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Related papers: Low-Energy Constants from Resonance Chiral Theory

200 papers

Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models including both a light Higgs-like boson and massive spin-1 resonances are not in conflict with experimental constraints on the oblique S and…

High Energy Physics - Phenomenology · Physics 2016-02-17 Ignasi Rosell , Antonio Pich , Joaquin Santos , Juan Jose Sanz-Cillero

We present in this talk the recent investigation of the effective weak chiral Lagrangian within the framework of the instanton-induced chiral quark model. The low energy constants in leading order $g_8$ and $g_{27}$, and their ratio are…

High Energy Physics - Phenomenology · Physics 2009-10-31 Mario Franz , Hyun-Chul Kim , Klaus Goeke

The chiral Lagrangian for Goldstone boson scattering is a power series expansion in numbers of derivatives. Each successive term is suppressed by powers of a scale, $\Lambda_\chi$, which must be less than of order $4\pi f/\sqrt{N}$ where…

High Energy Physics - Phenomenology · Physics 2013-11-13 R. Sekhar Chivukula , M. Dugan , M. Golden

The systematic effective Lagrangian method was first formulated in the context of the strong interaction: chiral perturbation theory (CHPT) is the effective theory of Quantum Chromodynamics (QCD). It was then pointed out that the method can…

High Energy Physics - Phenomenology · Physics 2014-04-30 Christoph P. Hofmann

Using a sequence of rational approximants and the large-Nc limit of QCD, we estimate the value of the low-energy constant C_87 which appears in the Lagrangian of Chiral Perturbation Theory at O(p^6).

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Masjuan , S. Peris

We derive a microscopic relativistic point-coupling model of nuclear many-body dynamics constrained by in-medium QCD sum rules and chiral symmetry. The effective Lagrangian is characterized by density dependent coupling strengths,…

Nuclear Theory · Physics 2009-11-10 P. Finelli , N. Kaiser , D. Vretenar , W. Weise

The meson-exchange current in nuclei, a long-standing problem in nuclear physics, is described in modern theory of strong interactions, namely, QCD expressed in terms of effective chiral Lagrangian field theory. Some old results are given a…

Nuclear Theory · Physics 2007-05-23 Mannque Rho

The processes involving low energy $\bar{K}N$ and $Y\pi$ interactions (where $Y= \Sigma$ or $\Lambda$) are studied in the framework of heavy baryon chiral perturbation theory with the $\Lambda$(1405) resonance appearing as an independent…

Nuclear Theory · Physics 2008-11-26 B. Krippa , J. T. Londergan

We derive the the effective lagrangian that describes the interactions among vector, axial-vector mesons and pseudoscalars starting from the extended chiral quark model (ECQM). The results for the low-energy constants of this effective…

High Energy Physics - Phenomenology · Physics 2008-11-26 Giancarlo D'Ambrosio , Domenec Espriu

I review some basic facts about the chiral limit of QCD. This allows to formulate an effective field theory below the chiral symmetry breaking scale, chiral perturbation theory (CHPT). I show that for threshold reactions, the spectrum of…

High Energy Physics - Phenomenology · Physics 2008-02-03 Ulf-G. Meißner

It is shown how a chiral Lagrangian framework can be used to derive relationships connecting quark-level QCD correlation functions to mesonic-level two-point functions. Crucial ingredients of this connection are scale factor matrices…

High Energy Physics - Phenomenology · Physics 2016-01-12 Amir H. Fariborz , A. Pokraka , T. G. Steele

The lectures review some of the basic concepts relevant for an understanding of the low energy properties of the strong interactions: chiral symmetry, spontaneous symmetry breakdown, Goldstone bosons, quark condensate. The effective field…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. Leutwyler

The implementation of tensor sources in Chiral Lagrangians allows the computation of Green functions and form factors involving tensor currents, that is, quark bilinears of the form \bar{q}_i\sigma^{\mu\nu}q_j. Whereas only four new terms…

High Energy Physics - Phenomenology · Physics 2011-07-19 Vicent Mateu

An effective hadronic lagrangian consistent with the symmetries of quantum chromodynamics and intended for applications to finite-density systems is constructed. The degrees of freedom are (valence) nucleons, pions, and the low-lying…

Nuclear Theory · Physics 2009-10-30 R. J. Furnstahl , Brian D. Serot , Hua-Bin Tang

The low lying spectrum of QCD in the delta-regime is calculated here in chiral perturbation theory up to NNL order. The spectrum has a simple form in terms of the pion decay constant F and a combination of the low energy constants Lambda1…

High Energy Physics - Theory · Physics 2010-03-25 P. Hasenfratz

I discuss a low-energy effective field theory which permits the full treatment of isospin-breaking effects in semileptonic weak interactions. In addition to the pseudoscalars and the photon, also the light leptons have to be included as…

High Energy Physics - Phenomenology · Physics 2011-04-15 H. Neufeld

This paper discusses a general class of ladder resummation inspired hadronic approximations. It is found that this approach naturally reproduces many successes of single meson per channel saturation models (e.g. VMD) and NJL based models.…

High Energy Physics - Phenomenology · Physics 2009-11-10 Johan Bijnens , Elvira Gamiz , Edisher Lipartia , Joaquim Prades

Chiral perturbation theory, the low energy effective theory of the strong interactions for the light pseudoscalar degrees of freedom, is based on effective Lagrangian techniques and is an expansion in the powers of the external momenta and…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Ananthanarayan , P. Büttiker

We compute the free energy in the presence of a chemical potential coupled to a conserved charge in effective O($n$) scalar field theory (without explicit symmetry breaking terms) to NNL order for asymmetric volumes in general…

High Energy Physics - Lattice · Physics 2016-05-25 Ferenc Niedermayer , Peter Weisz

These lectures give an introduction to baryon chiral perturbation theory. I show in detail how to construct the chiral effective pion-nucleon Lagrangian in the one loop approximation. Particular emphasis is put on the physics related to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulf-G. Meißner