Angle-dependent pair production in the polarized two-photon Breit-Wheeler process

The advent of laser-driven high-intensity gamma-photon beams has opened up new opportunities for designing advanced photon-photon colliders. Such colliders have the potential to produce a large yield of linear Breit -Wheeler (LBW) pairs in a single shot, which offers a unique platform for studying the polarized LBW process. In our recent work [Q. Zhao et al., Signatures of linear Breit-Wheeler pair production in polarized gamma gamma collisions, Phys. Rev. D 105, L071902 (2022)], we investigated the polarization characteristics of LBW pair production in circularly-polarized (CP) gamma-photon collisions. To fully clarify the polarization effects involving both CP and linearly-polarized gamma-photons, here we further investigate the LBW process using the polarized cross section with explicit azimuthal-angle dependence due to the base rotation of photon -polarization vectors. We accomplished this by defining a new spin basis for positrons and electrons, which enables us to decouple the transverse and longitudinal spin components of e +/-. By means of analytical calculations and Monte Carlo simulations, we find that the linear polarization of photon can induce the highly angle-dependent pair yield and polarization distributions. The comprehensive knowledge of the polarized LBW process will also open up avenues for investigating the higher-order photon-photon scattering, the laser-driven quantum electrodynamic plasmas and the high-energy astrophysics.