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Related papers: Recent developments in chiral perturbation theory

200 papers

We study the difficulties associated with detecting chiral singularities predicted by chiral perturbation theory (ChPT) in lattice QCD. We focus on the physics of the remnant O(2) chiral symmetry of staggered fermions in the strong coupling…

High Energy Physics - Lattice · Physics 2016-09-01 Shailesh Chandrasekharan , Costas G. Strouthos

We consider chiral perturbation theory in the meson sector at order $E^6$. In the terminology of the external field technique, the two--loop graphs so generated are of the sunset type. We discuss the evaluation of several of these in the…

High Energy Physics - Phenomenology · Physics 2011-09-13 J. Gasser , M. E. Sainio

We evaluate the amplitude for $\gamma \gamma \rightarrow \pi^0 \pi^0$ to two loops in chiral perturbation theory. The three new counterterms which enter at this order in the low-energy expansion are estimated with resonance saturation. We…

High Energy Physics - Phenomenology · Physics 2011-07-19 S. Bellucci , J. Gasser , M. E. Sainio

Corrections to $K_{L}^{0}\rightarrow \pi^{0} \gamma \gamma$ decay induced by scalar meson exchange are studied within chiral perturbation theory. In spite of bad knowledge of scalar-mesons parameters, the calculated branching ratio can be…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Fajfer

This study presents a tree-level calculation of the scattering amplitude for the $lp\to lp\gamma$ (with a hard photon) process within the framework of Chiral Perturbation Theory. Our calculations, based on the $O(p^2)$ and $O(p^3)$…

High Energy Physics - Phenomenology · Physics 2026-02-13 Xu Wang , Kai-Ge Kang , Zhiguang Xiao , Han-Qing Zheng

The neutral Kaon decays Ks->gamma gamma and Kl->pi0 gamma gamma are very sensitive to higher order loop effects of Chiral Perturbation Theory (ChPT). New measurements of the NA48 experiment show that ChPT contributions of O(p^6) cannot be…

High Energy Physics - Experiment · Physics 2007-05-23 Rainer Wanke

We study the decay Omega^- -> Xi^- pi^+ pi^- in heavy-baryon chiral perturbation theory. At leading order, the decay is completely dominated by the Xi^{*0}(1530) intermediate state, and the predicted rate and Xi^-pi^+ mass distribution are…

High Energy Physics - Phenomenology · Physics 2008-11-26 Oleg Antipin , Jusak Tandean , G. Valencia

We highlight some of the recent advances in the application of chiral effective field theory (chiral EFT) with baryons to the $\pi N$ scattering process. We recall some problems that cast doubt on the applicability of chiral EFT to $\pi N$…

High Energy Physics - Phenomenology · Physics 2015-06-18 Jose Manuel Alarcón

The $\sigma$-terms are calculated at next-to-leading order in heavy baryon chiral perturbation theory by employing a cutoff regularization. The results do not depend on the cutoff value to the order we are working . The baryon masses and…

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

A phenomenological analysis of $K\to \pi\pi\gamma$ ($K_L\to\pi^+\pi^-\gamma$ and $K^+\to\pi^+\pi^0\gamma$) with the direct emission photon is carried out beyond the leading order in the chiral perturbation theory. We show that the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Giancarlo D'Ambrosio , Dao-Neng Gao

I summarize two recent applications of chiral perturbation theory to electromagnetic reactions on deuterium: elastic electron-deuteron scattering, and Compton scattering on deuterium. Both calculations have now been carried out to three…

Nuclear Theory · Physics 2009-11-11 Daniel R. Phillips

We incorporate heavy-light mesons into staggered chiral perturbation theory, working to leading order in 1/m_Q, where m_Q is the heavy quark mass. At first non-trivial order in the chiral expansion, staggered taste violations affect the…

High Energy Physics - Lattice · Physics 2009-11-11 C. Aubin , C. Bernard

We apply hard pion Chiral Perturbation Theory to charmonium decays to $\pi\pi$, $KK$ and $\eta\eta$. We first discuss why we expect to be able to provide results for the chiral logarithms in $\chi_{c0}$ and $\chi_{c2}$ decays to two…

High Energy Physics - Phenomenology · Physics 2015-05-30 Johan Bijnens , Ilaria Jemos

We study the |Delta I|=3/2 amplitudes of hyperon non-leptonic decays of the form B->B'+pi in the context of chiral perturbation theory. The lowest-order predictions are determined in terms of only one unknown parameter and are consistent…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Abd El-Hady , Jusak Tandean , G. Valencia

Quenched and partially quenched chiral perturbation theory for vector mesons is developed and is used to extract chiral loop correction to the $\rho$ meson mass. Connections to fully quenched and totally unquenched chiral perturbation…

High Energy Physics - Phenomenology · Physics 2009-10-30 Chi-Keung Chow , Soo-Jong Rey

In this paper we use one-loop chiral perturbation theory in order to compare lattice computations of the K+ to pi+ pi0 decay amplitude with the experimental value. This makes it possible to investigate three systematic effects that plague…

High Energy Physics - Lattice · Physics 2016-08-24 Maarten Golterman , Ka Chun Leung

A reanalysis of the radiative pion decay together with the calculation of the radiative corrections within chiral perturbation theory (CHPT) is performed. The amplitude of this decay contains an inner Bremsstrahlung contribution and a…

High Energy Physics - Phenomenology · Physics 2008-11-26 Rene Unterdorfer , Hannes Pichl

Heavy baryon chiral perturbation theory ($\chi$PT), where the $\Delta$ resonance is included, is used in order to examine the axial charged-current component of the weak interaction process at low neutrino energies. At leading chiral order…

Nuclear Theory · Physics 2019-03-13 Fred Myhrer

Third order chiral perturbation theory accounts for the $\pi-N$ scattering phase shift data out to energies slightly below the position of the $\Delta$ resonance. The low energy constants are not accurately determined. Explicit inclusion of…

Nuclear Theory · Physics 2017-08-23 P. J. Ellis

Chiral perturbation theory is nowadays a well-established approach to incorporate the chiral constraints from QCD. Nevertheless, for systems involving one baryon, the power counting which dictates the chiral order of observables is not as…

Nuclear Theory · Physics 2014-11-20 Renato Higa