Si Detector Timing Studies for the Nab Experiment

Precision measurements of kinematic correlation parameters of free neutron decayserve as a powerful probe of the Standard Model of particle physics. A wide array of Beyond the Standard Model physics theories can be probed by precision neutron physics. The Nab experiment will measure a, the electron-neutrino correlation coefficient, and b, the Fierz interference term. a is amongst the most sensitive decay parameters to λ = gA/gV , the ratio of the axial-vector and vector coupling constants in the weak force. Two important systematic considerations for the Nab experiment are average detector timing bias, which must be held to ≤ 0.3 ns, and energy calibration and linearity, which must be held to 1 part in 104 . Both systematics require an in depth understanding of charge collection in Nab’s Si detectors. Simulation of Si charge collection using numerical methods and the Shockley-Ramo Theorem has been completed. A variety of detector tests, including detector and amplification electronics acceptance testing have also been completed. Also included in this dissertation is my work with the Nab ultra-high vacuum and cryogenic system.