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Related papers: Effective Field Theory Approach to Pionium

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We consider a pionless effective theory with dibaryon fields for the description of the weak process involving two nucleons. We construct leading order Lagrangians that contain nucleon-dibaryon weak coupling constants. We calculate the…

Nuclear Theory · Physics 2015-05-13 C. H. Hyun , J. W. Shin , S. Ando

In this work, dispersion relations of $\pi^0$ and $\pi^{\pm}$ have been studied in vacuum in the limit of weak external magnetic field using a phenomenological pion-nucleon $(\pi N)$ Lagrangian. For our purpose, we have calculated the…

Nuclear Theory · Physics 2016-05-04 Souvik Priyam Adhya , Mahatsab Mandal , Subhrajyoti Biswas , Pradip K. Roy

The subject of effective interactions is introduced and applications in both quantum mechanics and quantum field theory are presented. In particular the use of chiral perturbation theory as an effective low energy description of QCD is…

High Energy Physics - Phenomenology · Physics 2017-08-23 Barry R. Holstein

Two-point functions related to the pion weak decay constant f_\pi are calculated from the generating functional of chiral perturbation theory in the mean-field approximation and the heavy-baryon limit. The aim is to demonstrate that Lorentz…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mariana Kirchbach , Andreas Wirzba

Recently, we developed an effective theory of pions and a light dilatonic meson for gauge theories with spontaneously broken chiral symmetry that are close to the conformal window. The pion mass term in this effective theory depends on an…

High Energy Physics - Phenomenology · Physics 2017-02-01 Maarten Golterman , Yigal Shamir

In this talk, we review our recent calculation for the $pp\to pp\pi^0$ reaction near threshold in pionless effective field theory with a di-baryon and external pions.

Nuclear Theory · Physics 2009-07-16 Shung-ichi Ando

We point out a redundancy in the operator structure of the pionless effective field theory which dramatically simplifies computations. This redundancy is best exploited by using dibaryon fields as fundamental degrees of freedom. In turn,…

Nuclear Theory · Physics 2014-11-18 Silas R. Beane , Martin J. Savage

With the LHC entering the precision era, focus on interpreting the measurements performed in an effective field theory holds key to testing the Standard Model. An effective field theory provides a well-defined theoretical formalism which…

Data Analysis, Statistics and Probability · Physics 2024-03-27 Rahul Balasubramanian , Lydia Brenner , Carsten Burgard , Wouter Verkerke

A simple matching procedure is proposed to extract constraints on effective meson theories. In this way, a QCD prediction for the pion decay constant is found, F(pi)=2 m(pi)/pi, i.e. approximately 90MeV. The same procedure also determines…

High Energy Physics - Phenomenology · Physics 2007-05-23 Christopher Smith

We develop an effective field theory to describe the coupling of non-thermal quantum black holes to particles such as those of the Standard Model. The effective Lagrangian is determined by imposing that the production cross section of a…

High Energy Physics - Phenomenology · Physics 2015-05-28 Xavier Calmet , Dionysios Fragkakis , Nina Gausmann

Pion-nucleon scattering, pion photoproduction, and nucleon Compton scattering are analyzed within a scheme based on the chiral Lagrangian. Partial-wave amplitudes are obtained by an analytic extrapolation of subthreshold reaction amplitudes…

High Energy Physics - Phenomenology · Physics 2011-02-11 A. M. Gasparyan , M. F. M. Lutz

We extend the usual chiral perturbation theory framework ($\chi$PT) to allow the inclusion of a light dynamical isosinglet scalar. Using lattice QCD results, and a few phenomenological inputs, we explore the parameter space of the effective…

High Energy Physics - Phenomenology · Physics 2015-05-30 J. Soto , P. Talavera , J. Tarrús

We review the theory of hadronic atoms in QCD+QED. The non-relativistic effective Lagrangian approach, used to describe this type of bound states, is illustrated with the case of pi+pi- atoms. In addition, we discuss the evaluation of…

High Energy Physics - Phenomenology · Physics 2009-12-15 J. Gasser , V. E. Lyubovitskij , A. Rusetsky

The pionless effective field theory (EFT) is the appropriate low-energy EFT for short-range interactions that display a large scattering length. It has been successfully applied in atomic, nuclear and particle physics. We give an overview…

Nuclear Theory · Physics 2014-11-20 Lucas Platter

We calculate the nucleon-nucleon scattering amplitudes in the 1S0 and 3S1-3D1 channels at next-to-next to leading order starting from a recently proposed non-relativistic chiral effective theory, which includes dibaryon fields as…

Nuclear Theory · Physics 2010-04-06 Joan Soto , Jaume Tarrus

Progress in the Effective Field Theory of two and three nucleon systems is sketched, concentrating on the low energy version in which pions are integrated out as explicit degrees of freedom. Examples given are calculations of deuteron…

Nuclear Theory · Physics 2009-11-06 Harald W. Griesshammer

We reconsider the derivation of the nucleon-nucleon parity-violating (PV) potential within a chiral effective field theory framework. We construct the potential up to next-to-next-to-leading order by including one-pion-exchange,…

Nuclear Theory · Physics 2015-06-19 M. Viviani , A. Baroni , L. Girlanda , A. Kievsky , L. E. Marcucci , R. Schiavilla

We construct the Lagrangian for an effective theory of highly energetic quarks with energy Q, interacting with collinear and soft gluons. This theory has two low energy scales, the transverse momentum of the collinear particles, p_perp, and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Christian W. Bauer , Sean Fleming , Dan Pirjol , Iain W. Stewart

In a previous paper, the convergence of the effective field theory approach of Furnstahl, Serot and Tang to the nuclear many-body problem was studied by applying it to selected doubly-magic, and neighboring single-particle and single-hole,…

Nuclear Theory · Physics 2007-05-23 M. A. Huertas

The effective chiral Lagrangian of the strong and electromagnetic interactions of the pseudoscalar mesons at low energies depends on a set of low energy constants. We determine the contributions to the electromagnetic coupling constants at…

High Energy Physics - Phenomenology · Physics 2009-10-30 Robert Baur , Res Urech
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