Related papers: Three Body Force in Peripheral $N\alpha$ Scatterin…
We study elastic N$\alpha $ scattering and produce a quantitative correlation between the range of the effective potential and the energy of the system. This allows the identification of the waves and energies for which the scattering may…
We propose and demonstrate that peripheral neutron-$\alpha$ scattering at low energies can serve as a sensitive and clean probe of the long-range three-nucleon forces. To this aim, we perform {\it ab initio} quantum Monte Carlo calculations…
We consider the relationship between P-wave pi-N scattering and the strength of the P-wave two-pion-exchange three-nucleon interaction (TPE3NI). We explain why effective theories that do not contain the delta resonance as an explicit degree…
Three-nucleon forces have been considered to be one possibility to resolve the well known discrepancy between experimental values and theoretical calculations of the nucleon analyzing power in low energy nucleon-deuteron scattering. In this…
Effects of three-nucleon forces arising from the exchange of a pion and a scalar-isoscalar object among three nucleons on nucleon-deuteron scattering observables are studied.
The leading contribution to the three-pion exchange nucleon-nucleon potential is calculated in the framework of chiral symmetry. It has pseudoscalar and axial components and is dominated by the former, which has a range of about 1.5 fm and…
We present the two- and three-pion exchange contributions to the nucleon-nucleon interaction which occur at next-to-next-to-next-to-next-to-leading order (N4LO, fifth order) of chiral effective field theory, and calculate nucleon-nucleon…
The contribution of a $\pi \pi$-exchange three-body force to the three-nucleon binding energy is calculated in terms of a $\pi N$ amplitude. The latter is based on a meson-theoretical model of $\pi N$ interaction developed by the J\"ulich…
Available data on large-angle nucleon-deuteron elastic scattering $Nd\to dN$ below the pion threshold give a signal for three-body forces. There is a problem of separation of possible subtle aspects of these forces from off-shell effects in…
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…
Parity nonconserving two-pion exchange in elastic pp scattering is investigated in the presence of phenomenological strong distortions in various models. Parity violation is included in the nucleon-pion vertex considering NN and N…
The nucleon-nucleon interaction arising from the exchange of three pions and the excitation of $\Delta(1232)$-isobars in intermediate states is studied. Approximating the $\Delta$-propagator by the inverse $\Delta$N mass-splitting,…
We evaluate, within one-loop chiral perturbation theory, the two-pion exchange diagrams with single and double delta-isobar excitation contributing to elastic NN-scattering. We find that virtual $\Delta$-excitation processes (in the static…
We report on recent results obtained by the above collaboration on the collision processes involving three nucleons, where we pay particular attention on the dynamical role of the pion. After discussing the case at intermediate energies,…
We construct a phenomenological three-nucleon force (3NF) model that gives a good description of polarization observables in elastic nucleon-deuteron (N-$d$) scattering at a low energy together with a realistic nucleon-nucleon force and a…
The elastic backward proton-deuteron scattering is analyzed within a covariant approach based on the Bethe-Salpeter equation with realistic meson-exchange interaction. Contributions of the one-nucleon and one-pion exchange mechanisms to the…
A meson exchange model of the $\pi\pi$ interaction which fits free $\pi\pi$ scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions…
Contributions of three-nucleon forces (3NF) to proton-deuteron scattering observables at energies below the deuteron breakup threshold are studied by solving the Faddeev equation that includes the Coulomb interaction. At E_p=3.0 MeV, we…
We show that the tail of the chiral two-pion exchange nucleon-nucleon potential is proportional to the $\pi N$ scalar form factor and discuss how it can be translated into effective scalar meson interactions. We then construct a kernel for…
Peripheral nucleon-nucleon scattering is analysed in the framework of an effective field theory. Distorted-wave methods are used to remove the effects of one-pion exchange. Two-pion exchange and recoil corrections to one-pion exchange are…