Precision Measurements with Complex Atoms

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

The project aims at table-top experimental investigation of fundamental symmetries of nature along three thrusts: (1) measuring atomic parity violation (APV) in ytterbium, (2) searching for spatio-temporal variation of the fine-structure "constant" alpha and APV in dysprosium, and (3) conducting discrete symmetry tests in barium. The three apparatus are well-positioned to perform APV measurements across a chain of isotopes (Ytterbium, Dysprosium, Barium), yielding information about how the neutron radius varies, with ramifications to supernovas, neutron stars, and the creation of heavy elements. These experiments provide a unique window into weak interactions within atomic nuclei. Our present understanding of the laws of Nature is largely based on the concepts of symmetry and invariance. For example, we generally assume that fundamental laws of physics do not change with time. Many symmetries of nature, however, are broken, for example, the symmetry between the actual world and its mirror image (the so-called left-right asymmetry a.k.a. parity violation). While experiments with high-energy colliders and astronomical observations provide powerful laboratories for the study of fundamental symmetries, small-scale table-top experiments such as the ones in this project can be competitive with other techniques in certain areas. Moreover, they are also capable of providing unique scientific information that is difficult to obtain by other means. Such small-scale experiments are ideal for training the new generation of hands-on scientists.