The nonextensive parameter for nonequilibrium electron gas in an electromagnetic field

• An expression of the qq-parameter is obtained for nonequilibrium plasma with electromagnetic interactions.
• The qq-parameter is related to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the plasma.
• The qq-parameter represents the nonequilibrium nature of the complex plasma with electromagnetic interactions.

The nonextensive parameter for nonequilibrium electron gas of the plasma in an electromagnetic field is studied. We exactly obtained an expression of the qq-parameter based on Boltzmann kinetic theories for plasmas, where Coulombian interactions and Lorentz forces play dominant roles. We show that the qq-parameter different from unity is related by an equation to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the gas. The effect of the magnetic field on the qq-parameter depends on the overall bulk velocity. Thus the qq-parameter for the electron gas in an electromagnetic field represents the nonequilibrium nature or nonisothermal configurations of the plasma with electromagnetic interactions.