Measurements in nuclear beta decay provide the most precise information available on the unitarity of the CKM matrix, a key test for the possible existence of physics beyond the Standard Model.
Extremely pure isotopic samples are produced from the MARS recoil spectrometer (in the case of 22Mg the beam was >99.9% pure). The fast tape-transport system is then used to move the collected samples to a shielded counting position where beta-decay half-lives and gamma-ray intensities are measured with uniquely high precision.
