Stationary distribution functions for Tokamak-plasmas in the weak-collisional transport regime by MaxEnt principle

TL;DR

This paper demonstrates that stationary distribution functions for tokamak plasmas in the weak-collisional regime can be derived solely using the MaxEnt principle with scale-invariant restrictions, linking them to entropy production.

Contribution

It shows that the stationary distribution functions for tokamak plasmas can be obtained from the MaxEnt principle alone, without additional assumptions, and relates them to entropy production.

Findings

Stationary distribution functions can be derived from MaxEnt with scale invariance.

The distribution functions relate to the Prigogine distribution and entropy production.

Potential extension to neoclassical distribution functions in collisional regimes.

Abstract

In previous works, we derived stationary density distribution functions (DDF) where the local equilibrium is determined by imposing the maximum entropy (MaxEnt) principle, under the scale invariance restrictions, and the minimum entropy production theorem. In this paper we demonstrate that it is possible to reobtain these DDF solely from the MaxEnt principle subject to suitable scale invariant restrictions in all the variables. For the sake of concreteness, we analyze the example of ohmic, fully ionized, tokamak-plasmas, in the weak-collisional transport regime. In this case we show that it is possible to reinterpret the stationary distribution function in terms of the Prigogine distribution function where the logarithm of the DDF is directly linked to the entropy production of the plasma. This leads to the suggestive idea that also the stationary neoclassical distribution functions, for magnetically confined plasmas in the collisional transport regimes, may be derived solely by the MaxEnt principle.