Uniformity of Beta-ray Plane Sources for the Calibration of Surface Contamination Monitors.

Uniformity of different types of beta-ray plane sources has been examined. Four types of plane sources, polymer, anodized aluminum, filter and ion exchange membrane, were selected. On estimation of the uniformity, the coefficient of variation with respect to surface emission rate was measured using an imaging plate or a proportional counter. As a result, polymer sources and ion exchange membrane sources showed good uniformity. The area and number of region of interest for estimation of uniformity were discussed.