A measurement of the photon emission probabilities for the 161-, 303- and 384-keV γ-rays in the decay of 133Xe

Abstract

The relative emission probabilities for the 161-, 303- and 384-keV γ-rays emitted during the decay of 133Xe have been measured by comparing spectra obtained from a sample with spectra from standard 133Ba sources. Corrections were made for random losses, differences in geometry, attenuation due to differing source encapsulation and coincident summing effects. From the corrected rates, the emission probabilities relative to the sum of the 80- and 81-keV γ-rays are 24.2±2.5 × 10 −4, 1.93±0.07 × 10 −4 and 0.90±0.04 × 10 −4 for the 161-, 303- and 384-keV γ-rays respectively. If the sum of the 80- and 81-keV γ-ray emission probabilities is 0.383±0.007, the emission probabilities of the 161-, 303- and 384-keV γ-rays are 9.3±1.0 × 10 −5 and 3.5±0.2 × 10 −5 respectively. All uncertainties quoted here and in the following paper are one standard deviation equivalent unless otherwise stated.