Reaction operator approach to multiple elastic scatterings

We apply the Gyulassy-Levai-Vitev reaction operator formalism to compute the effects of multiple elastic scatterings of on-shell partons propagating through dense matter. We derive the elastic reaction operator and demonstrate that the recursion relations have a closed form solution that reduces to the familiar Glauber form. We also investigate the accuracy of the Gaussian dipole approximation for the parton transverse momentum broadening.