相关论文: Chiral Perturbation Theory
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…
The use of the equations of motion and meson field redefinitions allows the development of a simplified resonance chiral theory lagrangian: terms including resonance fields and a large number of derivatives can be reduced into corresponding…
In these notes we present an introductory review on various topics about low energy pion physics (some kaon physics is discussed as well). Among these, we include the uses of analyticity and unitarity to describe partial wave amplitudes…
A short overview of theoretical predictions for various kaon decays is presented. Particular attention is devoted to pure and radiative nonleptonic decays in the framework of Chiral Perturbation Theory. The relevance of KLOE's future…
By applying chiral-perturbation-theory methods to the QCD sector of the Lorentz-violating Standard-Model Extension, we investigate Lorentz violation in the strong interactions. In particular, we consider the CPT-even pure-gluon operator of…
These lectures introduce some of the basic notions of effective field theories, as used in particle physics. The topics discussed are the $\Delta S=1$ and $\Delta S =2$ weak interactions, and chiral perturbation theory as applied to mesons,…
We apply the relativistic chiral Lagrangian to the nuclear equation of state. An effective chiral power expansion scheme, which is constructed to work around nuclear saturation density, is presented. The leading and subleading terms are…
Recent developments in calculations of low energy nucleon properties utilizing effective chiral field theories with explicit spin 3/2 matter fields are presented. In particular, the role of Delta resonances in microscopic calculations of…
The effects of an external field on the dynamics of chiral symmetry breaking are studied using quenched, ladder QED as our model gauge field theory. It is found that a uniform external magnetic field enables the chiral symmetry to be…
We present an accurate nucleon-nucleon (NN) potential based upon chiral effective Lagrangians. The model includes one- and two-pion exchange contributions up to chiral order three and contact terms (which represent the short range force) up…
A review of the modern theory of hadronic atoms based on the non-relativistic effective Lagrangian approach and ChPT, is given. As an application of the general framework, we consider the decay of the pi+pi- atom into two neutral pions, and…
Elastic pion-pion and pion-nucleon scattering are reviewed in the context of chiral perturbation theory. Theoretical results from systematic low-energy expansions to O(p^6) for pion-pion and to O(p^3) for pion-nucleon scattering are…
Chiral low-energy constants incorporate short-distance information from the dynamics involving heavier degrees of freedom not present in the chiral Lagrangian. We have studied the contribution of the lightest resonances to the chiral…
Spontaneous breaking of chiral symmetry in QCD has traditionally been inferred indirectly through low-energy theorems and comparison with experiments. Thanks to the understanding of an unexpected connection between chiral Random Matrix…
In the last century the non-perturbative regularization of chiral fermions was a long-standing problem. We review how this problem was finally overcome by the formulation of a modified but exact form of chiral symmetry on the lattice. This…
Chiral perturbation theory in the anomaly sector for $N_f=2$ is extended to include dynamical photons, thereby allowing a complete treatment of isospin breaking. A minimal set of independent chiral lagrangian terms is determined and the…
We study the electromagnetic form factors of a nucleon in next-to-leading order chiral perturbation theory (CPT) in the case where one of the nucleons is off its mass shell. We calculate the leading nonanalytic contributions to relevant…
Nuclear theory has entered an exciting era. This is due to advances on many fronts, including the development of effective field theory and the renormalization group for nuclear forces, advances in ab-initio methods for nuclear structure,…
A new geometrical interpretation of chiral perturbation theory based on topological QCD is presented in picture format. This work is a written summary of a talk given at NAPP 2003 in Dubrovnik, Croatia.
We use chiral perturbation theory to investigate hadronic properties in strong electric and magnetic fields. A strong-field power counting is employed, and results for pions and nucleons are obtained using Schwinger's proper-time method. In…