XCI. The beta spectrum of tritium

Abstract

The beta-spectrum of tritium, H³, has been carefully examined by the proportional counter method down to energies ∼1 KeV. In the present work it has been more thoroughly explored using improved techniques designed to permit accurate measurements of the spectrum shape down to a lower energy limit ∼200 eV. The improvements consisted chiefly in employing a counter which was made “end-free” by means of field-adjusting tubes and the use of an electronic method of measuring the pulse distribution in addition to the moving film technique. The intensity of the spectrum below 1 KeV. was found to be definitely less than theoretically predicted.