[séminaire] Searching for new physics in the beta-decay of laser trapped He-6

by Arnaud Leredde

Tuesday 30 Jan 2018, 11:00 → 12:00 Europe/Paris

Grand Amphi (LPSC)

Despite the success of the Standard Model (SM) of particle physics at describing subatomic particles and their interaction, its limitations are well known. Among them are the dominance of matter over anti-matter in the Universe, the neutrino oscillations implying their non-zero mass, the absence of candidate for dark matter and its incompatibility with gravity. Driven by predictions from extensions of the SM or new theories, searches are being conducted in several ways to answer those questions. Precision experiments, searching for new interactions as a source of nuclear decays, is one of them. The $^6$He experiment at the University of Washington (Seattle) is searching for tensor-like contributions to the $\beta$-decay of laser trapped $^6$He by measuring precisely the $\beta - \nu$ angular correlation parameter, $a_{\beta \nu}$. The precision and statistics required for a 1$\%$ measurement of $a_{\beta \nu}$ has been reached and the systematic effects are currently being studied in details. During the presentation, I will give a general overview of the effort to improve the constrains on scalar and tensor contributions (presently excluded from the SM), and a detailed description of the $^6$He experiment and its current status.