Impact parameter dependence of dilepton production: Wigner function approach and the role of photon polarizations

Abstract

We revisit the Wigner function approach to the impact parameter dependent dilepton pair production developed in [M. Klusek-Gawenda, WS, A. Szczurek Phys. Lett. B 814 (2021) 136114]. We study the distribution of the angle between difference and sum of lepton transverse momenta, and show how it relates to the orbital angular momentum of leptons. The dependence on impact paramter is discussed, and we also present  the different components of the Wigner function in the t-channel. A brief comparison to similar angular distributions in diffractive quark pair production will be presented.