Nonextensivity in nonequilibrium plasma systems with Coulombian long-range interactions

The nonextensivity in a non-isothermal plasma system with the Coulombian long-range interactions is studied in the framework of Tsallis statistics. We present for first time a mathematical expression of the nonextensive parameter q based on the mathematical theory about the generalized Boltzmann equation and the q-H theorem and the Maxwellian q-velocity distribution. We obtain a new physical explanation for q concerning the nature of non-isothermal configurations in plasma systems with Coulombian long-range interactions. We also provide one illustration for Almeida theorem (Physica A 300(2001)424) from the kinetic analyses of plasma systems, which means that Tsallis statistics might be a suitable statistics for the description of a nonequilibrium system with a temperature gradient in it.