English
Related papers

Related papers: Chiral low-energy constants L_10 and C_87 from had…

200 papers

Based on the AdS/CFT correspondence we study the breaking of the chiral symmetry in QCD using a simple five dimensional model. The model gives definite predictions for the spectrum of vector mesons, their decay constants and interactions as…

High Energy Physics - Phenomenology · Physics 2008-11-26 Leandro Da Rold , Alex Pomarol

We present a brief (mainly bibliographical) report on recently performed calculations of terms of order O(\alpha_s^4 n_f^2) and O(\alpha_s^4 n_f^2 m_q^2) for hadronic Z and \tau decay rates. A few details about the analytical evaluation of…

High Energy Physics - Phenomenology · Physics 2009-03-16 P. A. Baikov , K. G. Chetyrkin , J. H. Kuehn

We study two and three meson decays of the tau lepton within the framework of the Resonance Chiral Theory, that is based on the following properties of QCD: its chiral symmetry in the massless case, its large-N_C limit, and the asymptotic…

High Energy Physics - Phenomenology · Physics 2009-08-04 P. Roig

We have performed fits of the pseudoscalar masses and decay constants, from a variety of RBC-UKQCD domain wall fermion ensembles, to $SU(2)$ partially quenched chiral perturbation theory at next-to leading order (NLO) and next-to-next-to…

High Energy Physics - Lattice · Physics 2016-03-23 P. A. Boyle , N. H. Christ , N. Garron , C. Jung , A. Jüttner , C. Kelly , R. D. Mawhinney , G. McGlynn , D. J. Murphy , S. Ohta , A. Portelli , C. T. Sachrajda

We propose a general method to obtain accurate estimates for some of the "low-energy constants" in the one-loop effective chiral Lagrangian by means of simulating lattice QCD. In particular, the method is sensitive to those constants whose…

High Energy Physics - Lattice · Physics 2011-02-01 Jochen Heitger , Rainer Sommer , Hartmut Wittig

The values of the low-energy constants (LECs) are very important in the chiral perturbation theory. This paper adopts a Bayesian method with the truncation errors to globally fit eight next-to-leading order (NLO) LECs $L_i^r$ and…

High Energy Physics - Phenomenology · Physics 2024-08-21 Hao-Xiang Pan , De-Kai Kong , Qiao-Yi Wen , Shao-Zhou Jiang

After a brief introduction to chiral perturbation theory, the effective field theory of the standard model at low energies, two recent applications are reviewed: elastic pion-pion scattering to two-loop accuracy and the complete…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gerhard Ecker

We use both old and new theoretical developments in QCD dispersion relation constraints on the scalar form factor in the decay K --> \pi l \nu_l to obtain constraints on the strange quark mass. The perturbative QCD side of the calculation…

High Energy Physics - Phenomenology · Physics 2014-11-17 Richard F. Lebed , Karl Schilcher

I give a very short introduction to Chiral Perturbation Theory and an overview of the next-to-next-to-leading order three-flavour calculations done. I discuss those relevant for an improvement in the accuracy of the measurement of $V_{us}$…

High Energy Physics - Phenomenology · Physics 2010-11-23 Johan Bijnens

The leading order low energy parameters like the pion decay constant or the quark condensate are well-known from "classical" low energy theorems and experiments. It is a challenge, however, to find these parameters based exclusively on an…

High Energy Physics - Lattice · Physics 2007-05-23 Christof Gattringer , Philipp Huber , C. B. Lang

Basic chiral QCD parameters (the pion decay constant, the quark and gluon condensates, the dynamically generated quark mass, etc) as well as the vacuum energy density (up to the sign, by definition, the bag constant) have been calculated…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Gogohia , Gy. Kluge , M. Prisznyák

The coupling constants of the order $p^2$ low-energy weak effective lagrangian can be determined from the $K\to\pi$ and $K\to 0$ weak matrix elements, choosing degenerate quark masses for the first of these. However, for typical values of…

High Energy Physics - Lattice · Physics 2009-10-31 Maarten Golterman , Elisabetta Pallante

The effective chiral Lagrangian in both nonlocal form $L_{ECCL}$ and standard local form $L_{ECL}$ are derived in QCD using the confining kernel, obtained in the vacuum correlator formalism. As a result all coefficients of $L_{ECL}$ can be…

High Energy Physics - Phenomenology · Physics 2016-07-20 Yu. A. Simonov

In the framework of the instanton vacuum model we make expansion over the current mass $m$ and number of colors $N_c$ and evaluate ${\cal O}(1/N_c, m, m/N_c, m \ln m/N_c)$-corrections to the dynamical quark mass $M$, the quark condensate…

High Energy Physics - Phenomenology · Physics 2008-12-01 M. Musakhanov

By matching 1/m^2 divergences in finite-volume two-point correlation functions of the scalar or pseudoscalar densities with those obtained in chiral perturbation theory, we derive a relation between the Dirac operator zero-mode…

High Energy Physics - Lattice · Physics 2009-11-10 L. Giusti , P. Hernandez , M. Laine , P. Weisz , H. Wittig

We study the chiral logarithms in $\Delta S=1$ kaon decay amplitudes from new flavor physics in beyond-standard-model theories. We systematically classify the chiral structures of dimension-5, 6 and 7 effective QCD operators constructed out…

High Energy Physics - Phenomenology · Physics 2010-04-23 Panying Chen , Hongwei Ke , Xiangdong Ji

In a wide class of holographic models described by the Yang-Mills and Chern-Simons terms, we derive all the ${\cal O}(p^6)$ Chiral Perturbation Theory low-energy constants. Various model-independent relations exist among the constants up to…

High Energy Physics - Phenomenology · Physics 2015-06-11 Fen Zuo

Starting from the study of the low-energy and high-energy behaviours of the QCD three-point functions <VAP>, <VVP> and <AAP>, several O(p^6) low-energy constants of the chiral Lagrangian are evaluated within the framework of the lowest…

High Energy Physics - Phenomenology · Physics 2009-01-07 Marc Knecht , Andreas Nyffeler

In the low energy region chiral perturbation theory including virtual photons is used to derive the structure of the generating functional. The work we do is performed within the three flavor framework and reaches up to next-to-leading…

High Energy Physics - Phenomenology · Physics 2007-05-23 Anders Pinzke

We investigate the numerical values of the low-energy constants in the chiral effective Lagrangian for the interactions between the charmed mesons and the lightest pseudoscalar mesons, the Goldstone bosons of the spontaneous breaking of…

High Energy Physics - Phenomenology · Physics 2016-12-07 Meng-Lin Du , Feng-Kun Guo , Ulf-G. Meißner , De-Liang Yao