A new investigation of half-lives for the decay modes of \(^{50}\)V

A new search for the decay modes of the 4-fold forbidden non-unique decay of \(^{50}\)V has been performed at the Gran Sasso Underground Laboratory (LNGS). In total an exposure of 197 kg \(\times\) d has been accumulated. The half-life for the electron capture into the first excited state of \(^{50}\)Ti has been measured with the highest precision to date as \(2.67_{-0.18}^{+0.16} \times 10^{17}\) yr (68% C.I.) in which systematics uncertainties dominate. The search for the \(\beta\)-decay into the first excited state of \(^{50}\)Cr resulted in a lower limit of \({1.9} \times 10^{19}\) yr (90% C.I.), which is an improvement of almost one order of magnitude compared to existing results. The sensitivity of the new measurement is now in the region of theoretical predictions.