Upgrade of the SPIRAL identification station for high-precision measurements of nuclear β decay
Abstract The low-energy identification station at SPIRAL (Systeme de Production d'Ions Radioactifs Acceleres en Ligne) has been upgraded for studying the β decays of short-lived radioactive isotopes and to perform high-precision half-life and branching-ratio measurements for superallowed Fermi and isospin T= 1 / 2 mirror β decays. These new capabilities, combined with an existing Paul trap setup for measurements of β–ν angular-correlation coefficients, provide a powerful facility for investigating fundamental properties of the electroweak interaction through nuclear β decays. A detailed description of the design study, construction, and first results obtained from an in-beam commissioning experiment on the β+ decays 14 O and 17F are presented.