Nagoya University
Theoretical Elementary Particle Physics Laboratory

Date&Time Thu Jul 16 2020 (10:00 - 11:00)
Masaaki Tomii
Affiliation Connecticut U.
Title Direct CP violation and the \Delta I = 1/2 rule in K \to \pi\pi decay from the Standard Model
Abstract I discuss our recent article [arXiv:2004.09440] of a lattice QCD calculation of the \Delta I=1/2 rule, K \to \pi\pi decay amplitude A_0 and \verepsilon', the measure of direct CP violation in K \to \pi\pi decay. This quantity is highly sensitive to new sources of CP violation that might help to explain the matter/antimatter asymmetry in the observable Universe. This calculation substantially improves on the previous results [Phys.Rev.Lett. 115 (2015) 21, 212001], including nearly four times the statistics and numerous technical improvements allowing us to more reliably isolate the \pi\pi ground-state and more accurately relate the lattice operators to those defined in the Standard Model.