Novel approaches to determine B± and B0 meson production fractions

Abstract

We propose novel methods to determine the ϒ(4S)→B+B− and ϒ(4S)→B0B¯0 decay rates. The precision to which they and their ratio are known yields at present a limiting uncertainty around 2% in measurements of absolute B decay rates, and thus in a variety of applications, such as precision determinations of elements of the Cabibbo-Kobayashi-Maskawa matrix and flavor-symmetry relations. The new methods we propose are based in one case on exploiting the ϒ(5S) datasets, in the other case on the different average number of charged tracks in B± and B0 decays. We estimate future sensitivities using these methods and discuss possible measurements of fd/fu at the (HL-)LHC. Published by the American Physical Society 2024