Speaker
Description
The Beryllium Electron capture in Superconducting Tunnel junctions (BeEST) experiment searches for the signature of sub-MeV heavy neutrino mass eigenstates in the decay of $^7$Be by precisely measuring the nuclear recoil energy of the $^7$Li daughter nucleus using superconducting tunnel junction (STJ) cryogenic sensors. In Phase-III of the experiment, we utillized a 36-pixel array of the STJ sensors with $^7$Be implantation ranging from 10 to 50 Bq. In this talk, we describe the refined experimental and analytical techniques developed for Phase-III and present the latest results achieved in the Phase-III of the BeEST experiment.
The BeEST experiment is supported, in part, by the DOE-SC Office of Nuclear Physics, the Gordon and Betty Moore Foundation, and the European Metrology Programme for Innovation and Research (EMPIR). TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52- 07NA27344.
