Spin Precession - Listening to the Whisper of Spin About Fundamental Physics

by Prof. Koiciro Asahi (Tokyo Institute of Technology / RIKEN, Japan)

Thursday Sep 21, 2017, 4:30 PM → 5:30 PM Asia/Seoul

206호 (제1과학관)

Every fundamental particle, such as electron, photon, atoms and nuclei, is accompanied by spin, a quantum observable representing the angular momentum of particle’s rotation. The spin is quantum mechanical in its origin, but can be observed, oriented and even controlled in laboratory, and nowadays plays an important role in many facets of science and technology. In particular, one of its property, the electric dipole moment (EDM), is serving as a key observable that probes physics beyond the Standard Model of elementary particle physics.
After introducing the spin in a quantum mechanical way with a classical analogue in mind, we discuss how it moves under an applied magnetic field (spin precession). Then by taking as an example a case of the spin of a 129Xe nucleus,the experimental methods and setups are introducedt opolarize, detectandcontrolthespins.Aspin maser is formed with the polarized spins, aiming at pursuing the search for EDM in a Xe atom. The EDM is a peculiar yet intriguing observable, which is “forbidden” in the current theory of elementary particle physics, the Standard Model. We discuss how the sizes of EDMs, if determined experimentally, are related to new physics proposed beyond the Standard Model.