A method of polarization analysis of electrons from optically pumped He_
McCusker, Michael Vance
Walters, G. King
Master of Arts
An experiment in progress to extract a polarized beam of electrons from an optically pumped helium source gas is described. Possible ionization mechanisms in helium gas are outlined and the methods of optical pumping are shown to provide a method for identifying electrons arising from those mechanisms involving the 23s1 metastable state. Calculations show that assuming conservation of spin, electrons extracted from the source gas should have an appreciable polarization. Apparatus for extraction of the electrons and for their acceleration to 120 KeV is described. The procedure for a Mott scattering analysis of the polarization of the electron beam is explained and a scattering chamber which has been constructed for this purpose is described and shown to be adequate for these measurements.