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Related papers: Pion-photon exchange nucleon-nucleon potentials

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We have constructed a heavy baryon effective field theory with photon as an external field in accordance with the symmetry requirements similar to the heavy quark effective field theory. By treating the heavy baryon and anti-baryon equally…

High Energy Physics - Phenomenology · Physics 2014-11-18 K. B. Vijaya Kumar , Yong-Liang Ma , Yue-Liang Wu

We present a calculation of the fourth-order (NLO) contribution to spin-dependent forward Compton scattering in heavy-baryon chiral perturbation theory. No low-energy constants, except for the anomalous magnetic moments of the nucleon,…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. B. Vijaya Kumar , Judith A. McGovern , Michael C. Birse

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

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

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

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

Results for the antinucleon-nucleon ($\bar NN$) interaction obtained at next-to-next-to-next-to-leading order in chiral effective field theory (EFT) are reported. A new local regularization scheme is used for the pion-exchange contributions…

Nuclear Theory · Physics 2017-08-02 Ling-Yun Dai , Johann Haidenbauer , Ulf-G. Meißner

CERN COMPASS plans measurements of gamma-pi and gamma-K interactions using 50-280 GeV pion (kaon) beams and a virtual photon target. Pion (kaon) polarizabilities and radiative transitions will be measured via Primakoff effect reactions such…

High Energy Physics - Experiment · Physics 2009-10-31 Murray A. Moinester , Victor Steiner

We generalize the sum rules for the nucleon electric plus magnetic polarizability $\Sigma=\alpha+\beta$ and for the nucleon spin-polarizability $\gamma$, to virtual photons with $Q^2>0$. The dominant low energy cross sections are…

Nuclear Theory · Physics 2009-10-31 J. Edelmann , N. Kaiser , G. Piller , W. Weise

The evolution of nuclear shell structure is investigated for the first time within density-dependent relativistic Hartree-Fock theory and the role of $\pi$-exchange potential is studied in detail. The energy differences between the neutron…

Nuclear Theory · Physics 2008-11-26 Wen Hui Long , Hiroyuki Sagawa , Jie Meng , Nguyen Van Giai

We study the nucleon-nucleon interaction in the isoscalar-scalar channel using t he chiral unitary approach. The $t$-matrix of the pion-pion scattering in this c hannel is summed up to all orders using the B-S equation. We find that the…

Nuclear Theory · Physics 2009-11-06 E. Oset , H. Toki , M. Mizobe , T. T. Takahashi

In this work, we present an updated model for nuclear $\pi^0$ photoproduction, which incorporates pion second-order rescattering on intermediate excited nuclear states. Our approach is based on the distorted wave impulse approximation in…

Nuclear Theory · Physics 2024-08-01 Viacheslav Tsaran , Marc Vanderhaeghen

The two photon decay width of the neutral pion is analyzed within the combined framework of Chiral Perturbation Theory and the 1/Nc expansion up to order p^6 and p^4 times 1/Nc in the decay amplitude. The eta' is explicitly included in the…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. L. Goity , A. M. Bernstein , B. R. Holstein

The leading-order nucleon-nucleon (NN) potential derived from chiral perturbation theory consists of one-pion exchange plus a short-distance contact interaction. We show that in the 1S0 and 3S1-3D1 channels renormalization of the…

Nuclear Theory · Physics 2008-11-26 C. -J. Yang , Ch. Elster , D. R. Phillips

A forward dispersion calculation is implemented for the spin polarizabilities $\gamma_1, ... ,\gamma_4$ of the proton and the neutron. These polarizabilities are related to the spin structure of the nucleon at low energies and are…

Nuclear Theory · Physics 2009-10-30 D. Drechsel , G. Krein , O. Hanstein

The method of unitary transformations generates five classes of leading-order reducible chiral four-nucleon interactions which involve pion-exchanges and a spin-spin contact-term. Their first-order contributions to the energy per particle…

Nuclear Theory · Physics 2016-02-17 N. Kaiser , R. Milkus

We study interaction between two magnetic impurities on top of a two dimensional insulator in the presence of chiral phonons by second-order perturbation theory. We show that this exchange interaction arises from angular momentum of phonons…

Mesoscale and Nanoscale Physics · Physics 2025-10-13 Takehito Yokoyama

The spin and isospin structure of the amplitudes and observables for K+Lambda production in nucleon-nucleon collisions in the near-threshold region is analysed. It is shown that, with reasonable values for the relative strengths of the pi…

Nuclear Theory · Physics 2009-11-10 Goran Faldt , Colin Wilkin

We study the two-nucleon force at next-to-next-to-leading order in a chiral effective field theory with explicit Delta degrees of freedom. Fixing the appearing low-energy constants from a next-to-leading order calculation of pion-nucleon…

Nuclear Theory · Physics 2008-11-26 Hermann Krebs , Evgeny Epelbaum , Ulf-G. Meißner

In this work we consider the renormalization of the chiral two-pion exchange potential with explicit delta-excitations for nucleon-nucleon scattering at next-to-leading (NLO) and next-to-next-to-leading order (N2LO). Due to the singular…

Nuclear Theory · Physics 2015-03-17 M. Pavon Valderrama , E. Ruiz Arriola

The recently derived long-range two-pion exchange (TPE) contributions to the nuclear current operator which appear at next-to-leading order (NLO) of the chiral expansion are used to describe electromagnetic processes. We study their role in…

Nuclear Theory · Physics 2011-08-03 D. Rozpedzik , J. Golak , S. Kolling , E. Epelbaum , R. Skibinski , H. Witala , H. Krebs