Phase ofεK′and the sign ofsinδ

Abstract

New Kobayashi-Maskawa angular regions characterized by $sin\delta <0\mathrm{}$ are explored. Such regions are found to satisfy all existing phenomenological constraints, and bear interesting implications for future phenomenology. Prior theoretical lower bounds on the magnitude of ${\epsilon }_K^{\prime }$ are respected by the new angular regions, but a change in sign provides the opportunity to confirm or eliminate the new regions in the forthcoming $\left|\frac{{\eta }_{00}}{{\eta }_{+-}}\right|$ experiments.