Nonextensivity in the Solar Neighborhood

TL;DR

This study analyzes the velocity distribution of low-mass stars in the solar neighborhood, revealing that their distributions follow q-Gaussians from nonextensive statistics, indicating hierarchical phase space structures.

Contribution

It demonstrates that stellar velocity distributions are better described by nonextensive statistics, introducing a novel application of q-Gaussians to astrophysical stellar data.

Findings

Velocity distributions fit q-Gaussians better than standard Gaussians.

Results suggest hierarchical phase space structure in stellar dynamics.

Supports nonextensive statistical mechanics in astrophysics.

Abstract

In the present study, we analyze the radial velocity distribution as a function of different stellar parameters such as stellar age, mass, rotational velocity and distance to the Sun for a sample of 6781 single low--mass field dwarf stars, located in the solar neighborhood. We show that the radial velocity distributions are best fitted by $q$--Gaussians that arise within the Tsallis nonextensive statistics. The obtained distributions cannot be described by the standard Gaussian that emerges within Boltzmann-Gibbs (B--G) statistical mechanics. The results point to the existence of a hierarchical structure in phase space, in contrast to the uniformly occupied phase space of B--G statistical mechanics, driven by the $q$--Central Limit Theorem, consistent with nonextensive statistical mechanics.