Details of the structure of the weak interaction can be studied either at high-energy collider (energy frontier) or with low-energy beta decay (precision frontier). In high-energy experiment, new particles - mediators of new physics - are searched for. In nuclear beta decay, deviations from an accepted theoretical framework are investigated.
In the talk, I will describe three different approaches using nuclear beta decay to search for beyond standard model physics in the weak sector: (i) super-allowed Fermi 0+ - 0+ decays, (ii) beta-neutrino angular correlation experiments and (iii) beta-shape measurements. The results from these experiments allow to put stringent limits on new contributions to the weak interaction like scalar or tensor terms in addition to the dominant vector and axial-vector currents.