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Related papers: Nuclear Interactions: The Chiral Picture

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The electromagnetic form factors of the nucleon are calculated in an extended chiral constituent-quark model where the effective interaction is described by the exchange of pseudoscalar, vector, and scalar mesons. Two-body current-density…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Demetriou , S. Boffi , M. Radici , R. F. Wagenbrunn

We optimize the nucleon-nucleon interaction from chiral effective field theory at next-to-next- to-leading order. The resulting new chiral force NNLOopt yields \chi^2 \approx 1 per degree of freedom for laboratory energies below…

The inclusive A(gamma,pi+ pi-)X reaction is studied theoretically. A sizeable enhancement of the cross section is found, in comparison with the scaling of the deuteron cross section (sigma_deuteron * A/2). This enhancement is due to the…

Nuclear Theory · Physics 2011-02-09 J. A. Gomez Tejedor , M. J. Vicente-Vacas , E. Oset

We derive a novel chiral power counting scheme for in-medium chiral perturbation theory with explicit nucleonic and pionic degrees of freedom coupled to external sources. It allows for a systematic expansion taking into account local as…

Nuclear Theory · Physics 2009-12-08 J. A. Oller , A. Lacour , U. -G. Meißner

Two-meson-exchange nucleon-nucleon potentials are derived where either one or both nucleons contains a pair vertex. Physically, the meson-pair vertices are meant to describe in an effective way (part of) the effects of heavy-meson exchange…

Nuclear Theory · Physics 2008-11-26 Th. A. Rijken , V. G. J. Stoks

We study the imaginary parts of the isoscalar electromagnetic and isovector axial form factors of the nucleon close to the $3\pi$-threshold in covariant baryon chiral perturbation theory. At the two-loop level, the contributions arising…

Nuclear Theory · Physics 2019-03-27 N. Kaiser , E. Passemar

We calculate at two-loop order in chiral perturbation theory the electromagnetic corrections to the dominant two-pion exchange nucleon-nucleon interaction that is generated by the isoscalar $\pi N$ contact-vertex proportional to the large…

Nuclear Theory · Physics 2008-11-26 N. Kaiser

We derive the parity- and time-reversal-violating nuclear interactions stemming from the QCD theta term and quark/gluon operators of effective dimension 6: quark electric dipole moments, quark and gluon chromo-electric dipole moments, and…

Nuclear Theory · Physics 2015-05-28 C. M. Maekawa , E. Mereghetti , J. de Vries , U. van Kolck

Chiral effective field theory has established itself as the method of choice to study nuclear forces and low-energy nuclear dynamics. I review the status and prospects of this approach and discuss ongoing efforts to advance the precision…

Nuclear Theory · Physics 2015-10-27 Evgeny Epelbaum

Charge-independence breaking due to the pion-mass difference in the (chiral) two-pion-exchange nucleon-nucleon force is investigated. A general argument based on symmetries is presented that relates the charge-symmetric part of that force…

Nuclear Theory · Physics 2014-11-18 J. L. Friar , U. van Kolck

Production of p-wave pions in nucleon-nucleon collisions is studied according to an improved power counting that embodies the constraints of chiral symmetry. Contributions from the first two non-vanishing orders are calculated. We find…

Nuclear Theory · Physics 2008-11-26 C. Hanhart , U. van Kolck , G. A. Miller

Nearly a recent century of work is divided to Nucleon-Nucleon (NN) interaction issue. We review some overall perspectives of NN interaction with a brief discussion about deuteron, general structure and symmetries of NN Lagrangian as well as…

Nuclear Theory · Physics 2014-08-29 M. Naghdi

The 1S0 pairing gap in isospin-symmetric nuclear matter and finite nuclei is investigated using the chiral nucleon-nucleon potential at the N3LO order in the two-body sector, and the N2LO order in the three-body sector. To include realistic…

Nuclear Theory · Physics 2013-05-30 Paolo Finelli , Tamara Niksic , Dario Vretenar

We calculate in baryon chiral perturbation theory the relativistic $1/M^2$-corrections to the leading order two-pion exchange diagrams. We give explicit expressions for the corresponding one-loop NN-amplitudes in momentum space. The…

Nuclear Theory · Physics 2009-11-07 N. Kaiser

We consider chiral perturbation theory with an explicit broad $\sigma$-meson and study its contribution to the scalar form factors of the pion and the nucleon. Our goal is to learn more about resonance saturation in the scalar sector.

High Energy Physics - Phenomenology · Physics 2019-10-30 Y. Ünal , Ulf-G. Meißner

We derive density-dependent corrections to the in-medium nucleon-nucleon interaction from the leading-order chiral three-nucleon force. To this order there are six distinct one-loop diagrams contributing to the in-medium nucleon-nucleon…

Nuclear Theory · Physics 2010-04-06 J. W. Holt , N. Kaiser , W. Weise

We present the expansion of the two-pion exchange three-nucleon potential (TPE-3NP) to chiral order q^4, which corresponds to a subset of all possibilities at this order and is based on the \piN amplitude at O(q^3). Results encompass both…

Nuclear Theory · Physics 2008-11-26 S. Ishikawa , M. R. Robilotta

Three-nucleon forces (3NFs), and in particular terms of the Fujita-Miyazawa type, strongly influence the structure of neutron-rich exotic isotopes. Ab-initio calculations have shown that chiral two- and three-nucleon interactions correctly…

Nuclear Theory · Physics 2014-08-20 V. Somà , A. Cipollone , C. Barbieri , P. Navrátil , T. Duguet

The charge-dependent nucleon-nucleon ($NN$) interactions are crucial in understanding the nuclear structure and reaction problems. This work explores the charge-dependent $NN$ interaction in covariant chiral effective field theory. By…

Nuclear Theory · Physics 2025-04-23 Yang Xiao , Jun-Xu Lu , Li-Sheng Geng

An improved density-matrix expansion is used to calculate the nuclear energy density functional from chiral two- and three-nucleon interactions. The two-body interaction comprises long-range one- and two-pion exchange contributions and a…

Nuclear Theory · Physics 2015-05-30 J. W. Holt , N. Kaiser , W. Weise