Related papers: The $\eta NN$-system at low energy within a three-…
A model calculation for pion production in nucleon-nucleon collisions is presented. Direct production, pion rescattering and contributions from pair diagrams are taken into account. The amplitudes for the elementary processes are based on…
This work presents further analysis of the three- and four-neutron systems in the low energy regime using adiabatic hyperspherical methods. In our previous Phys. Rev. Lett. article (Phys. Rev. Lett. 125, 052501 (2020)), the low-energy…
We calculate the renormalized effective 2-, 3-, and 4-body interactions for N neutral ultracold bosons in the ground state of an isotropic harmonic trap, assuming 2-body interactions modeled with the combination of a zero-range and…
We construct accurate models of three-nucleon (3N) interaction by fitting, in a hybrid phenomenological approach, the low-energy constants parametrizing the subleading 3N contact operators to the triton binding energy, n-d scattering…
Precise data for quasi-free photoproduction of $\eta$ mesons off the deuteron have been measured at the Bonn ELSA accelerator with the combined Crystal Barrel/TAPS detector for incident photon energies up to 2.5 GeV. The $\eta$-mesons have…
The electromagnetic interactions of a relativistic two-body bound state are formulated in three dimensions using an equal-time (ET) formalism. This involves a systematic reduction of four-dimensional dynamics to a three-dimensional form by…
We have done a theoretical study of the $\gamma d \to \pi^0 \eta d$ reaction starting with a realistic model for the $\gamma N \to \pi^0 \eta N$ reaction that reproduces cross sections and polarization observables at low energies and…
The cross sections for low-energy neutrino-deuteron reactions are calculated within heavy-baryon chiral perturbation theory employing cut-off regularization scheme. The transition operators are derived up to next-to-next-to-next-to-leading…
A chiral quark model approach is extended to the study of the $\pi N$ scattering at low energies. The process of $\pi^{-}p \to \eta n$ near threshold is investigated. The model is successful in describing the differential cross sections and…
A nuclear model is proposed where the nucleons interact by emitting and absorbing mesons, and where the mesons are treated explicitly. A nucleus in this model finds itself in a quantum superposition of states with different number of…
We discuss renormalization of the non-relativistic three-body problem with short-range forces. The problem is non-perturbative at momenta of the order of the inverse of the two-body scattering length. An infinite number of graphs must be…
Three- and four-nucleon photodisintegration processes are quite efficiently treated by means of effective two-body integral equations in momentum space. We recall some aspects of their derivation, present previous and most recent results…
Background: Phase-equivalent transformations (PETs) are well-known in quantum scattering and inverse scattering theory. PETs do not affect scattering phase shifts and bound state energies of two-body system but are conventionally supposed…
We study the lepton pair production in the photodisintegration of the deuteron process. The complete seven-fold differential cross section is calculated via the Bethe-Heitler mechanism with final state interactions taken into account. The…
The fundamental description of both structural properties and reactions of light nuclei in terms of constituent protons and neutrons interacting through nucleon-nucleon and three-nucleon forces is a long-sought goal of nuclear theory. I…
The Bethe-Salpeter equation for three bosons with zero-range interaction is solved for the first time. For comparison the light-front equation is also solved. The input is the two-body scattering length and the outputs are the three-body…
A three-dimensional approach based on momentum vectors as variables for solving the three nucleon Faddeev equation in first order is presented. The nucleon-deuteron break-up amplitude is evaluated in leading order in the NN T-matrix, which…
The nucleon-nucleon interaction is constructed by means of the $J$-matrix version of inverse scattering theory. Ambiguities of the interaction are eliminated by postulating tridiagonal and quasi-tridiagonal forms of the potential matrix in…
The low-energy $\Xi$-deuteron scattering is investigated through the solution of Faddeev equations, employing three sets of the currently available parametrization of the $\Xi$-nucleon interactions. One of these is the chiral NLO…
The reaction $\gamma + p\to \eta^\prime + p$ is investigated in the quark model approach. The quark model predicts that the off-shell contributions from the resonance $S_{11}(1535)$ dominate the $\etap$ production in the threshold region.…