Half-life of tritium and the Gamow-Teller transition rate

The half-life of tritium implanted into a Si(Li) x-ray detector has been determined to be 12.32\ifmmode\pm\else\textpm\fi{}0.03 yr by following the decay for about 5.5 years. Using a recently determined \ensuremath{\beta}-decay end-point energy for the same system, the product (${G}_{A}$/${G}_{V}$)〈\ensuremath{\sigma}\ensuremath{\tau}〉 for tritium has been determined to be 2.094\ifmmode\pm\else\textpm\fi{}0.004.