English
Related papers

Related papers: Alternative Large Nc Schemes and Chiral Dynamics

200 papers

We perform a complete calculation of the pion-kaon scattering amplitude in Chiral Perturbation Theory at finite temperature, paying particular attention to the analytic structure of the amplitude and the main differences with respect to the…

High Energy Physics - Phenomenology · Physics 2023-08-30 Angel Gómez Nicola , Jacobo Ruiz de Elvira , Andrea Vioque-Rodríguez

We consider in details the dual models for the Goldstone mesons (pions) scattering in the presence of the explicit chiral symmetry breaking caused by non-zero current quark mass. New method of incorporation of the quark masses into the dual…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. V. Polyakov , G. Weidl

We present a determination of the pion-nucleon sigma-term based on a novel analysis of the $\pi N$ scattering amplitude in Lorentz covariant baryon chiral perturbation theory renormalized in the extended-on-mass-shell scheme. This…

High Energy Physics - Phenomenology · Physics 2015-06-03 J. Martin Camalich , J. M. Alarcon , J. A. Oller

In recent years, detailed studies of three-pion systems have become possible in lattice QCD. This has in turn led to interest in 3-to-3 scattering of pions in the chiral perturbation theory framework. In addition to being an interesting…

High Energy Physics - Phenomenology · Physics 2023-10-12 Jorge Baeza-Ballesteros , Johan Bijnens , Tomáš Husek , Fernando Romero-López , Stephen R. Sharpe , Mattias Sjö

In the first part of the talk, I review what we know (or rather do not know) about the structure of the QCD vacuum in the presence of strange quarks. Chiral perturbation theory allows to study reactions of pions and kaons and to further…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ulf-G. Meißner

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

We compute pion-nucleon scattering at tree-level within a gauged linear sigma model which contains the nucleon and its chiral partner. Such an investigation in principle allows to make definite predictions as to whether the main…

Nuclear Theory · Physics 2010-11-26 Susanna Wilms , Francesco Giacosa , Dirk H. Rischke

After contrasting the low energy effective theory for the baryon sector with one for the Goldstone sector, I use the example of pion nucleon scattering to discuss some of the progress and open issues in baryon chiral perturbation theory.

High Energy Physics - Phenomenology · Physics 2007-05-23 Thomas Becher

A new tool which combines chiral perturbation theory and unitarity in coupled channels is applied with success to the study of the meson-meson interaction, extending the theoretical predictions up to sqrt{s} = 1.2 GeV, hence improving…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Oset , J. A. Oller , J. R. Peláez , Chiang Huan Ching , M. J. Vicente Vacas

In the near future, the DIRAC collaboration will measure pion-pion scattering lengths with great precision. Those measurements are likely to shed some light on the problem of the size of the chiral quark-antiquark condensate. Although it is…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Dobado , J. R. Pelaez

We report on our recent results in the study of the chiral extrapolation of the phase-shifts in elastic pion-pion scattering, using both standard and unitarized ChPT to one and two loops. In the standard ChPT approach, limited to low…

High Energy Physics - Phenomenology · Physics 2011-08-31 J. Nebreda , J. R. Pelaez , G. Rios

Recent attempts to determine the pion polarizability by dispersion relations yield values that disagree with the predictions of chiral perturbation theory. These dispersion relations are based on specific forms for the absorptive part of…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Pasquini , D. Drechsel , S. Scherer

We show that the interplay of chiral effective field theory and lattice QCD can be used in the evaluation of so-called disconnected diagrams, which appear in the study of the isoscalar and isovector channels of pion-pion scattering and have…

High Energy Physics - Lattice · Physics 2017-12-22 Neramballi Ripunjay Acharya , Feng-Kun Guo , Ulf-G. Meißner , Chien-Yeah Seng

Chiral dynamics is a pretty mature field. Nonetheless, there are many exciting new developments. In this opening talk, I consider S-wave, isospin-zero pion-pion scattering and the calculation of the width of the lightest baryon resonances…

High Energy Physics - Phenomenology · Physics 2019-12-16 Ulf-G. Meißner

We apply chiral quark model with momentum dependent quark mass to two kinds of non-perturbative objects. These are: photon Distribution Amplitudes which we calculate up to twist-4 in tensor, vector and axial channels and pion-photon…

High Energy Physics - Phenomenology · Physics 2010-02-19 Piotr Kotko

We present and apply a novel scheme for studying photon- and pion-nucleon scattering beyond the threshold region. Partial-wave amplitudes for the $\gamma\, N$ and $\pi N$ states are obtained by an analytic extrapolation of subthreshold…

High Energy Physics - Phenomenology · Physics 2015-03-13 A. Gasparyan , M. F. M. Lutz

A brief discussion of the elastic pion-pion scattering amplitude to two loops in chiral perturbation theory is given. Some technical details of the evaluation of two-loop diagrams are addressed, and results relevant for the pionium decay…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. E. Sainio

The elastic pi-N scattering amplitude in the isospin limit is calculated in the framework of heavy baryon chiral perturbation theory, up to the third order. Threshold parameters like scattering lengths, volumes, effective ranges, etc. are…

High Energy Physics - Phenomenology · Physics 2011-09-13 Martin Mojzis

We have performed a systematical calculation of the pion ($\pi, K, \eta$) and heavy pseudoscalar meson S-wave scattering lengths up to ${\cal O}(p^3)$ in the chiral perturbation theory in the heavy quark symmetry limit. With the three…

High Energy Physics - Phenomenology · Physics 2009-07-30 Yan-Rui Liu , Xiang Liu , Shi-Lin Zhu

The central two-pion exchange NN potential at large distances is studied in the framework of relativistic chiral symmetry and related directly to the nucleon scalar form factor, which describes the mass density of its pion cloud. This…

Nuclear Theory · Physics 2009-11-06 M. R. Robilotta