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Related papers: Topics in Chiral Perturbation Theory

200 papers

The differential cross sections and s-wave and p-wave multipoles for $\pi^- p \to \gamma n$ and $\pi^+ n \to \gamma p$ have been calculated through $O(p^3)$ in heavy baryon chiral perturbation theory (HBChPT). Fits to existing data allow…

High Energy Physics - Phenomenology · Physics 2009-10-31 Harold W. Fearing , Thomas R. Hemmert , Randy Lewis , Christine Unkmeir

We investigate isospin breaking in low-energy pion-nucleon scattering in the framework of chiral perturbation theory. This work extends the systematic analysis of [1] to the energy range above threshold. Various relations, which identically…

High Energy Physics - Phenomenology · Physics 2009-10-31 Nadia Fettes , Ulf-G. Meißner

Chiral symmetry and heavy quark symmetry constrain the interactions of mesons containing a single heavy quark with low-momentum pions. Chiral corrections to the Isgur-Wise function for $\bar B_s \rightarrow D_s^{(*)}$ versus $\bar B…

High Energy Physics - Phenomenology · Physics 2009-09-25 Elizabeth Jenkins

The total cross section for the pp --> pp $\pi^0$ reaction at energies close to threshold is calculated within the frame of a chiral perturbation theory. The tree and one loop diagrams up to chiral order D=2 contributions are taken into…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Gedalin , A. Moalem. L. Razdolskaya

The basic ideas and methods of chiral perturbation theory are briefly reviewed. I discuss the recent attempts to build an effective Lagrangian in the resonance region and summarize the known large-N_C constraints on the low-energy chiral…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. Pich

I discuss low-energy pion-nucleon scattering in the framework of chiral perturbation theory. I argue that using this theoretical method one is able to handle the in some cases tremendous experimental accuracy (for the low partial waves). I…

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

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 2014-11-20 B. Pasquini , D. Drechsel , S. Scherer

Heavy-baryon chiral perturbation theory (ChPT) at one loop fails in relating the pion-nucleon amplitude in the physical region and for subthreshold kinematics due to loop effects enhanced by large low-energy constants. Studying the chiral…

Nuclear Theory · Physics 2017-05-01 D. Siemens , J. Ruiz de Elvira , E. Epelbaum , M. Hoferichter , H. Krebs , B. Kubis , U. -G. Meißner

The non-leptonic hyperon decays are analyzed up to one-loop order including all counterterms in the framework of heavy baryon chiral perturbation theory. We use the exchange of the spin-3/2 decuplet resonances as an indication of which…

High Energy Physics - Phenomenology · Physics 2011-09-13 B. Borasoy , B. R. Holstein

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…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. J. Yndurain

We study the S-wave interaction of mesons with baryons in the strangeness S=0 sector in a coupled channel unitary approach. The basic dynamics is drawn from the lowest order meson baryon chiral Lagrangians. Small modifications inspired by…

High Energy Physics - Phenomenology · Physics 2011-02-09 T. Inoue , J. C. Nacher , M. J. Vicente Vacas , E. Oset

We consider pion-nucleon scattering in heavy-baryon chiral perturbation theory to third order. All electromagnetic corrections appearing to this order are included. We thus have a consistent description of strong and electromagnetic…

High Energy Physics - Phenomenology · Physics 2009-11-07 Nadia Fettes , Ulf-G. Meißner

We analyze various aspects of pion and kaon condensation in the framework of chiral perturbation theory. Considering a system at vanishing temperature and varying the isospin chemical potential and the strange quark chemical potential we…

High Energy Physics - Phenomenology · Physics 2015-10-21 Andrea Mammarella , Massimo Mannarelli

We present our predictions for meson form factors for the SU(3) octet and investigate their impact on the pion electroproduction cross sections. The electric and magnetic polarizabilities of the SU(3) octet of mesons and baryons are…

High Energy Physics - Phenomenology · Physics 2015-06-17 A. Aleksejevs , S. Barkanova

We consider chiral perturbation theory (ChPT) with a non-zero theta term. Due to the CP violating term, the vacuum of chiral fields is shifted to a non-trivial element on the SU(N_f) group manifold. The CP violation also provides mixing of…

High Energy Physics - Lattice · Physics 2014-11-20 Sinya Aoki , Hidenori Fukaya

Heavy baryon chiral perturbation theory including spin 3/2 delta resonances as effective degrees of freedom is reviewed. The theory admits a systematic expansion in the small scale $\epsilon$, where $\epsilon$ collectively denotes soft…

High Energy Physics - Phenomenology · Physics 2009-10-30 Joachim Kambor

We extend our previous analysis of the unitarized pion-nucleon scattering amplitude including up to fourth order terms in Heavy Baryon Chiral Perturbation Theory. We pay special attention to the stability of the generated Delta(1232…

Nuclear Theory · Physics 2009-11-10 A. Gomez Nicola , J. Nieves , J. R. Pelaez , E. Ruiz Arriola

The status of chiral perturbation theory in the meson sector is illustrated with several topical examples. The longtime discrepancy between theory and experiment for the charged pion polarizabilities has now been resolved in favour of the…

High Energy Physics - Phenomenology · Physics 2015-10-07 Gerhard Ecker

An overview of Chiral Perturbation Theory calculations in the mesonic sector at the two Loop level is given. Discussed in some detail are the partially quenched case relevant for lattice QCD, the general fitting procedures and $\pi\pi$,$\pi…

High Energy Physics - Phenomenology · Physics 2009-11-10 Johan Bijnens

We complete the analysis of twist-two generalized parton distributions of the nucleon in one-loop order of heavy-baryon chiral perturbation theory. Extending our previous study of the chiral-even isosinglet sector, we give results for…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Diehl , A. Manashov , A. Schafer