This project consists of a series of relatively small-scale experiments using lasers and atoms which will address fundamental questions about physics of the electroweak interaction as well as other possible symmetry-violating interactions. Recent atomic parity nonconservation (PNC) experiments in several elements have attained very high precision. However, before new experimental results can lead to fundamental insights, the effects of the complex atomic structure of the relevant atoms must be understood. In thallium, new atomic structure calculations presently underway have the potential to make this element a particularly important system for testing electroweak physics. Recently completed transition amplitude, and hyperfine splitting measurements, as well as Stark shift and Stark-induced amplitude measurements now underway in our laboratory provide some of the first high-precision atomic structure tests in this element. Experiments using very similar techniques will be undertaken in other atomic systems of potential importance to electroweak tests such as lead. These experiments make use of diode laser systems and thallium samples in heated vapor cells as well as an atomic beam apparatus. The experiments will serve as ideal research training for undergraduate physics majors, the large majority of whom attend graduate school in the physical sciences.
