The Relativistic Maxwell-Jüttner Velocity Distribution Function

Abstract: In this paper, the expression of the relativistic Maxwell-J\"uttner velocity distribution was deduced in a detailed and didactic way. This distribution was compared with the well-known Maxwell-Boltzmann distribution, which does not take into account relativistic effects. Applications and comparisons between the two distributions were carried out in three situations: i) protons at solar surface temperature, ii) electrons at Lawson's criterion temperature, and iii) protons at quasar temperatures. It was found that the value of the ratio between the rest mass of the particle considered and the temperature of the system determines the need to consider or not a relativistic treatment for the velocity distribution function of the system.