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This thesis chronicles measurements of ultracold neutrons (UCN) performed at TRIUMF in fall 2018 and fall 2019. Heat response data of the UCN source bottle was taken by measuring its temperature using the vapour pressure of the 4He. The time-dependence of the He-II bottle temperature is well-described by a model where heat transport is limited by quantum turbulence in the He-II. In addition, measurements of UCN spin manipulation components showed that the adiabatic fast-passage device had a spin flipping efficiency of 0.977 ± 0.008 and 1.007 ± 0.008, and the spin analyzers had a measured polarizing power of 0.650 ± 0.003 and 0.630 ± 0.003. Simulations show that the low spin analyzer efficiency is most likely due to a lower than expected magnetization in the foils, and additional sources of depolarization around the spin-analyzers. The simulations of the analyzer show that the single pass polarizing power of the foil is 0.78 ± 0.08. Under the assumption of no transmission of the wrong spin state through the superconducting magnet, the polarizing power was measured as 0.57 ± 0.05. Simulations reveal that the bore was responsible for some reduction in polarizing power, however better magnetic field gradient control for the spin flipper gradient is required to rule out the possibility of inefficient spin flippers as the cause of the depolarization.

This thesis chronicles measurements of ultracold neutrons (UCN) performed at TRIUMF in fall 2018 and fall 2019. Heat response data of the UCN source bottle was taken by measuring its temperature using the vapour pressure of the 4He. The time-dependence of the He-II bottle temperature is well-described by a model where heat transport is limited by quantum turbulence in the He-II. In addition, measurements of UCN spin manipulation components showed that the adiabatic fast-passage device had a spin flipping efficiency of 0.977 ± 0.008 and 1.007 ± 0.008, and the spin analyzers had a measured polarizing power of 0.650 ± 0.003 and 0.630 ± 0.003. Simulations show that the low spin analyzer efficiency is most likely due to a lower than expected magnetization in the foils, and additional sources of depolarization around the spin-analyzers. The simulations of the analyzer show that the single pass polarizing power of the foil is 0.78 ± 0.08. Under the assumption of no transmission of the wrong spin state through the superconducting magnet, the polarizing power was measured as 0.57 ± 0.05. Simulations reveal that the bore was responsible for some reduction in polarizing power, however better magnetic field gradient control for the spin flipper gradient is required to rule out the possibility of inefficient spin flippers as the cause of the depolarization.

A non-zero neutron electric dipole moment (nEDM) would indicate time-reversal and charge-parity violation. Our collaboration is developing an experiment at TRIUMF to improve the sensitivity to the nEDM by one order of magnitude ($10^{-27}$~e$\cdot$cm). I developed a highly sensitive magnetometer based on nonlinear magneto-optical rotation (NMOR) in Rb vapour. In the future such magnetometers will serve in an array to form an auxiliary magnetometer system monitoring the stability and uniformity of the magnetic field in the nEDM experiment. The operation of the magnetometer in a free-induction-decay mode was the focus of this thesis. The precision of the field measurement, drifts over time, the impact of degaussing, and measurements of transverse fields were studied using the magnetometer.

A non-zero neutron electric dipole moment (nEDM) would indicate time-reversal and charge-parity violation. Our collaboration is developing an experiment at TRIUMF to improve the sensitivity to the nEDM by one order of magnitude ($10^{-27}$~e$\cdot$cm). I developed a highly sensitive magnetometer based on nonlinear magneto-optical rotation (NMOR) in Rb vapour. In the future such magnetometers will serve in an array to form an auxiliary magnetometer system monitoring the stability and uniformity of the magnetic field in the nEDM experiment. The operation of the magnetometer in a free-induction-decay mode was the focus of this thesis. The precision of the field measurement, drifts over time, the impact of degaussing, and measurements of transverse fields were studied using the magnetometer.

Next generation electric dipole moment experiments require precise knowledge of the local magnetic fields in the experimental volume. Hyperpolarized xenon-129 has been proposed as a comagnetometer gas to be used in the neutron electric dipole moment experiment planned for TRIUMF. A flow through xenon polarizer was constructed and tested, and the hyperpolarized Xe-129 produced was transported to and characterized using a new AFP-NMR spectrometer. The polarization measured in the external AFP-NMR spectrometer was (12 ± 4)%. The longitudinal spin relaxation time T1 was found to be (77 ± 24) s in the experimental NMR volume, limited by leaks and field inhomogeneity. This represents good progress towards the eventual system for nEDM experiments where polarizations greater than 50% and T1, T2 relaxation times greater than 1000 s are expected.

Future fundamental physics experiments in neutron beta-decay require highly efficient detection of protons. Many of the experiments use electrostatic acceleration of the recoil protons into large-area silicon detectors for this purpose. A 30~keV proton accelerator was designed, created, and commissioned in order to characterize silicon detectors of this type. Final construction and initial results on the performance of the accelerator are presented. A unique aspect of the work is the use of a Penning ion generator as an ion source. The accelerator produced protons with momentum resolution ~1%. The ion source produced current stably, over a range of parameters, and over long periods of time. The accelerator achieved proton rates sufficient to calibrate silicon detectors.

Next generation electric dipole moment experiments require precise knowledge of the local magnetic fields in the experimental volume. Hyperpolarized xenon-129 has been proposed as a comagnetometer gas to be used in the neutron electric dipole moment experiment planned for TRIUMF. A flow through xenon polarizer was constructed and tested, and the hyperpolarized Xe-129 produced was transported to and characterized using a new AFP-NMR spectrometer. The polarization measured in the external AFP-NMR spectrometer was (12 ± 4)%. The longitudinal spin relaxation time T1 was found to be (77 ± 24) s in the experimental NMR volume, limited by leaks and field inhomogeneity. This represents good progress towards the eventual system for nEDM experiments where polarizations greater than 50% and T1, T2 relaxation times greater than 1000 s are expected.

Future fundamental physics experiments in neutron beta-decay require highly efficient detection of protons. Many of the experiments use electrostatic acceleration of the recoil protons into large-area silicon detectors for this purpose. A 30~keV proton accelerator was designed, created, and commissioned in order to characterize silicon detectors of this type. Final construction and initial results on the performance of the accelerator are presented. A unique aspect of the work is the use of a Penning ion generator as an ion source. The accelerator produced protons with momentum resolution ~1%. The ion source produced current stably, over a range of parameters, and over long periods of time. The accelerator achieved proton rates sufficient to calibrate silicon detectors.