Related papers: The Two-Nucleon System beyond the Pion Threshold
The nucleon-nucleon problem is studied as a six-quark system in a nonrelativistic chiral constituent quark model where the Hamiltonian contains a linear confinement and a pseudoscalar meson (Goldstone boson) exchange interaction between the…
The application of the chiral effective theory to processes with two or more nucleons is discussed. We gain a qualitative understanding of the gross features of nuclear physics and quantitative, testable postdictions and predictions…
A selected set of topics along the borderline between perturbative and nonperturbative QCD in exclusive reactions are studied. Specific problems, related to different mechanisms of momentum transfer to an intact hadron, are discussed.…
We investigate the nucleon-nucleon interaction by using the meson exchange model and the two body Dirac equations of constraint dynamics. This approach to the two body problem has been successfully tested for QED and QCD relativistic bound…
It has been shown that CP violating electron-nucleon and nucleon-nucleon interactions can induce atomic electric dipole moments and are therefore constrained from experimental data. We show that using the experimental upper bounds on…
The double pion photoproduction off nucleons near threshold is analyzed in a covariant baryon chiral perturbation theory up to next to leading order, where the $\Delta(1232)$, $N^*(1400)$ and $\rho(770)$ resonances are included as explicit…
Photo- and electroproduction of pions and eta-mesons is studied on the nucleon. The formalism of such reactions is presented including polarization degrees of freedom and theoretical approaches are discussed. In particular, the threshold…
A model for the nucleon-antinucleon interaction is presented which is based on meson-baryon dynamics. The elastic part is the $G$-parity transform of the Bonn $NN$ potential. Annihilation into two mesons is described in terms of microscopic…
The recently developed semi-local improved chiral nucleon-nucleon interaction is used for the first time to study several electromagnetic and weak processes at energies below the pion production threshold. Cross sections and selected…
The current status of electric dipole moments of diamagnetic atoms which involves the synergy between atomic experiments and three different theoretical areas -- particle, nuclear and atomic is reviewed. Various models of particle physics…
Any possible Lorentz violation in the hadron sector must be tied to Lorentz violation at the underlying quark level. The relationships between the theories at these two levels are studied using chiral perturbation theory. Starting from a…
In the framework of chiral perturbation theory we investigate whether, in the presence of nucleons, a many-particle system may lower its energy density by changing its mesonic vacuum from a homogeneous to a spiral configuration. Numerical…
We derive the leading two-pion exchange contributions to the two-nucleon electromagnetic current operator in the framework of chiral effective field theory using the method of unitary transformation. Explicit results for the current and…
A newly-proposed parity-violating nucleon-nucleon interaction based on effective field theory is studied in this work. It is found that at low energy, i.e., E_lab less than 90 MeV for 1S0-3P0 transitions and E_lab less than 40 MeV for…
This work implements pionless effective field theory with the two-nucleon system expanded around the unitarity limit at second order perturbation theory. The expansion is found to converge well. All Coulomb effects are treated in…
We discuss selected and important features of hadronic molecules as one of promising forms of exotic hadrons near thresholds. Using examples of $D \bar D^*$ systems such as $X(3872)$ and $Z_c$, emphasis is put on the roles of the one pion…
Deepening our knowledge of the partonic content of nucleons and nuclei represents a central endeavour of modern high-energy and nuclear physics, with ramifications in related disciplines such as astroparticle physics. There are two main…
Several boson exchange potentials, describing the NN interaction $T_\ell\le 300$ MeV with high quality, are extended in their range of applicability as NN optical models with complex local or separable potentials in r-space or as complex…
Ultra-peripheral collisions of heavy ions and protons are the energy frontier for electromagnetic interactions. Both photonuclear and two-photon collisions are studied, at collision energies that are far higher than are available elsewhere.…
The hadronic light-by-light contribution to the anomalous magnetic moment of the muon was recently analyzed in the framework of dispersion theory, providing a systematic formalism where all input quantities are expressed in terms of…