A high-intensity laser-driven positron source

It is widely accepted that the next lepton collider beyond a Higgs factory would require center-of-mass energy of the order of up to 15 TeV. Since, given reasonable space and cost restrictions, conventional accelerator technology reaches its limits near this energy, high-gradient advanced acceleration concepts are attractive. Advanced and novel accelerators (ANAs) are leading candidates due to their ability to produce acceleration gradients on the order of 1–100 GV/m, leading to compact acceleration structures. However, intermediate facilities are required to test the technology and demonstrate key subsystems. A 20-100 GeV center-of-mass energy ANA-based lepton collider can be a possible candidate for an intermediate facility. There is a number of questions that need to be addressed in the course of designing such a facility. One of the most important is the positron beam generation, capture, and acceleration. Here we present a scheme based on an electron beam interaction with a high intensity laser pulse, where a succession of multiphoton Compton and Breit-Wheeler processes leads to the positron beam generation.