End and Wall Corrections for Absolute Beta-Counting in Gas Counters

Abstract

A37 (2.8 kev Auger electrons) and Kr85 (0.74 Mev β) were used to determine end corrections for gas counters with flat ends and brass walls. The corrections were found to agree with those published previously for C14 (0.154 Mev). Argon-alcohol fillings were used with small quantities of the active gas being studied. Wall loss corrections were measured for Kr85 and calculated for A37, C14, and Kr85. It appears from the results that absolute beta-counting for energies from about 0.01 to 0.8 Mev to an accuracy of one or two percent can be accomplished by the use of flat end Geiger counters applying the corrections indicated.