Superallowed alpha decays near 100Sn - detector development for measurement of the 104Te lifetime*

An experiment using a YSO implant detector, along with LaBr$_3,$ HAGRiD detectors, is planned to measure the alpha decay chain of $^{108}$Xe to doubly magic, $^{100}$Sn. Previous attempts to measure the half-life of $^{104}$Te resulted in an upper limit of 20ns. The fast scintillation response of the YSO detector will aim for an accurate measurement of the half-lives of both $^{108}$Xe and $^{104}$Te. The result will enable determination of the alpha particle pre-formation factor. Development of the new segmented YSO detector designed for this experiment will be presented.