A laser–plasma platform for photon–photon physics: the two photon Breit–Wheeler process

We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes such as the linear Breit-Wheeler process with real photons. The has been developed using Gemini laser facility at Rutherford Appleton Laboratory. A wakefield accelerator and bremsstrahlung convertor are used generate collimated beam of photons energies hundreds MeV, that collide keV x-ray generated by heated plasma target. To detect pairs collisions, magnetic transport system which directs onto scintillation-based hybrid silicon pixel single particle detectors. present commissioning results from an experimental campaign this physics, demonstrating successful generation both photon sources, characterisation calibration detectors, discuss feasibility observation process. design will also serve basis investigation strong-field nonlinear Trident process, or eventually, scattering.