2013/11/10 by J. M. Flynn, Flynn, J. M., Patrick Fritzsch +18
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 #hep-lat
paper · pdf · doi:10.48550/arxiv.1311.2251
7 pages, 2 figures, presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, Germany
arxiv created 2013/11/10 · openalex publication_date 2013/11/10 · arxiv updated 2013/11/12 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
We report on a calculation of the B^*Bπ coupling in lattice QCD. The strong matrix element ⟨ B π| B^*⟩ is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HMχPT) for B-mesons. We carry out our calculation directly at the b-quark mass using a non-perturbatively tuned clover action that controls discretisation effects of order |pa| and (ma)n for all n. Our analysis is performed on RBC/UKQCD gauge configurations using domain wall fermions and the Iwasaki gauge action at two lattice spacings of a-1=1.73(3) GeV, a-1=2.28(3) GeV, and unitary pion masses down to 290 MeV. We achieve good statistical precision and control all systematic uncertainties, giving a final result for the HMχPT coupling gb = 0.569(48)stat(59)sys in the continuum and at the physical light-quark masses. This is the first calculation performed directly at the physical b-quark mass and lies in the region one would expect from carrying out an interpolation between previous results at the charm mass and at the static point.