2005/12/31 by Diego Guadagnoli, D. Guadagnoli, Federico Mescia +3 · 4 citations
Mathematics · Physics and Astronomy · #Boundary (topology) #Boundary value problem #Geometry #High-Energy Particle Collisions Research #Lattice (music) #Lattice QCD #Mathematical analysis #Mathematics #Momentum (technical analysis) #Momentum transfer #Particle physics #Particle physics theoretical and experimental studies #Periodic boundary conditions #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Scalar (mathematics) #Scattering #hep-lat
paper · pdf · doi:10.1103/physrevd.73.114504
published as Phys.Rev. D73 (2006) 114504 · latex 15 pages, 4 figures and 3 tables; modified intro and discussions of the results; version to appear in PRD
arxiv created 2006/05/25 · openalex publication_date 2006/06/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We apply twisted boundary conditions to lattice QCD simulations of three-point correlation functions in order to access spatial components of hadronic momenta different from the integer multiples of 2\ensuremathπ/L. We calculate the vector and scalar form factors relevant to the K\ensuremath→\ensuremathπ semileptonic decay and consider all the possible ways of twisting one of the quark lines in the three-point functions. We show that the momentum shift produced by the twisted boundary conditions does not introduce any additional noise and easily allows us to determine within a few percent of statistical accuracy the form factors at quite small values of the four-momentum transfer, which are not accessible when periodic boundary conditions are considered. The use of twisted boundary conditions turns out to be crucial for a precise determination of the form factor at zero-momentum transfer, when a precise lattice point sufficiently close to zero-momentum transfer is not accessible with periodic boundary conditions.