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Related papers: Chiral Perturbation Theory Beyond One Loop

200 papers

Partially quenched theories are theories in which the valence- and sea-quark masses are different. In this paper we calculate the nonanalytic one-loop corrections of some physical quantities: the chiral condensate, weak decay constants,…

High Energy Physics - Lattice · Physics 2008-11-26 Maarten Golterman , Ka Chun Leung

We give a brief introduction to chiral perturbation theory in its various settings. We discuss some applications of recent interest including chiral extrapolations for lattice gauge theory.

High Energy Physics - Phenomenology · Physics 2008-11-26 Véronique Bernard , Ulf-G. Meißner

I present an outline of chiral perturbation theory and discuss some recent developments in the field.

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Gasser

We apply Chiral Perturbation Theory at one loop to analyze the general formula for the pi+pi- atom lifetime derived recently in the framework of QCD. The corresponding analytic expression is investigated numerically, and compared with…

High Energy Physics - Phenomenology · Physics 2015-06-25 J. Gasser , V. E. Lyubovitskij , A. Rusetsky

I consider some selected topics in chiral perturbation theory (CHPT) as probed at colliders such as DA$\Phi$NE. Emphasis is put on processes involving pions in the isospin zero S-wave which require multi-loop calculations. These include the…

High Energy Physics - Phenomenology · Physics 2009-09-25 Ulf-G. Meißner

A short overview of the current state of Chiral Perturbation Theory is given. This includes a description of the basic assumptions, the usefulness of the external field method is emphasized using a simple lowest order example. Then at…

High Energy Physics - Phenomenology · Physics 2016-09-01 Johan Bijnens

Based on the external perturbation that disturbs the system only slightly from its equilibrium position we make the Taylor expansion of the pressure of a quark gas. It turns out that the first term was used in the literature to construct a…

High Energy Physics - Phenomenology · Physics 2011-09-19 Najmul Haque , Munshi G. Mustafa

A review of chiral perturbation theory and that of recent developments on the comparison of its predictions with experiment is presented. Some interesting topics with scope for further elaboration are touched upon.

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Ananthanarayan

I review some basic facts about the chiral limit of QCD. This allows to formulate an effective field theory below the chiral symmetry breaking scale, chiral perturbation theory (CHPT). I show that for threshold reactions, the spectrum of…

High Energy Physics - Phenomenology · Physics 2008-02-03 Ulf-G. Meißner

We present the results of the first two-loop calculation of a form factor in full $SU(3) \times SU(3)$ Chiral Perturbation Theory. We choose a specific linear combination of $\pi^+, K^+, K^0$ and $K\pi$ form factors (the one appearing in…

High Energy Physics - Phenomenology · Physics 2009-10-30 P. Post , K. Schilcher

I : Chiral Perturbation Theory is introduced and its applications to semileptonic and nonleptonic kaon decays are discussed. II: The method of large $N_c$ is used to calculate $K\to\pi\pi$ nonleptonic matrix elements, in particular the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Bijnens

We investigate electromagnetic effects in the framework of chiral perturbation theory. Using a completely independent method, we confirm Urech's results for the divergences of the one--loop functional in the electromagnetic sector. We…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. Neufeld , H. Rupertsberger

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

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

I describe recent developments in quenched chiral perturbation theory (QChPT) and the status of weak matrix elements involving light quarks. I illustrate how, with improved statistical errors, and with calculations of the masses of baryons…

High Energy Physics - Lattice · Physics 2009-10-28 Stephen R. Sharpe

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

Chiral symmetry breaking may exhibit significantly different patterns in two chiral limits: N_f=2 massless flavours (m_u=m_d=0, m_s physical) and N_f=3 massless flavours (m_u=m_d=0=m_s=0). Such a difference may arise due to vacuum…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Descotes-Genon

In this work, higher-derivative corrections of the non-linear sigma model of both even and odd intrinsic-parity sectors are systematically studied, focusing on ordered amplitudes of flavor scalars in massless limit. It should correspond to…

High Energy Physics - Theory · Physics 2022-01-05 Karol Kampf

We develop Chiral Perturbation Theory for chirally broken theories with fermions in two different representations of the gauge group. Any such theory has a non-anomalous singlet $U(1)_A$ symmetry, yielding an additional Nambu-Goldstone…

High Energy Physics - Phenomenology · Physics 2016-07-13 Thomas DeGrand , Maarten Golterman , Ethan T. Neil , Yigal Shamir

We evaluate the pion mass in finite volume to two loops within Chiral Perturbation Theory. The results are compared with a recently proposed extension of the asymptotic formula of Luscher. We find that contributions, which were neglected in…

High Energy Physics - Lattice · Physics 2007-05-23 Christoph Haefeli