2025/09/09 by Abiam Tamburrini, Tamburrini, Abiam, Sergio Davis +3
Physics and Astronomy · #Dust and Plasma Wave Phenomena #FOS: Physical sciences #Ionosphere and magnetosphere dynamics #Plasma Physics (physics.plasm-ph) #Statistical Mechanics and Entropy
paper · pdf · doi:10.48550/arxiv.2509.07927
openalex publication_date 2025/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
From the perspective of non-equilibrium statistical mechanics, modeling the velocity distribution of particles in non-equilibrium, steady-state plasmas presents a significant challenge. Under this context, a family of kappa distributions has been widely used to capture the high-energy tails in space plasmas. These distributions deviate from the canonical Maxwell-Boltzmann statistics and vary significantly in their interpretation of the temperature of an out-of-equilibrium system. In this letter, we establish the validity of any kappa distribution from the standpoint of superstatistics. This study unifies these models by introducing a new kappa distribution based on superstatistical parameters, providing a more general and fundamental framework to connect these distributions and the superstatistical temperature of a system. We demonstrate that the general distribution depends on the thermal characteristics of the modeled temperature distribution population. Furthermore, we present a moment-based velocity distribution that bypasses the traditional temperature debate, relying on the velocity moments. Our findings enhance the understanding of kappa distributions and offer a robust model for non-equilibrium space plasmas.