Orateur
Description
Despite its success, the Standard Model (SM) is currently being scrutinized on multiple fronts as it fails to explain many features of nature including the matter/anti-matter asymmetry, dark matter and even gravity. One probing mechanism for new physics is the unitarity test of the Cabibbo-Kobayashi-Maskawa matrix. A series of recent transition-independent radiative corrections resulted in a reduction of the Vud matrix element creating a 2.4 sigma tension with unitarity. Consequently, the determination of this matrix element, derived from the ft-value of superallowed beta decays, is under scrutiny. While superallowed pure Fermi transitions currently allow for the most precise determination of Vud, there is currently a growing interest in obtaining that matrix element from superallowed mixed transitions to test the accuracy of Vud and the calculation of isospin symmetry breaking corrections. In the past few years, a research program aimed at solidifying the determination of Vud from mirror transitions was initiated using radioactive ion beams from the Twin Solenoid (TwinSol) separator at the Nuclear Science Laboratory of the University Notre Dame. As part of this program, several half-lives have been measured, some for the first time in 40 years, to relative uncertainties in the 0.01% range. These range from 11C to 33Cl and include the measurement of 20F and, more recently, 28Al, which are also both of interest for searches of second-class currents. These recent measurements as well as future measurements will be presented.
