Generation of polarized positron beams via collisions of ultrarelativistic electron beams

A novel scheme is proposed for generating a polarized positron beam via multiphoton Breit-Wheeler process during the collision of 10 GeV, pC seeding electron with other 1 nC driving beam. The provides strong self-generated field, and suitable transverse deviation distance between two beams enables field experienced by to be unipolar, which crucial realizing polarization. We employ particle simulation Monte-Carlo method calculate spin- polarization-resolved photon emission electron-positron pair production in local constant approximation. Our results show that highly polarization above $40\%$ can generated several femtoseconds, robust respect parameters beams. Based on an analysis influence $\gamma$-photon production, we find proper initial further improve $60\%$.