New measurement of the 2S1/2-8D5/2 transition in atomic hydrogen, A

2021 Summer.Includes bibliographical references.High-precision spectroscopy of simple atoms provides input data that can be used to extract fundamental constants and to test Standard Model theory. Hydrogen, the simplest element, has played a historically significant role in the development of fundamental theory and, more recently, provides important data for the proton radius puzzle. In this thesis, we will describe a new measurement of the 2S1/2-8D5/2 transition on a cryogenic hydrogen beam. We will overview the measurement scheme and experimental apparatus, then present analysis and systematic characterization important to the spectroscopy. Finally, we will present our preliminary determination of the proton radius and the Rydberg constant using our value for the 2S1/2-8D5/2 combined with the previously measured 1S-2S transition