Photon emission probabilities of 176Lu

An aqueous solution containing dissolved lutetium nitrate with a natural isotopic composition was measured by means of gamma-ray spectrometry to determine emission probabilities of photons which are emitted as a consequence of the decay of the primordial isotope 176Lu. The geometry and matrix of the sample were taken into account in terms of efficiency transfer factors computed with the aid of the upgraded Monte Carlo simulation software GESPECOR. A combination of these results, with the activity determination via liquid scintillation counting using the CIEMAT/NIST efficiency tracing method, yields absolute values of PX(54.61 keV)=0.095(4), PX(55.79 keV)=0.168(5), Pγ(88.36 keV)=0.149(5), Pγ(201.83 keV)=0.777(9) and Pγ(306.84 keV)=0.929(9). In addition, the upper limit of the probability for a potential electron-capture decay of 176Lu was improved using additional high resolution gamma-ray spectra taken with a planar HPGe detector.

► The 176Lu activity of an aqueous lutetium nitrate solution was measured using LSC.
► Absolute photon emission probabilities of the decay of 176Lu were obtained.
► Efficiency transfer factors were computed with the aid of Monte Carlo simulation.
► High resolution gamma-ray spectra of 176Lu were measured.
► The upper limits of the probability for a potential electron-capture decay of 176Lu were improved.