Nuclear Physics Seminar: Mr. Louis Varriano, University of Chicago


Location: 184 Nieuwland Science Hall

Search for an electroweak tensor contribution using trapped 8Li with the Beta-decay Paul Trap Mk IV

Mr. Louis Varriano
University of Chicago

The Beta-decay Paul Trap (BPT) measures the beta-neutrino angular correlation coefficient aβν in the Gamow-Teller decays of 8Li and 8B (decaying to 8Be*→2α) to search for a tensor component of the weak interaction, a beyond-Standard Model possibility. The new BPT Mk IV trap reduces β-scattering by a factor of 4, a key source of systematic uncertainty, and has recently been commissioned with 8Li with 2.7 million triple coincidence events. In addition, a complete detector characterization has been performed with an α beam to reduce systematic uncertainties associated with the silicon strip detector response. This new high-statistics 8Li data set, coupled with the experimental advancements, will allow for improved sensitivity to a tensor contribution. In the near future, the BPT should be able to reach an uncertainty of |CT /CA|2 ≤ 10−3, though the theoretical understanding of the nuclear structure still requires improvement.

Hosted by Prof. Brodeur