title: Fokker-Planck-Kramers equation for a Brownian gas in a magnetic field.
abstract: In this work we give an alternative method to calculate the transition probability densities (TPD) for the velocity space, phase space, and Smoluchowsky configuration space of a Brownian gas of charged particles in the presence of a constant magnetic field. Our proposal consists in transforming, by means of a rotation matrix, the Langevin equation of a charged particle in the velocity space into another velocity space where the behavior is quite similar to that of ordinary Brownian motion. A similar strategy is also applied to the phase-space. In consequence, in the transformed space both the Fokker-Planck and Fokker-Planck-Kramers equations are solved following Chandrasekhar's methodology. Our results are compared with those obtained by Czopnik and Garbaczewski [Phys. Rev. E 63, 021105 (2001)].
authors.affiliation: Departamento de Física, Universidad Autónoma Metropolitana, Iztapalapa, Apartado Postal 55-534, C.P. 09340, Mexico, D.F., Mexico. ines@xanum.uam.mx
authors.forename: J I
authors.initials: JI
authors.lastname: Jiménez-Aquino
authors.forename: M
authors.initials: M
authors.lastname: Romero-Bastida