Electron Polarization
Abstract
The double scattering experiment has been repeated with a 400-kev beam of electrons obtained from a Van de Graaff electrostatic generator. The electrons are scattered by thin gold foils and are counted by Geiger-Müller counters. After eliminating spurious asymmetries, a polarization asymmetry of 8 percent for gold foils is found, which becomes 1 percent in the opposite direction when an aluminum foil is inserted in place of one of the gold foils. Reducing the atomic number of the scattering centers in this way should reduce the theoretical polarization asymmetry to a much smaller value. The reflection-transmission effect found by Chase and Cox has been confirmed and is shown to play an important part in polarization experiments. A reflection polarization experiment (in which only electrons which have been "reflected" from the inclined foils are studied) is shown to produce a much smaller asymmetry than does a transmission polarization experiment (in which only electrons which have been transmitted through the inclined foils are studied). A final polarization ratio of 1.12+/-0.02 is obtained for comparison with the theory.
- Publication:
-
Physical Review
- Pub Date:
- January 1943
- DOI:
- 10.1103/PhysRev.63.29
- Bibcode:
- 1943PhRv...63...29S