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Related papers: The Linear Meson Model and Chiral Perturbation The…

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We analyse the extension of Chiral Perturbation Theory to describe a meson gas out of thermal equilibrium. For that purpose, we let the pion decay constant be a time-dependent function and work within the Schwinger-Keldysh contour…

High Energy Physics - Phenomenology · Physics 2016-09-06 A. Gomez Nicola

These lecture notes include the following topics. Chapter 1 deals with QCD and its global symmetries in the chiral limit, explicit symmetry breaking in terms of the quark masses, and the concept of Green functions and Ward identities…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Scherer , Matthias R. Schindler

We calculate finite size effects on nucleon masses in chiral perturbation theory. We confront the theoretical predictions with N_f=2 lattice results and discuss chiral extrapolation formulae.

High Energy Physics - Lattice · Physics 2009-09-29 A. Ali Khan , T. Bakeyev , M. Göckeler , T. R. Hemmert , R. Horsley , A. C. Irving , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

Effective field theory techniques are used to describe the interaction of heavy hadrons in a model independent way. Predictability is obtained by exploiting the symmetries of QCD. Heavy hadron chiral perturbation theory is reviewed and used…

High Energy Physics - Phenomenology · Physics 2007-05-23 Iain W. Stewart

We use one-loop chiral perturbation theory (ChPT) to compare lattice results for the K+ to pi+ pi0 decay amplitude with the experimental value. Three systematic effects: quenching, finite-volume effects, and the use of unphysical values of…

High Energy Physics - Lattice · Physics 2009-10-30 Maarten Golterman , Ka Chun Leung

We summarize the results of the SU(4) chiral meson Lagrangian approach to the cross section for J/psi breakup by pion and rho meson impact and suggest a new scheme for the introduction of formfactors for the meson-meson interaction. This…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Ivanov , Y. L. Kalinovsky , D. Blaschke , G. Burau

We report on recent nonperturbative techniques that combine the information of chiral Lagrangians (with and without resonances) with unitarity in coupled channels and other requirements of the S-matrix theory of the strong interactions. As…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. A. Oller , E. Oset , A. Ramos

The next-to-leading order chiral pion-nucleon Lagrangian contains seven finite low-energy constants. Two can be fixed from the nucleon anomalous magnetic moments and another one from the quark mass contribution to the neutron-proton mass…

High Energy Physics - Phenomenology · Physics 2016-09-06 V. Bernard , N. Kaiser , Ulf-G. Meißner

The electromagnetic corrections to the masses of the pseudoscalar mesons $\pi$ and $K$ are considered. We calculate in chiral perturbation theory the contributions which arise from resonances within a photon loop at order $O(e^2 m_q)$.…

High Energy Physics - Phenomenology · Physics 2009-10-28 Robert Baur , Res Urech

We have explored twisted mass LQCD (tmLQCD) analytically using chiral perturbation theory, including discretization effects up to O(a^2), and working at next-to-leading (NLO) order in the chiral expansion. In particular we have studied the…

High Energy Physics - Lattice · Physics 2009-11-10 Stephen R. Sharpe , Jackson M. S. Wu

Charm and bottom mesons and baryons are incorporated into a low energy chiral Lagrangian. Interactions of the heavy hadrons with light octet Goldstone bosons are studied in a framework which represents a synthesis of chiral perturbation…

High Energy Physics - Phenomenology · Physics 2010-11-01 Peter Cho

We extend chiral perturbation theory to study a meson gas out of thermal equilibrium. Assuming that the system is initially in equilibrium below the critical temperature and working within the Schwinger-Keldysh contour technique, we define…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Gomez Nicola , V. Galan-Gonzalez

The Chiral Confining Lagrangian, based on the chiral theory with quark degrees of freedom, is used to study the spectroscopy of scalar mesons. The formalism does not contain arbitrary fitting parameters and takes into account infinite…

High Energy Physics - Phenomenology · Physics 2020-06-24 M. S. Lukashov , Yu. A. Simonov

In the limit of vanishing up, down and strange quark masses, QCD exhibits a chiral symmetry. This symmetry is broken spontaneously to its vector subgroup, giving rise to Goldstone bosons. These acquire a small mass through the explicit…

High Energy Physics - Phenomenology · Physics 2024-12-31 Ulf-G. Meißner

We calculate the vector meson masses in $N_{\rm f} = 2+1$ Wilson chiral perturbation theory at next-to-leading order. Generalizing the framework of heavy vector meson chiral perturbation theory, the quark mass and the lattice cutoff…

High Energy Physics - Lattice · Physics 2009-11-11 S. Aoki , O. Baer , S. Takeda

In this talk we briefly describe some basic elements of chiral perturbation theory, $\chi PT$, and how the implementation of unitarity and other novel elements lead to a better expansion of the $T$ matrix for meson meson and meson baryon…

Chiral perturbation theory is extended to nonrelativistic systems with spontaneously broken symmetry. In the effective Lagrangian, order parameters associated with the generators of the group manifest themselves as effective coupling…

High Energy Physics - Phenomenology · Physics 2009-10-22 H. Leutwyler

I present a quick overview of the current status of Chiral perturbation theory in the meson sector. To illustrate the successes and some problems in the description of the phenomenology, I focus on a few selected examples that are relevant…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gilberto Colangelo

We examine the general lagrangian for baryon chiral perturbation theory with SU(3) flavor symmetry, up to the next-to-leading order. We consider both the strong and the weak interaction. The inverse of the baryon mass is treated as an…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. W. Bos , D. W. Chang , S. C. Lee , Y. C. Lin , H. H. Shih

Using quenched chiral perturbation theory we compute meson correlation functions at finite volume and fixed gauge field topology. We also present the corresponding analytical predictions for the unquenched theory at fixed gauge field…

High Energy Physics - Lattice · Physics 2008-11-26 P. H. Damgaard , M. C. Diamantini , P. Hernandez , K. Jansen