Measurement of the Polarization of the Frascati 1-GeV Electron Synchrotron<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>γ</mml:mi></mml:math>-Ray Beam From a Diamond Crystal Radiator

Abstract

Results are given from calculations and measurements of the polarization of a 150-Mev photon line in the spectrum of a 1-Bev bremsstrahlung beam obtained with a diamond radiator. Calculations are performed to define the polarization of the entire gamma beam, and the polarization is plotted as a function of the angle between the incident electron momentum and a reciprocal lattice axis. Measurement of the polarization depends upon the fact that in electron pair production from linearly polarized photons the electrons are emitted preferentially in the plane determined by the direction of the incident photon and the polarization vector. The experimental results are tabulated and compared to the theoretical data. (H.D.R.)