Half-life measurement of 44Sc and 44mSc

Abstract

The half-lives of ⁴⁴Sc and ^44mSc were measured by following their decay rate using several measurement systems: two ionization chambers and three γ-spectrometry detectors with digital and/or analogue electronics. For ⁴⁴Sc, the result was the combination of seven half-life values giving a result of 4.042(7) h, which agrees with the last reported value of 4.042(3) h and confirms the near to 2% deviation from the recommended half-life of 3.97(4) h. Scandium-44 is present as an impurity in the production of ⁴⁴Sc by cyclotron proton irradiation. Its half-life was determined by measurements performed a few days after End of Bomardment (EoB), so that the ⁴⁴Sc decayed down to a negligible level. Seven measurements were combined to obtain an average of 58.7(3) h, which is in agreement with the recommended value of 58.6(1) h.

Keywords: (44)Sc; (44m)Sc; Gamma-spectrometry; Half-life; Ionization chamber; Nuclear data.