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Title: K{yields}{pi}{pi} Amplitudes from Lattice QCD with a Light Charm Quark

Abstract

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.

Authors:
;  [1];  [2];  [3];  [4];  [5]
  1. Department of Physics, CERN, TH Division, CH-1211 Geneva 23 (Switzerland)
  2. Departamento de Fisica Teorica and IFIC, Universidad de Valencia, E-46071 Valencia (Spain)
  3. Faculty of Physics, University of Bielefeld, D-33501 Bielefeld (Germany)
  4. DESY, Notkestrasse 85, D-22603 Hamburg (Germany)
  5. Institut fuer Kernphysik, Universitaet Mainz, D-55099 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 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.},
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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  • We discuss some aspects of the search for CP asymmetry in the three body B decays, revealed through the interference among neighbor resonances in the Dalitz plot. We propose a competitive method to extract the CKM {gamma} angle combining Dalitz plot amplitude analysis of B{sup {+-}}{yields}K{sup {+-}}{pi}{sup +}{pi}{sup -} and untagged B{sup 0}, B{sup 0}{yields}K{sub s}{pi}{sup +}{pi}{sup -}. The method also obtains the ratio and phase difference between the tree and penguin contributions from B{sup 0} and B{sup 0}{yields}K*{sup {+-}}{pi}{sup {+-}} decays and the CP asymmetry between B{sup 0} and B{sup 0}. From Monte Carlo studies of 100 K eventsmore » for the neutral mesons, we show the possibility of measuring {gamma}.« less
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