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DOE OSTI · 1840007

Half-life of 67 Cu

Merrick, Michael J.·Rotsch, David A.·Tiwari, Ashok·Nolen, Jerry·Brossard, Thomas·Song, Jeongseog·Wadas, Thaddeus J.·Sunderland, John J.·Graves, Stephen A.
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Abstract

The half-life of 67 Cu was determined through serial gamma-ray spectrometry measurements of the dominant gamma emission (E γ : 184.6 keV; branching ratio: 48.7%) produced following β- decay. Data were collected consecutively for 1000 s per measurement, with a total of 3063 measurements over the duration of 36 days. The incidence rate for the 184.6 keV gamma-ray was determined from the spectral peak area and duration of each measurement. This rate was then corrected to account for detector dead-time, radioactive decay during each acquisition and drift in the computer clock in comparison to NIST nuclear clock. Least-squares regression analysis was performed to determine the half-life of 67 Cu. The result was 61.761 ± 0.004 h, which is the highest precision measurement to date, and marks a 24-fold precision improvement over the current Nuclear Data Sheets value.

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Merrick, Michael J., Rotsch, David A., Tiwari, Ashok, Nolen, Jerry, Brossard, Thomas, Song, Jeongseog, Wadas, Thaddeus J., Sunderland, John J., Graves, Stephen A.. 2021-08-13. Half-life of 67 Cu. https://doi.org/10.1088/2399-6528%2Fac1ad8

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