The search for new physics in B → K ℓ⁺ℓ^- and B → K νν using precise lattice QCD form factors

2022/10/19 by W. G. Parrott, Parrott, W. G., Chris Bouchard +3
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #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.2210.10898

openalex publication_date 2022/10/19 · openalex created_date 2022/10/24 · openalex updated_date 2026/07/28

Abstract

We present HPQCD's improved scalar, vector and tensor form factors for B → K semileptonic decays, using the heavy-HISQ formalism for more accurate normalisation of the weak currents. Working with masses close to the physical b on the finest ensemble and including three ensembles with physical light quarks, we cover the full physical q² range with good precision. Our uncertainties at q²=0 are a factor of three better than earlier work. We compare Standard Model observables using our form factors to experimental measurements for the rare flavour changing neutral current processes B → K ℓ⁺ℓ^- and B → K νν and discuss the significance of the tensions that arise.

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