Modern Chiral Forces Applied to the Neutron-Deuteron Breakup Reaction

We report on applications of the recent chiral potentials from the Bochum-Bonn group to the description of the neutron induced deuteron breakup observables. Specifically, we discuss the convergence of predictions with respect to the chiral order and the dependence of our results on the value of the regularization parameter. To that end we use the chiral forces with semi-local coordinate or momentum space regularization up to the N$$^4$$ 4 LO$$^+$$ + order of chiral expansion. We find a satisfactory picture revealing high quality of the chiral forces used.

Perturbative Treatment of Three-Nucleon Force Contact Terms in Three-Nucleon Faddeev Equations

We present a perturbative approach to solving the three-nucleon continuum Faddeev equation. This approach is particularly well suited to dealing with variable strengths of contact terms in a chiral three-nucleon force. We use examples of observables in the elastic nucleon-deuteron scattering as well as in the deuteron breakup reaction to demonstrate high precision of the proposed procedure and its capability to reproduce exact results. A significant reduction of computer time achieved by the perturbative approach in comparison to exact treatment makes this approach valuable for fine-tuning of the three-nucleon Hamiltonian parameters.

Application of the JISP16 potential to the nucleon induced deuteron breakup process at E=13 MeV and E=65 MeV

The JISP16 nucleon-nucleon potential has been applied to investigations of the nucleon induced deuteron breakup reaction at the incoming nucleon laboratory energies E = 13 MeV and E = 65 MeV. We have found that for the studied process the JISP16 force gives a description of the exclusive cross section, which is generally similar to the ones obtained with the standard realistic nucleon-nucleon AV18 interaction. However, there are some regions of the phase space where the differential cross sections predicted by the JISP16 and AV18 models, differ by more than 100 %. These special kinematical configurations may possibly be useful to refit the JISP16 force parameters.

Determination of phase space region for cross-check validation of the neutron detection in the BINA experiments

Deuteron breakup reactions are basic laboratories for testing nuclear force models. Recent improvements in the data analysis allow for direct identification of neutrons in the BINA detection setup. This opens up the opportunity to study new aspects of few-nucleon system dynamics like charge dependence of nuclear force or Coulomb interaction. In this paper we determine regions along the kinematical curves where differential cross section of deuteron-proton breakup reactions can be measured by the proton-neutron and proton-proton coincidences simultaneously. %In this paper we determine regions along the kinematical curves where differential cross section of $^1$H$(d,pp)n$ and $^1$H$(d,pn)p$ breakup reactions overlap. This is particularly useful for validation of the neutron detection technique.

Current stage of studies of the star configurations at intermediate energies with the use of the BINA detector

The~Space Star Anomaly in proton-deuteron breakup cross-section occurs at energies of about 10~MeV. Data for higher energies are sparse. Therefore, a~systematic scan over star configurations in the~range of intermediate energies between 50 and 100 MeV/nucleon is carried out on the~basis of data collected with the~large acceptance BINA detector. The~preliminary cross section results for forward star configurations at 80 MeV/nucleon slightly surpass the~theoretical calculations, but the~systematic uncertainties are still under study. Also, a~new variable describing rotation of star configurations is proposed.