Positron–electron scattering and Bhabha exchange effects

The study of positron–electron scattering is made using a Wilson cloud chamber to check the presence of Bhabha exchange effects. The observed scattering cross section is more than the value calculated from Moller's theory of positron–electron scattering, where only the Coulomb interaction between the particles is considered. However, the experimental results are in good agreement with the theory if the exchange effects suggested by Bhabha are also included.