FIVE-DIMENSIONAL QED, MUON PAIR PRODUCTION AND CORRECTION TO THE COULOMB POTENTIAL

Abstract

We consider QED in five dimensions in a configuration where matter is localized on a 3-brane while foton propagates in the bulk. The idea is to investigate the effects of the Kaluza–Klein modes of the photon in the relativistic regime, but in low energy, and in the nonrelativistic regime. In the relativistic regime, we calculate the cross-section for the reaction e++e-→μ++μ-. We compare our theoretical result with a precise measurement of this cross-section at [Formula: see text]. As result, we extract a lower bound on the size of the extra dimension. In the nonrelativistic regime, we derive the contribution for the Coulomb potential due to the whole tower of the Kaluza–Klein excited modes of the photon. We use the modified potential to calculate the Rutherford scattering differential cross-section.