2024/08/13 by Uddipan Banik, A. Bhattacharjee, Banik, Uddipan +3 · 2 citations
Engineering · Physics and Astronomy · #Astrophysics of Galaxies (astro-ph.GA) #Electrohydrodynamics and Fluid Dynamics #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Laser-induced spectroscopy and plasma #Plasma Physics (physics.plasm-ph) #Solar and Stellar Astrophysics (astro-ph.SR) #Space Physics (physics.space-ph) #Statistical Mechanics (cond-mat.stat-mech) #Vacuum and Plasma Arcs
paper · pdf · doi:10.48550/arxiv.2408.07127
openalex publication_date 2024/08/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Distribution functions of collisionless systems are known to show non-thermal power law tails. Interestingly, collisionless plasmas in various physical scenarios, (e.g., the ion population of the solar wind) feature a v-5 tail in the velocity (v) distribution, whose origin has been a long-standing mystery. We show this power law tail to be a natural outcome of the self-consistent collisionless relaxation of driven electrostatic plasmas. We perform a quasilinear analysis of the perturbed Vlasov-Poisson equations to show that the coarse-grained mean distribution function (DF), f0, follows a quasilinear diffusion equation with a diffusion coefficient D(v) that depends on v through the plasma dielectric constant. If the plasma is isotropically forced on scales much larger than the Debye length with a white noise-like electric field, then D(v)∼ v4 for σ