<p> A single electron in a quantum cyclotron provides the most precise measurement of the electron magnetic moment, given in units of the Bohr magneton by <i> g</i>/2 = 1.001 159 652 180 73 (28) [0.28 ppt]. The most precise determination of the fine structure constant comes from combining this measurement with Standard Model theory, yielding α<sup>-1</sup> = 137.035 999 173 (34) [0.25 ppb], limited by the experimental uncertainty of the electron <i> g</i>-value. The most stringent test of CPT symmetry in leptons comes from comparing the electron and positron magnetic moments, limited by the positron uncertainty at 4.2 ppt. A new high-stability apparatus has been built and commissioned for improved measurements of the electron and positron magnetic moments, a greatly improved test of lepton CPT symmetry, and an improved determination of the fine structure constant. These new measurements require robust positron loading from a retractable radioactive source that is small enough to avoid compromising the high-precision environment of our experiment. The design and implementation of such a scheme is a central focus of this work. Robust positron loading at a rate of 1-2 e<sup>+</sup>/min from a 6.5 μCi <sup> 22</sup>Na source has been demonstrated.</p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:3566927 |
| Date | 09 August 2013 |
| Creators | Hoogerheide, Shannon Michelle Fogwell |
| Publisher | Harvard University |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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