title: Brownian motion under annihilation dynamics.
abstract: The behavior of a heavy tagged intruder immersed in a bath of particles evolving under ballistic annihilation dynamics is investigated. The Fokker-Planck equation for this system is derived and the peculiarities of the corresponding diffusive behavior are worked out. In the long time limit, the intruder velocity distribution function approaches a Gaussian form, but with a different temperature from its bath counterpart. As a consequence of the continuous decay of particles in the bath, the mean-squared displacement increases exponentially in the collision per particle time scale. Analytical results are finally successfully tested against Monte Carlo numerical simulations.
authors.affiliation: Université Paris-Sud, LPTMS, UMR 8626, Orsay Cedex, F-91405 and CNRS, Orsay, F-91405, France.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: García de Soria
authors.forename: Pablo
authors.initials: P
authors.lastname: Maynar
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Trizac