Gamma-Induced Electron Emission from Conducting Surfaces

The current from the surfaces of metals exposed in vacuum to ⁶⁰Co gamma radiation was measured to determine the electron emission. The metals were in the form of solid cylinders 1.27-cm (0.50-in.) diam × 10.2 cm (4.0 in.) long. The electron emission factors increased smoothly with atomic number Z, varying from (3.06 ± 0.63) × 10^-17 A/cm² per rad/h (absorbed dose) for carbon to (18.2 ± 0.4) × 10^-17 A/cm² per rad/h (absorbed dose) for lead.