No abstract

The WISArD experiment is probing the possible existence of exotic currents in the electroweak sector using nuclear decay, to improve the constraints on beyond Standard Model physics. The setup of the experiment underwent a full upgrade between 2018 and 2021 in preparation of a second run of data taking at ISOLDE, CERN, scheduled for October 2021. The detector stage was completely renewed to improve statistics and minimize the main systematic effects identified in a proof-of-principle run in 2018. With this upgrade, the objective is to reach the per-mil level of uncertainty on the angular correlation coefficent and on the Fierz interference term , in a pure Fermi transition. In this case, both parameters are directly sensitive to the possible contribution of exotic scalar currents.