Classical ultrarelativistic bremsstrahlung in higher dimensions

Abstract

We consider the classical bremsstrahlung of an ultrarelativistic point-like particle on potential, generated by the free infinite Nambu-Goto object ([Formula: see text]-brane). For simplicity, the interaction is supposed to take place via the bulk scalar field. Scalar interaction can model both the vector field and the trace part of linearized gravity. The particle does not intersect the Nambu-Goto object and moves in transverse directions, thus in the ultrarelativistic limit we can regard its trajectory as straight and make use of the perturbation theory. We derive the radiation amplitudes and compute the emitted energy during the collision. The validity of classical consideration is discussed. The results are analyzed in the context of co-dimensionality of the brane embedding.