A New Measurement of the Neutron Beta-Neutrino Correlation with the aCORN Experiment

by Prof. Fred E. Wietfeldt (Department of Physics and Engineering Physics, Tulane University)

Monday 15 Nov 2021, 14:30 → 15:30 Europe/Berlin

Zoom Webinar

The decay of the free neutron into a proton, electron, and antineutrino is the simplest beta decay system. The beta electron-antineutrino angular correlation (a-coefficient) is one of several important experimental parameters of neutron decay. Together these can be used to measure the weak decay couplings G_A and G_V, determine important fundamental parameters of the weak nuclear force, and conduct precision low energy tests of physics beyond the Standard Model. The aCORN experiment uses a novel “wishbone asymmetry” method that, unlike previous experiments, does not require detailed proton spectroscopy. aCORN ran at the NIST Center for Neutron Research in 2013-2014 and then at the new high flux end position NG-C in 2015-2016. The combined result, published in 2021, has an overall uncertainty of 1.7%. Details of the experiment and analysis will be presented.