English
Related papers

Related papers: Chiral Perturbation Theory and Unitarization

200 papers

We review the unitarization of Chiral Perturbation Theory with dispersion relations and how it describes meson-meson scattering data, generating light resonances whose mass, width and nature can be related to QCD parameters like quark…

High Energy Physics - Phenomenology · Physics 2019-08-12 J. R. Pelaez , J. Nebreda , G. Rios

These lectures describe the use of effective field theories to extrapolate results from the parameter region where numerical simulations of lattice QCD are possible to the physical parameters (physical quark masses, infinite volume,…

High Energy Physics - Lattice · Physics 2007-05-23 Stephen. R. Sharpe

The neutron-neutron scattering length a_nn provides a sensitive probe of charge-symmetry breaking in the strong interaction. Here we summarize our recent efforts to use chiral perturbation theory in order to systematically relate a_nn to…

Nuclear Theory · Physics 2009-04-17 A. Gardestig , D. R. Phillips

We study meson-baryon scattering with strangeness -1 in unitary chiral perturbation theory. Ten coupled channels are considered in our work, namely $\pi^0 \Lambda$, $\pi^0 \Sigma^0$, $\pi^- \Sigma^+$, $\pi^+ \Sigma^-$, $K^- p$, $\bar{K}^0…

High Energy Physics - Phenomenology · Physics 2013-11-15 Zhi-Hui Guo , J. A. Oller

We construct the generating functional of two flavor chiral perturbation theory including the effects of virtual photons in the one loop approximation. As an application, we calculate the electromagnetic corrections to the elastic $\pi\pi$…

High Energy Physics - Phenomenology · Physics 2009-10-30 Ulf-G. Meißner , G. Müller , S. Steininger

We present technical details of the evaluation of the elastic pi-pi scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the two-loop order and on the evaluation of…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. Bijnens , G. Colangelo , G. Ecker , J. Gasser , M. E. Sainio

In a recent work on low energy pion-nucleon scattering, instead of using chiral perturbation theory (ChPT) amplitude, we started from a pion-nucleon {\it soft-pion} result and used elastic unitarity directly as a dynamical constraint to…

High Energy Physics - Phenomenology · Physics 2009-11-07 Isabela P. Cavalcante , J. Sa Borges

Combining large $N_C$ techniques and partial wave dispersion theory to analyze the $\pi\pi$ scattering, without relying on any explicit resonance lagrangian, some interesting results are derived: (a) a general KSRF relation including the…

High Energy Physics - Phenomenology · Physics 2009-11-13 Zhi-Hui Guo

A general prescription for the construction of $\pi \pi$ interaction potentials which preserve scattering length constraints from chiral symmetry when iterated in scattering equations is derived. The prescription involves only minor…

Nuclear Theory · Physics 2009-10-28 R. Rapp , J. W. Durso , J. Wambach

I review the status of chiral perturbation theory in the one-nucleon sector and give some predictions to be tested. I then discuss various methods to go to higher energies (inclusion of the Delta(1232), dispersion relations) and also to…

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

There has recently been an intense activity in the study of finite volume effects by means of chiral perturbation theory. In this contribution I review recent work in this field both for the epsilon-- (Mpi L \lesssim 1) and the p--regime…

High Energy Physics - Lattice · Physics 2009-11-10 Gilberto Colangelo

In the framework of an effective chiral theory of mesons, pi K scattering is stydied. The scattering lengths, phase shifts, and cross sections are calculated. Theoretical results agree well with data. There is no new parameter in this…

High Energy Physics - Phenomenology · Physics 2014-11-17 Bing An Li , Dao-neng Gao , Mu-lin Yan

We perform a complete one-loop calculation of meson-meson scattering, and of the scalar and pseudoscalar form factors in U(3) chiral perturbation theory with the inclusion of explicit resonance fields. This effective field theory takes into…

High Energy Physics - Phenomenology · Physics 2015-06-04 Zhi-Hui Guo , J. A. Oller , J. Ruiz de Elvira

I consider some selected topics in chiral perturbation theory (CHPT). For the meson sector, emphasis is put on processes involving pions in the isospin zero S-wave which require multi-loop calculations. The advantages and shortcomings of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Ulf-G. Meißner

We discuss the recent literature on the treatment of final state interactions in K -> pi pi. Various approaches are compared and particular emphasis is given to the possibility of combining dispersive methods with lattice input. Recent…

High Energy Physics - Lattice · Physics 2009-11-07 Gilberto Colangelo

We review the large Nc behavior of light scalar and vector resonances generated from unitarized meson-meson scattering amplitudes at one loop in Chiral Perturbation Theory. The vectors nicely follow the behavior expected for qqbar states,…

High Energy Physics - Phenomenology · Physics 2009-11-11 J. R. Pelaez

We provide a short introduction to the one-nucleon sector of chiral perturbation theory and address the issue of power counting and renormalization. We discuss the infrared regularization and the extended on-mass-shell scheme. Both allow…

High Energy Physics - Phenomenology · Physics 2015-06-03 Stefan Scherer

We study the hadronic $\eta^{\prime}\to\eta\pi\pi$ decays within the framework of $U(3)_{L}\otimes U(3)_{R}$ Chiral Perturbation Theory including resonance states and the complete one-loop corrections. The amplitude is projected in partial…

High Energy Physics - Phenomenology · Physics 2018-10-17 Sergi Gonzàlez-Solís , Emilie Passemar

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

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

$\tau\to\pi\pi\nu$, $\tau\to\pi K\nu$, $\tau\to K\eta\nu$, $\tau\to 3\pi\nu$ and $\tau\to \pi\pi K\nu$ have been investigated using chiral symmetry with dispersion relation in agreement with the unitarity condition.

High Energy Physics - Phenomenology · Physics 2008-02-03 Larbi Beldjoudi , Tran Truong