K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark
- Department of Physics, CERN, TH Division, CH-1211 Geneva 23 (Switzerland)
- Departamento de Fisica Teorica and IFIC, Universidad de Valencia, E-46071 Valencia (Spain)
- Faculty of Physics, University of Bielefeld, D-33501 Bielefeld (Germany)
- DESY, Notkestrasse 85, D-22603 Hamburg (Germany)
- Institut fuer Kernphysik, Universitaet Mainz, D-55099 Mainz (Germany)
We compute the leading-order low-energy 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 finite-volume 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 charm-quark mass in K{yields}{pi}{pi} amplitudes. The use of fermions with an exact chiral symmetry is an essential ingredient in our computation.
- OSTI ID:
- 20957677
- Journal Information:
- Physical Review Letters, Vol. 98, Issue 8; Other Information: DOI: 10.1103/PhysRevLett.98.082003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
Similar Records
Domain wall fermion QCD with the exact one flavor algorithm
Charmed and light pseudoscalar meson decay constants from four-flavor lattice QCD with physical light quarks