RUI: Precise Atomic Structure Measurements and Tests of Fundamental Physics in Group IIIA atoms

Williams College, Williamstown MA

Investigators

Abstract

In this project, carefully controlled lasers will be used to probe the detailed atomic structure of a class of heavy atoms including thallium and indium with unprecedented precision. Atoms, quintessential quantum mechanical objects, have long been used to confirm and test quantum theory. But in recent years, with advances in laser, optical, and signal processing technology, extremely precise experiments on certain heavy atoms have yielded insights into physics more commonly associated with elementary particles and large accelerators. Such tests of fundamental particle physics in these "table-top" experiments can only occur through both precise experiments and also sophisticated quantum mechanical calculations of these many-electron systems. Experiments in this laboratory using atoms in both heated vapor cells and atomic beam apparatus will be completed to test the accuracy of this cutting-edge atomic theory. Finally, an experiment will probe possible violations of "time-reversal" invariance in thallium atoms, which would be the signal for new physics beyond the current Standard Model of particle physics. At Williams College, these experiments serve as ideal research training for undergraduate physics students at every stage of their education. In the absence of graduate students, these students grow to become fully engaged junior colleagues. Since NSF support for this work began in 1998, a dozen students have become co-authors on journal publications, and twenty young scientists who received their first exposure to research in this laboratory have completed or are now enrolled in Ph.D. programs in physics and related fields. Students take active, central roles in completing laboratory projects through which they develop expertise with optics and lasers, electronics and control systems, as well as sophisticated data analysis procedures. Because of the relatively small physical scale of the research, they can appreciate the entirety of the experimental effort, gain valuable, specific experimental skills, and yet participate in an exciting cutting-edge research field which uses atoms to test physical theory at its most basic level. A continuing effort will be made to include students in this research at this crucial early point in their undergraduate years, as they begin to make longer-term career choices.