Determination of the cosmic antideuteron flux in a Monte Carlo approach

We investigate in this paper the antideuteron flux produced in high energy collisions of cosmic rays with interstellar matter. We employ a modified version of the Monte Carlo generator DPMJET-III together with the coalescence model to simulate, in an event-by-event basis, the antideuteron production in cosmic ray collisions in our Galaxy. Then, we use a diffusion model to calculate the expected flux. We find a secondary antideuteron flux at the Earth with a central value which is a factor of 2 smaller than in previous calculations, although still affected by large uncertainties due to the antideuteron production and propagation.