PROPOSED METHOD TO PRODUCE A HIGHLY POLARIZED E(+) BEAM FOR FUTURE LINEAR COLLIDERS

We propose a method to produce a spin-polarized ef beam using e(+)e(-) pair-creation by circularly polarized photons. Assuming Compton scatt ering of an unpolarized e(-) beam and circularly polarized laser light , scattered gamma-rays at the high end of the energy spectrum are also circularly polarized. If those gamma-rays are utilized to create e(+/ -) pairs on a thin target, the spin-polarization is preserved for e(+) 's at the high end of their energy spectrum. By using the injector lin ac of Accelerator Test Facility at KEK and a commercially available Nd :YAG pulse laser, we can expect about 10(5) polarized e(+)'s per secon d with a degree of polarization of 80% and a kinetic energy of 35-80 M eV. The apparatus for creation and measurement of polarized e(+)'s is being constructed. We present new idea for possible application of our method to future Linear colliders by utilizing a high-power CO2 laser .