2021/11/11 by C. T. H. Davies, D. Hatton, Davies, C. T. H. +7
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2111.06149
openalex publication_date 2021/11/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
As tests of QCD in the bottomonium system, we give the most accurate results to date for the ground-state hyperfine splitting and the Υ leptonic width from full lattice QCD. These quantities are both accurately known from experiment, so can provide a good test of b physics, but previous lattice results have been rather imprecise. We also test the impact on these quantities of the b quark's electric charge. Our results are: MΥ-Mηb = 57.5(2.3)(1.0) MeV (where the second uncertainty comes from neglect of quark-line disconnected correlation functions) and decay constants, fηb = 724(12) MeV and fΥ = 677.2(9.7) MeV, giving Γ(Υ→ e+e-) = 1.292(37)(3) keV. We also give a new determination of the ratio of the masses for b and c quarks that is completely nonperturbative in lattice QCD and includes the calculation of QED effects for the first time. This gives a result for the b quark mass of mb(mb,nf=5) = 4.202(21) GeV.