Design of polarized-positron generation system

We have proposed a new method of generating highly polarized positrons through Compton scattering of polarized laser lights o! relativistic electron beams and successive pair creation. To realize high-luminosity laser}electron collisions, we constructed a specially designed chamber which equips o!-axis parabolic mirrors with a through hole at the center. This mirror achieves strong focusing of laser lights as well as head-on collisions of laser lights with e~ beams, so that the luminosity can be signi"cantly increased. A polarimeter is designed for the measurement of positron polarization. ( 2000 Elsevier Science B.V. All rights reserved.