Semileptonic B → η,J/ψ transitions
Zhao-Qian Yao, Daniele Binosi, Zhu-Fang Cui, Craig D. Roberts
Abstract
Using a systematic, symmetry-preserving continuum approach to the Standard Model strong-interaction bound-state problem, we deliver parameter-free predictions for all semileptonic Bc→ηc,J/ψ transition form factors on the complete domains of empirically accessible momentum transfers. Working with branching fractions calculated therefrom, the following values of the ratios for τ over μ final states are obtained: Rηc=0.313(22) and RJ/ψ=0.242(47). Combined with other recent results, our analysis confirms a 2σ discrepancy between the Standard Model prediction for RJ/ψ and the single available experimental result.
Topics & Concepts
PhysicsParticle physicsSemileptonic decayStandard Model (mathematical formulation)Physics beyond the Standard ModelNuclear physicsBranching fractionMomentum (technical analysis)Statistical physicsBranching (polymer chemistry)Feynman graphWork (physics)Particle physics theoretical and experimental studiesQuantum Chromodynamics and Particle InteractionsQuantum and Classical Electrodynamics