Εtude de l'interactiοn faible dans la décrοissance de l'32 Αr

Over the past decades, the nuclear β-decay has steadily demonstrated as a reliable instrument to improve our understanding of the weak interaction, extensively permitting to precisely search for the possible existence of physics not originally predicted within the Standard Model (SM) of particle physics. Radioactive nuclei offer indeed unique opportunities to study the structure and the symmetries of the weak interaction, as well as to be competitive with high-energy experiments in the investigation for the possible presence of exotic scalar and tensor interactions not included within the SM firmly established vector – axial-vector (V-A) description of the weak interaction. In this framework, the experimental determination of the "$\tilde{a}_{\beta\nu}$" coefficient - function of both the beta-neutrino angular correlation coefficient (aβν ) and the correlated Fierz term (bF) - for pure both Fermi and Gamow-Teller transitions directly allows to set new limits on the existence of scalar and tensor currents, respectively. A fundamental contribution to improve the present constraints on the scalar and tensor interactions is currently coming from the measurements performed on the kinematic energy shift of the β-delayed protons emitted by 32Ar studied at the WISArD (Weak Interaction Studies with 32Ar Decay) experiment, permanently installed at ISOLDE/CERN. After a successful proof-of-principle experiment and a complete estimation of the associated systematic uncertainties, an upgrade of the existing experimental set-up has been realized through the past two years, potentially permitting to reach the aimed precision of the permil level on the determination of the "$\tilde{a}_{\beta\nu}$" coefficient. In this manuscript, the new experimental campaign conduced at ISOLDE in October 2021 will be presented and the related data analysis, numerical simulations and preliminary results will be discussed.