We report on the first compelling observation of α decay of 151Eu to the ground state of 147Pm. The measurement was performed using a 6.15 g Li6Eu(BO3)3 crystal operated as a scintillating bolometer. The Q-value and half-life measured are: Q = 1948.9±6.9(stat.)±5.1(syst.) keV, and T1/2=(4.62±0.95(stat.)±0.68(syst.))×1018 y . The half-life prediction of nuclear theory using the Coulomb and proximity potential model are in good agreement with this experimental result.
@article{arxiv.1311.2834,
title = {Discovery of the $^{151}$Eu $\alpha$ decay},
author = {N. Casali and S. S. Nagorny and F. Orio and L. Pattavina and J. W. Beeman and F. Bellini and L. Cardani and I. Dafinei and S. Di Domizio and M. L. Di Vacri and L. Gironi and M. B. Kosmyna and B. P. Nazarenko and S. Nisi and G. Pessina and G. Piperno and S. Pirro and C. Rusconi and A. N. Shekhovtsov and C. Tomei and M. Vignati},
journal= {arXiv preprint arXiv:1311.2834},
year = {2014}
}