Automated production and purification of hyperpolarized xenon gas
| dc.contributor.author | Lang, Michael | |
| dc.contributor.author | Lang, Michael | |
| dc.contributor.examiningcommittee | Mammei, Juliette (Physics and Astronomy) Blunden, Peter (Physics and Astronomy) Hollett, Joshua (Chemistry) Sarty, Gordon (University of Saskatchewan) | en_US |
| dc.contributor.supervisor | Bidinosti, Christopher (Physics and Astronomy) Martin, Jeffery (Physics and Astronomy) | en_US |
| dc.date.accessioned | 2020-09-07T22:12:23Z | |
| dc.date.available | 2020-09-07T22:12:23Z | |
| dc.date.copyright | 2020-05-10 | |
| dc.date.issued | 2020 | en_US |
| dc.date.submitted | 2020-05-11T00:24:50Z | en_US |
| dc.degree.discipline | Physics and Astronomy | en_US |
| dc.degree.level | Doctor of Philosophy (Ph.D.) | en_US |
| dc.description.abstract | Precision measurements of the neutron electric dipole moment (nEDM) typically require a comagnetometer to provide real time, in-situ monitoring of the magnetic field in the neutron cell. A proposed future upgrade to the TRIUMF Ultra Cold Advanced Neutron (TUCAN) nEDM experiment may include an optical atomic comagnetometer based on the spin-precession of hyperpolarized129-Xe gas. This requires the delivery of purified, polarized 129-Xe gas to the neutron cell for each Ramsey cycle of the experiment. The high duty cycle of the nEDM experiment and the environment of Meson Hall at TRIUMF during neutron production demands the fully automated production and purification of hyperpolarized 129-Xe gas without human intervention. This thesis presents the development of apparatus for the automated production and purification of hyperpolarized xenon gas. This system performs (1) the polarization of 129-Xe gas by spin-exchange optical pumping (SEOP), (2) the purification of the xenon via cryogenic separation, and (3) the delivery of the polarized and purified gas to an NMR apparatus that serves both as a means of polarization characterization and as a proxy for delivery to a remote experiment. An existing 129-Xe polarizer was retrofit and fully calibrated for the production of hyperpolarized 129-Xe in this work. The custom-built purification apparatus comprises liquid nitrogen dispensing, a permanent magnet Halbach array, a custom glass cold trap, a heating system, gas flow control, and associated electronics and software for hands-free operation. The NMR apparatus, also designed and built as part of this work, includes a homebuilt Faraday cage, RF coils, and electronics, enabling the quantification of 129-Xe polarization before and after purification. We observed a relaxation rate of 1.3 hours for frozen xenon stored in the cold trap, and polarization recovery rates as high as 86% for purified xenon collected at a flow rate of 0.4 SLM over 675 s. We also observed an increase in percent polarization recovered during purification for larger quantities of accumulated xenon. We demonstrated the ability to perform consistent, automated, hands-free xenon purification with our apparatus involving no human intervention. | en_US |
| dc.description.note | October 2020 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/34963 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Hyperpolarized xenon comagnetometry | en_US |
| dc.title | Automated production and purification of hyperpolarized xenon gas | en_US |
| dc.title.alternative | Application to 129-xe comagnetometry for the nEDM experiment at TRIUMF | en_US |
| dc.title.alternative | Application to 129-Xe comagnetometry for the nEDM experiment at TRIUMF | en_US |
| dc.type | doctoral thesis | en_US |