UBC Theses and Dissertations
Measurement of the Lamb shift in muonium Fry, Charles Alan
This thesis describes the first measurement of the Lamb shift in n=2 muonium. The muonium atom is a hydrogen-like bound state of two leptons (µ⁺e⁻), both of which are believed to be point-like particles. The point-like nature of the constituent particles simplifies and reduces the uncertainty of the application of quantum electrodynamics (QED) to the calculation of the Lamb shift in the muonium atom. Measurements of the Lamb shift in hydrogen disagree with the predictions of theory by a few standard deviations; however, theoretical predictions also disagree with each other, partly because of difficulties associated with the treatment of the proton structure. Thus a measurement in the muonium system of similar precision to those already made in the hydrogen system will be a valuable test of QED. The present experiment is not intended to test QED. It is an investigation of the methods and techniques necessary to surmount the difficulties presented by the nature of muonium. The available number of muonium atoms is about 10⁺¹º times less than that of hydrogen used by Lamb in his first measurement. The value obtained for the n=2 muonium Lamb shift 1070⁺¹²₋₁₅ MHz. The uncertainty quoted is statistical at the 68% confidence level. Systematic effects were found to contribute to a further 2 MHz uncertainty.