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Superscaling properties of 12C, 16O and 40Ca nuclear responses, induced by electron and neutrino scattering, are studied for momentum transfer values between 300 and 700 MeV/c. We have defined two indexes to have quantitative estimates of…

Nuclear Theory · Physics 2008-11-26 M. Martini , G. Co' , M. Anguiano , A. M. Lallena

High-precision measurements in neutrino oscillation experiments require a very accurate description of the lepton-nucleus scattering process. Several cross-section calculations are available, but important discrepancies are still present…

Nuclear Theory · Physics 2024-01-12 Valerio Belocchi , Maria Benedetta Barbaro , Arturo De Pace , Marco Martini

Hadron properties are studied at hot medium using the quark sigma model. The quark sigma model is extended to include eighth-order of mesonic interactions based on some aspects of quantum chromodynamic (QCD) theory. The extended effective…

High Energy Physics - Phenomenology · Physics 2015-01-05 M. Abu-Shady , A. K. Abu-Nab

We calculate the nucleon resonance contributions to nucleon Compton scattering, including all states with J^P = 1/2^{+-} and J^P = 3/2^{+-} where experimental data for their electromagnetic transition form factors exist. To this end, we…

High Energy Physics - Phenomenology · Physics 2018-12-05 Gernot Eichmann , G. Ramalho

A recently developed model for $\rho$-meson propagation in dense hadronic matter is applied to total photoabsorption cross sections in $\gamma$-proton and $\gamma$-nucleus reactions. Within the vector dominance model the photon coupling to…

Nuclear Theory · Physics 2008-11-26 R. Rapp , M. Urban , M. Buballa , J. Wambach

We revisit the question of the contributions of two-photon exchange with $\Delta(1232)$ excitation to the electron-proton scattering in a hadronic model. Three improvements over the previous calculations are made, namely, correct vertex…

Nuclear Theory · Physics 2015-09-21 Hai-Qing Zhou , Shin Nan Yang

The structure of hadrons relevant for deep-inelastic scattering are completely characterised by the Compton amplitude. A direct calculation of the Compton amplitude in a lattice QCD setup provides a way to accessing the structure functions,…

Pion-nucleus bremsstrahlung offers a possibility of measuring the structure functions of pion-Compton scattering from a study of the small-momentum-transfer region where the bremsstrahlung reaction is dominated by the single-photon-exchange…

Nuclear Theory · Physics 2013-01-01 Göran Fäldt , Ulla Tengblad

A consistent analysis of relativistic pionic correlations and meson-exchange currents for electroweak quasielastic electron scattering from nuclei is carried out. Fully-relativistic one-pion-exchange electromagnetic operators are developed…

Nuclear Theory · Physics 2008-11-26 J. E. Amaro , M. B. Barbaro , J. A. Caballero , T. W. Donnelly , A. Molinari

The binding energy of nuclear matter including exchange and pionic effects is calculated in a quark-meson coupling model with massive constituent quarks. As in the case with elementary nucleons in QHD, exchange effects are repulsive.…

Nuclear Theory · Physics 2009-10-31 M. E. Bracco , G. Krein , M. Nielsen

Interpretation of current and future neutrino oscillation and electron scattering experiments requires knowledge of lepton-nucleon and lepton-nucleus interactions at the percent level. We study the exchange of photons between charged…

Nuclear Theory · Physics 2022-10-19 Oleksandr Tomalak , Ivan Vitev

In an effective Lagrangian model employing the K-matrix approximation we extract nucleon resonance parameters. To this end we analyze simultaneously all available data for reactions involving the final states $\pi N$, $\pi\pi N$, $\eta N$…

Nuclear Theory · Physics 2008-11-26 T. Feuster , U. Mosel

A microscopic model for the $N\bar N\to\pi\pi$ process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical information. The scalar ($\sigma$) and vector ($\rho$) piece of…

Nuclear Theory · Physics 2009-09-25 C. Schütz , J. W. Durso , K. Holinde , B. C. Pearce , J. Speth

A new non-relativistic expansion in terms of the nucleon's momentum inside nuclear matter of the current for isobar electro-excitation from the nucleon is performed. Being exact with respect to the transferred energy and momentum, this…

Nuclear Theory · Physics 2008-11-26 J. E. Amaro , M. B. Barbaro , J. A. Caballero , T. W. Donnelly , A. Molinari

We analyze the role of meson exchange currents (MEC) in photon- and electron-induced one nucleon emission reactions in a fully relativistic model. The relativistic mean field theory is used for the bound state and the Pauli reduction for…

Nuclear Theory · Physics 2009-11-07 Andrea Meucci , Carlotta Giusti , Franco Davide Pacati

An effective field theory is used to give a model-independent description of Compton scattering at energies comparable to the pion mass. The amplitudes for scattering on the proton and the deuteron, calculated to fourth order in small…

Nuclear Theory · Physics 2008-11-26 S. R. Beane , M. Malheiro , J. A. McGovern , D. R. Phillips , U. van Kolck

We present the dispersion relation approach based on unitarity and analyticity to evaluate the two-photon exchange contribution to elastic electron-proton scattering. The leading elastic and first inelastic $\pi N$ intermediate state…

High Energy Physics - Phenomenology · Physics 2018-07-04 Oleksandr Tomalak

Using relativistic Hartree-Fock (RHF) approximation, we study the effect of Fock terms on the nuclear properties not only around the saturation density, $\rho_{0}$, but also at higher densities. In particular, we investigate how the…

We review coherent scattering of neutrinos on nuclei by coupling the weak currents to vector and axial-vector meson states. The couplings are obtained from known reactions, like $\tau$--lepton and vector meson decays. We compute and present…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. A. Paschos , A. V. Kartavtsev

To understand spin interactions in materials of the Cu$_2$Sb structure type, inelastic neutron scattering of Fe$_2$As single crystals was examined at different temperatures and incident neutron energies. The experimental phonon spectra…