Transfer of NBS X-ray beam calibrations

Abstract

A large a luminum ion ization chamber has been calibrated atthe United States Nationa Bureau of Standards to d etermin e t he total a mount of energy transpor ted by a bremss trahlung beam. T his chamber was carried to Europe and used to transfer this absolute cali brat ion to simila r io nization chambers in betatron la boratories in France, Western Germ any, Switzerland, and Yugoslavia. The t r ansfers were made by direct experimental co mpa rison o f the chamber sensitivities in t he betatron X-ray beams in t hese laboratories. The t ransferred calibrations were corrected for differences in X-ray beam size and filtration.