K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark
Abstract
We compute the leadingorder lowenergy constants of the {delta}S=1 effective weak Hamiltonian in the quenched approximation of QCD with up, down, strange, and charm quarks degenerate and light. They are extracted by comparing the predictions of finitevolume chiral perturbation theory with lattice QCD computations of suitable correlation functions carried out with quark masses ranging from a few MeV up to half of the physical strange mass. We observe a {delta}I=1/2 enhancement in this corner of the parameter space of the theory. Although matching with the experimental result is not observed for the {delta}I=1/2 amplitude, our computation suggests large QCD contributions to the physical {delta}I=1/2 rule in the GIM limit, and represents the first step to quantify the role of the charmquark mass in K{yields}{pi}{pi} amplitudes. The use of fermions with an exact chiral symmetry is an essential ingredient in our computation.
 Authors:
 Department of Physics, CERN, TH Division, CH1211 Geneva 23 (Switzerland)
 Departamento de Fisica Teorica and IFIC, Universidad de Valencia, E46071 Valencia (Spain)
 Faculty of Physics, University of Bielefeld, D33501 Bielefeld (Germany)
 DESY, Notkestrasse 85, D22603 Hamburg (Germany)
 Institut fuer Kernphysik, Universitaet Mainz, D55099 Mainz (Germany)
 Publication Date:
 OSTI Identifier:
 20957677
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevLett.98.082003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; APPROXIMATIONS; CHIRAL SYMMETRY; CHIRALITY; CORRELATION FUNCTIONS; HAMILTONIANS; KAONS; MASS; MEV RANGE; PERTURBATION THEORY; PIONS; QUANTUM CHROMODYNAMICS; QUARKS
Citation Formats
Giusti, L., Pena, C., Hernandez, P., Laine, M., Wennekers, J., and Wittig, H. K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVLETT.98.082003.
Giusti, L., Pena, C., Hernandez, P., Laine, M., Wennekers, J., & Wittig, H. K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark. United States. doi:10.1103/PHYSREVLETT.98.082003.
Giusti, L., Pena, C., Hernandez, P., Laine, M., Wennekers, J., and Wittig, H. Fri .
"K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark". United States.
doi:10.1103/PHYSREVLETT.98.082003.
@article{osti_20957677,
title = {K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark},
author = {Giusti, L. and Pena, C. and Hernandez, P. and Laine, M. and Wennekers, J. and Wittig, H.},
abstractNote = {We compute the leadingorder lowenergy constants of the {delta}S=1 effective weak Hamiltonian in the quenched approximation of QCD with up, down, strange, and charm quarks degenerate and light. They are extracted by comparing the predictions of finitevolume chiral perturbation theory with lattice QCD computations of suitable correlation functions carried out with quark masses ranging from a few MeV up to half of the physical strange mass. We observe a {delta}I=1/2 enhancement in this corner of the parameter space of the theory. Although matching with the experimental result is not observed for the {delta}I=1/2 amplitude, our computation suggests large QCD contributions to the physical {delta}I=1/2 rule in the GIM limit, and represents the first step to quantify the role of the charmquark mass in K{yields}{pi}{pi} amplitudes. The use of fermions with an exact chiral symmetry is an essential ingredient in our computation.},
doi = {10.1103/PHYSREVLETT.98.082003},
journal = {Physical Review Letters},
number = 8,
volume = 98,
place = {United States},
year = {Fri Feb 23 00:00:00 EST 2007},
month = {Fri Feb 23 00:00:00 EST 2007}
}

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