2018/12/20 by Peter A. Boyle, Boyle, Peter A, Luigi Del Debbio +11 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1812.08791
openalex publication_date 2018/12/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present results for the SU(3) breaking ratios of decay constants fDs/fD and fBs/fB and - for the first time with physical pion masses - the ratio of bag parameters BBs/BBd, as well as the ratio ξ, forming the ratio of the nonpeturbative contributions to neutral B(s) meson mixing. Our results are based on Lattice QCD simulations with chirally symmetric 2+1 dynamical flavors of domain wall fermions. Eight ensembles at three different lattice spacing in the range a = 0.11 - 0.07 fm enter the analysis two of which feature physical light quark masses. Multiple heavy quark masses are simulated ranging from below the charm quark mass to half the bottom quark mass. The SU(3) breaking ratios display a very benign heavy mass behaviour allowing for extrapolation to the physical bottom quark mass. The results in the continuum limit including all sources of systematic errors are fDs/fD = 1.1740(51)stat(+68-68)sys, fBs/fB = 1.1949(60)stat(^+\hphantom095-175)sys, BBs/BBd = 0.9984(45)stat(+80-63)sys and ξ= 1.1939(67)stat(^+\hphantom095-177)sys. Combining these with experimentally measured values we extract the ratios of CKM matrix elements |Vcd/Vcs| = 0.2164(57)exp(+12-12)lat and |Vtd/Vts| = 0.20329(41)exp(+162-301)lat.