POSITRON POLARIZATION IN CHIRAL MEDIA

The positron spin depolarization, relative to the direction of a stati c magnetic field, was investigated in some chiral media where Ps forma tion occurs. The results indicate that helical positrons are able to d istinguish one enantiomer from the other: the remaining polarizations- just before Ps is formed-differ by about 20% on passing from one enant iomer to the other of the same chiral species. Moreover the existence of a process-strictly connected with chirality and able to hinder any depolarizing process more efficiently than the field itself-has been m ade evident at low fields.