalex publication_date 2022/02/01 · arxiv updated 2022/03/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present analysis of 17,043 proton kinetic-scale current sheets collected over 124 days of Wind spacecraft measurements in the solar wind at 11 Samples/s magnetic field resolution. The current sheets have thickness λ from a few tens to one thousand kilometers with typical value around 100 km or from about 0.1 to 10λp in terms of local proton inertial length λp. We found that the current density is larger for smaller scale current sheets, J0≈ 6 \rm nA/m2 ⋅ (λ/100 \rm km)-0.56 , but does not statistically exceed critical value JA corresponding to the drift between ions and electrons of local Alvén speed. The observed trend holds in normalized units, J0/JA≈ 0.17⋅ (λ/λp)-0.51. The current sheets are statistically force-free with magnetic shear angle correlated with current sheet spatial scale, Δθ≈ 19∘⋅ (λ/λp)0.5. The observed correlations are consistent with local turbulence being the source of proton kinetic-scale current sheets in the solar wind, while mechanisms limiting the current density remain to be understood.