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We derive the long-range components of the nucleon-nucleon (NN) two-pion-exchange potential with an intermediate Roper resonance. Leading-order interactions in heavy-baryon chiral perturbation theory are considered. NN phase shifts with…

Nuclear Theory · Physics 2026-03-02 Yang Xiao , Li-Sheng Geng , U. van Kolck

Short range meson-exchange mechanisms such as $\rho\to\omega\pi^0$ contribute significantly to the amplitude for $pp\rightarrow pp\pi^0$ near threshold in addition to pion rescattering. The uncertainty of the latter contribution, which…

Nuclear Theory · Physics 2008-11-26 U. van Kolck , G. A. Miller , D. O. Riska

Spin-isospin response in exotic nuclear systems is investigated. It is found that in some nuclei excitations with pionic quantum numbers (0-, 1+, 2-, ...) appear at very low energies with large transition probabilities, which is an…

Nuclear Theory · Physics 2015-10-28 Elena Litvinova

Two-photon exchange contributions have potentially broad ranging impact on several charged lepton scattering measurements. Previously believed to be extremely small, based in part on comparisons of positron scattering and electron…

Nuclear Experiment · Physics 2015-05-13 John Arrington

We evaluate the quasielastic double differential neutrino cross sections obtained in a phenomenological model based on the superscaling behavior of electron scattering data. We compare our results with the recent experimental data for…

Nuclear Theory · Physics 2011-01-20 J. E. Amaro , M. B. Barbaro , J. A. Caballero , T. W. Donnelly , C. F. Williamson

We calculate in heavy baryon chiral perturbation theory the local NN-potentials generated by the two-pion exchange diagrams at two-loop order. We give explicit expressions for the mass-spectra (or imaginary parts) of the corresponding…

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

We evaluate quasielastic double-differential antineutrino cross sections obtained in a phenomenological model based on the superscaling behavior of electron scattering data and estimate the contribution of the vector meson-exchange currents…

Nuclear Theory · Physics 2013-05-30 J. E. Amaro , M. B. Barbaro , J. A. Caballero , T. W. Donnelly

We study the pp \to pp\pi^0 reaction near threshold based on heavy-baryon chiral perturbation theory. We show that the two-pion-exchange diagrams give much larger contribution than the one-pion-exchange diagram which is of lower chiral…

Nuclear Theory · Physics 2008-11-26 F. Myhrer

We analyze the many-particle correlations that affect the optical properties of two-dimensional semiconductors. These correlations manifest themselves through the specific optical resonances such as excitons, trions, etc. Starting from the…

Mesoscale and Nanoscale Physics · Physics 2021-03-24 A. Kudlis , I. Iorsh

We review some recent progress in the study of electroweak interactions in nuclei within the SuSAv2-MEC model. The model has the capability to predict (anti)neutrino scattering observables on different nuclei. The theoretical predictions…

We look at the new two-particle correlation function that can provide the space-time information about the source of two charged pions. This function clearly reflects the chaotic and incoherent nature of the particle emission source…

High Energy Physics - Phenomenology · Physics 2010-11-11 G. A. Kozlov

Using multi-particle distribution functions we calculate the correlations produced by a periodically driven scatterer in a system of noninteracting electrons at zero temperature. The multi-particle correlations due to a quantum exchange…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Moskalets , M. Buttiker

We present a detailed analysis of $e^+e^-\to\pi^+\pi^-$ data up to $\sqrt{s}=1\,\text{GeV}$ in the framework of dispersion relations. Starting from a family of $\pi\pi$ $P$-wave phase shifts, as derived from a previous Roy-equation analysis…

High Energy Physics - Phenomenology · Physics 2019-02-06 Gilberto Colangelo , Martin Hoferichter , Peter Stoffer

A dynamical model for S-- and P--wave correlated $2 \pi$ (and $K \bar K$) exchange between a kaon and a nucleon is presented, starting from corresponding $N \bar N \rightarrow K \bar K$ amplitudes in the pseudophysical region, which have…

Nuclear Theory · Physics 2009-10-28 M. Hoffmann , J. W. Durso , K. Holinde , B. C. Pearce , J. Speth

Nuclear corrections are presented for neutrino and electron induced reactions in a pedagogical manner. The formalism is demonstrated with numerical studies and is shown to produce substantial corrections in channels where the pions have the…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. A. Paschos , I. Schienbein , J. Y. Yu

We present our recent progress in the description of neutrino-nucleus interaction in the GeV region, of interest for ongoing and future oscillation experiments. In particular, we discuss the weak excitation of two-particle-two-hole states…

A dynamical coupled-channel model is presented for investigating the nucleon resonances in the meson production reactions induced by pions and photons. The model is based on an energy-independent Hamiltonian which is derived from a set of…

Nuclear Theory · Physics 2008-11-26 A. Matsuyama , T. Sato , T. -S. H. Lee

Modifications to the nucleon electric polarizability induced by pion and sigma exchange in the q-q potentials are studied by means of sum rule techniques within a non-relativistic quark model. Contributions from meson exchange interactions…

Nuclear Theory · Physics 2009-10-31 F. Cano , M. Traini

The contributions of short-range nucleon-nucleon (NN) correlations, various meson exchange current (MEC) terms and the influence of $\Delta$ isobar excitations (isobaric currents, IC) on exclusive two-nucleon knockout reactions induced by…

Nuclear Theory · Physics 2008-11-26 D. Knödler , H. Müther , P. Czerski

We reanalyze the scaling properties of inclusive quasielastic electron scattering from $^{12}$C by subtracting from the data the effects of two-particle emission. A model of relativistic meson-exchange currents (MEC) is employed within the…

Nuclear Theory · Physics 2021-08-11 V. L. Martinez-Consentino , I. Ruiz Simo , J. E. Amaro