UCNB Experimental Overview: Recent Progress and Future Goals

The UCNB experiment is an effort to measure the neutrino-asymmetry $B$, between the neutrino momentum and the neutron spin in polarized neutron beta-decay. Bottled ultracold neutrons are held in a magnetic field until they decay, and a 30 kV accelerating potential allows both the electrons and protons to be detected by thin dead layer pixellated silicon detectors. Proton-electron coincidences have been directly observed, and a second detector has been implemented. Continued improvements are planned, including better data acquisition, improved electrostatic configuration, and improvements to the decay trap to prevent neutron loss and escape.