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Related papers: Effective Field Theory Approach to Pionium

200 papers

Nonrelativstic effective field theories have shown to be a useful framework to describe systems of weakly bound particles. This work focuses on the matching procedure to the underlying relativistic theory. The concept of a physical mass in…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Gall

Chiral perturbation theory, the low energy effective theory of the strong interactions for the light pseudoscalar degrees of freedom, is based on effective Lagrangian techniques and is an expansion in the powers of the external momenta and…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Ananthanarayan , P. Büttiker

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…

Nuclear Theory · Physics 2007-05-23 Matthias Lutz

This is a revised version of a talk given at the Chiral Dynamics Workshop at M.I.T., July 25, 1994. It reports results in three areas: (1) The isospin-violating interactions between one non-relativistic nucleon and any number of soft pions…

High Energy Physics - Phenomenology · Physics 2009-10-28 Steven Weinberg

We apply the formalism of Chiral Perturbation Theory out of thermal equilibrium to describe explosive production of pions via the parametric resonance mechanism. To lowest order the lagrangian is that of the Nonlinear Sigma Model where the…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Gomez Nicola

Effective field theories encode the predictions of a quantum field theory at low energy. The effective theory has a fairly low ultraviolet cutoff. As a result, loop corrections are small, at least if the effective action contains a term…

High Energy Physics - Lattice · Physics 2015-06-25 G. Mack , T. Kalkreuter , G. Palma , M. Speh

Using our present knowledge on effective hadronic theories, short-distance QCD information, the $1/N_C$ expansion, analyticity and unitarity, we derive an expression for the pion form factor, in terms of $m_\pi, m_K, M_\rho$ and $f_\pi$.…

High Energy Physics - Phenomenology · Physics 2011-05-05 F. Guerrero , A. Pich

Non equilibrium effective field theory is presented as an inhomogeneous field theory, using a formulation which is analogous to that of a gauge theory. This formulation underlines the importance of structural aspects of non-equilibrium,…

High Energy Physics - Theory · Physics 2007-05-23 Mark Burgess

We analyze new physics contributions to $e^+e^-\to W^+W^-$ at the TeV energy scale, employing an effective field theory framework. A complete basis of next-to-leading order operators in the standard model effective Lagrangian is used, both…

High Energy Physics - Phenomenology · Physics 2015-06-15 G. Buchalla , O. Cata , R. Rahn , M. Schlaffer

The leading non-Coulombic electromagnetic contributions to pi pi s-wave scattering lengths are computed in Chiral Perturbation Theory. It is shown that these corrections are zeroth order in the chiral expansion and associated with…

Nuclear Theory · Physics 2008-11-26 K. Maltman , C. E. Wolfe

For large values of the Higgs mass the low energy structure of the gauged linear sigma model in the spontaneously broken phase can adequately be described by an effective field theory. We present a manifestly gauge-invariant functional…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Nyffeler , A. Schenk

The LHC has confirmed the existence of a mass gap between the known particles and possible new states. Effective field theory is then the appropriate tool to search for low-energy signals of physics beyond the Standard Model. We adopt the…

High Energy Physics - Phenomenology · Physics 2020-09-07 Antonio Pich , Ignasi Rosell , Juan José Sanz-Cillero

Effective Lagrangians are a useful tool for a data-driven approach to physics beyond the Standard Model at the LHC. However, for the new physics scales accessible at the LHC, the effective operator expansion is only relatively slowly…

High Energy Physics - Phenomenology · Physics 2016-11-09 Ayres Freitas , David Lopez-Val , Tilman Plehn

We discuss a role of dibaryon fields in an effective field theory to study pion cloud effect around the unitary limit of two nucleon systems at low energies.

Nuclear Theory · Physics 2015-07-21 Shung-Ichi Ando

We study in various chiral models the pion charge radius, $\pi_{e3}$ form factor ratio, $\pi^\circ \to \gamma \gamma$ amplitude, charge pion polarizabilities, $\gamma\gamma \to \pi^\circ \pi^\circ$ amplitude at low energies and the $\pi\pi$…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. D. Scadron

We use an effective field theory (EFT) which contains only short-range interactions to study the dependence of a variety of three-nucleon observables on the pion mass. The pion-mass dependence of input quantities in our ``pionless'' EFT is…

Nuclear Theory · Physics 2008-11-26 H. -W. Hammer , D. R. Phillips , L. Platter

We derive the leading one-loop contribution to the one-pion exchange and short-range two-nucleon electromagnetic current operator in the framework of chiral effective field theory. The derivation is carried out using the method of unitary…

Nuclear Theory · Physics 2013-05-29 S. Koelling , E. Epelbaum , H. Krebs , U. -G. Meißner

We discuss the construction of the two-flavour axion-pion effective Lagrangian at the next-to-leading order (NLO) in chiral perturbation theory and present, as a phenomenological application, the calculation of the decay rate of a GeV-scale…

High Energy Physics - Phenomenology · Physics 2023-04-19 Luca Di Luzio , Gioacchino Piazza

Effective field theory techniques are used to describe the interaction of heavy hadrons in a model independent way. Predictability is obtained by exploiting the symmetries of QCD. Heavy hadron chiral perturbation theory is reviewed and used…

High Energy Physics - Phenomenology · Physics 2007-05-23 Iain W. Stewart

We show that for any effective field theory of colorless meson fields, the mixing schemes of particle states and decay constants are not only related but also determined exclusively by the kinetic and mass Lagrangian densities. In the…

High Energy Physics - Phenomenology · Physics 2009-11-07 E. Gedalin , A. Moalem , L. Razdolskaya