Commissioning of the BL3 Proton Trap and Proton Detector Subsystems

The BL3 Collaboration is commissioning a next-generation beam-based neutron lifetime experiment capable of achieving an overall measurement precision of ≤0.3 s. This experimental technique requires the combined absolute measurement of the neutron beam flux through a quasi-Penning trap and the number of beta-decay protons produced within its volume. To achieve the absolute measurement of beta-decay protons, the proton trap must be manufactured to tight tolerances and maintain dimensional stability from its assembly at room temperature to the operational temperature of the superconducting magnet in which it is placed. After one trapping period, protons are released and transported to a multi-segmented silicon detector system designed to measure both incident and backscattered protons with high efficiency. In this talk, the development of these proton trap and proton detector subsystems for the BL3 experiment will be discussed, and the current status of testing and calibration will be presented.