Mj. Woods et Sem. Lucas, HALF-LIFE OF SR-90 - MEASUREMENT AND CRITICAL-REVIEW, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 369(2-3), 1996, pp. 534-538
Recent evaluations of the half-life of Sr-90 have demonstrated the var
iable quality of the available experimental data which has prevented t
he estimation and adoption of a value that commands confidence. In an
attempt to reduce the uncertainty in the half-life to an acceptable le
vel, the decay of a Sr-90 source has been followed for over six years
at NPL. The equipment comprised matching, re-entrant, high-pressure io
nization chambers and a long-lived reference source to reduce non-rand
om effects. The experimental technique is described together with the
statistical procedure used to analyse the measured data. A half-life v
alue was determined together with an estimate of the associated uncert
ainties. A new evaluation of the Sr-90 half-life has been made, taking
account of the new NPL data and other recent measurements. Particular
attention has been paid to the experimental techniques used to produc
e the data and the uncertainties attributed to them. An objective eval
uation has been conducted to produce a new recommended half-life value
of 10516 +/- 21 days.