PM: RUI: High Precision Spectroscopy for Tests of QED

Smith College, Northampton MA

Investigators

Abstract

The aim of this project aligns well with the goal of fundamental atomic physics, which is to understand the complex interactions and inner workings of the atom. Specifically, this project tests our best theoretical model, known as the Standard Model of Particle Physics, by measuring properties of beryllium, boron, nitrogen, and oxygen. Our knowledge of atomic systems is driven by both experimental and theoretical results. The lightest elements (hydrogen, helium, lithium, and a few properties of beryllium) have been well studied both experimentally and theoretically. The proposed atoms the Williams lab is going to study are more complex and difficult to model. As the computations grow more complex, it becomes essential to provide experimental results to both check those calculations and determine which theoretical models correctly describe these multi-electron systems. This project will greatly improve upon current experimental measurements to validate the predictions of the part of the Standard Model of Particle Physics known as quantum electrodynamics, as well as provide information about the nuclear and electronic structure of the atoms. The project will also provide the atomic and nuclear physics communities with enough high precision experimental data to assist theorists in their calculations, which will then serve to drive the advancement of theory for quite a few years. In addition to this scientific impact, the Williams lab will create a course-based undergraduate research experience (CURE) whose goals are to 1) provide a robust research experience for nine undergraduate students each year and 2) train the next generation of scientists to perform high precision spectroscopy. Technical description: The Williams lab will measure the absolute transition energies as well as hyperfine coupling constants, when applicable, of a variety of states in the light atoms to provide invaluable feedback to theorists who are in the pursuit of developing high precision multi-electron models. Combined with theoretical predictions, the results will serve to test the accuracy of quantum electrodynamics. Planned spectroscopic measurements will be performed on a number of triplet states in neutral beryllium-9, two transitions in the stable isotopes of boron, and a variety of states in nitrogen and oxygen. In addition, the Williams lab will develop a novel, sensitive spectroscopic technique to measure the absolute energy of states that are weakly coupled to the ground state. This new technique, which is an extension of the well-known NICE-OHMS method, may develop into exciting future experiments including the first magneto-optical trap (MOT) of neutral oxygen and the first vapor cell krypton MOT. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.