相关论文: Charge-Symmetry Violation in Pion Scattering from …
We discuss the theoretical and experimental situations for charge symmetry violation (CSV) effects in the elastic scattering of pi+ and pi- on deuterium (D) and 3He/3H. Accurate comparison of data for both types of targets provides evidence…
We examine the scattering of charged pions from the trinucleon system at a pion energy of 180 MeV. The motivation for this study is the structure seen in the experimental angular distribution of back-angle scattering for pi+ 3He and pi- 3H…
Elastic nucleon scattering from the 3He and 3H mirror nuclei is examined as a test of charge symmetry violation. The differential cross-sections are calculated at 500 MeV using a microsopic, momentum-space optical potential including the…
Chiral effective field theory predicts a charge symmetry violating (CSB) amplitude for pion-nucleon scattering. This mechanism provides a very large contribution also to the CSB forward-backward asymmetry in the angular distribution of the…
We investigate three models for the charge symmetry breaking (CSB) of the nucleon-nucleon ($NN$) interaction (based upon $\rho$-$\omega$ mixing, nucleon mass splitting, and phenomenology) that all reproduce the empirical value for the CSB…
We construct density dependent Class $III$ charge symmetry violating (CSV) potential due to mixing of $\pi$-$\eta$ meson with off-shell corrections. The density dependence enters through the non-vanishing $\pi$-$\eta$ mixing driven by both…
The modification of the Paschos-Wolfenstein relation is investigated when the charge symmetry violations of valence and sea quark distributions in the nucleon are taken into account. We also study qualitatively the impact of charge symmetry…
In principle one can test the validity of charge symmetry for parton distributions by comparing structure functions measured in neutrino and charged lepton deep inelastic scattering. New experiments make such tests possible; they provide…
By comparing structure functions measured in neutrino and charged lepton deep inelastic scattering, one can test the validity of parton charge symmetry. New experiments allow us to make such tests, which set rather tight upper limits on…
Pion-nucleus elastic scattering at energies above the Delta(1232) resonance is studied using both pi+ and pi- beams on 12C, 40Ca, 90Zr, and 208Pb. The present data provide an opportunity to study the interaction of pions with nuclei at…
The longitudinal asymmetry induced by parity-violating (PV) components in the nucleon-nucleon potential is studied in the charge-exchange reaction 3He(n,p)3H at vanishing incident neutron energies. An expression for the PV observable is…
We investigate isospin breaking in low-energy pion-nucleon scattering in the framework of chiral perturbation theory. This work extends the systematic analysis of [1] to the energy range above threshold. Various relations, which identically…
Recent analyses of low-energy pion-nucleon experimental data have provided clear evidence for the violation of the isospin symmetry of the strong interaction. In the present work, it is shown that the single-charge-exchange reaction is the…
Based upon the Bonn meson-exchange model for the nucleon-nucleon ($NN$) interaction, we study systematically the charge-symmetry-breaking (CSB) of the $NN$ interaction due to nucleon mass splitting. Particular attention is payed to CSB…
We compute isospin-violating meson-nucleon coupling constants and their consequent charge-symmetry-breaking nucleon-nucleon potentials. The couplings result from evaluating matrix elements of quark currents between nucleon states in a…
We calculate isospin breaking in pion-nucleon scattering in the threshold region in the framework of covariant baryon chiral perturbation theory. All effects due to quark mass differences as well as real and virtual photons are consistently…
We construct the charge symmetry violating (CSV) nucleon-nucleon potential induced by the $\rho^0$-$\o$ mixing due to the neutron-proton mass difference driven by the $NN$ loop. Analytical expression for for the two-body CSV potential is…
We examine the effect of isospin-violating meson-nucleon coupling constants on low-energy pion-nucleon scattering. We compute the couplings in the context of a nonrelativistic quark model. The difference between the up and down constituent…
The basic facts of charge symmetry breaking (CSB) phenomena are reviewed. The relevance of CSB to parity-violating electron-proton scattering experiments that seek to extract strange elastic form factors is discussed. Experimentalists have…
Charge symmetry breaking (CSB) observables are a suitable experimental tool to examine effects induced by quark masses on the nuclear level. Previous high precision data from TRIUMF and IUCF are currently used to develop a consistent…