From atoms to nuclei, quarks and bejond...

Latest Results for Few-Body Systems

16 April 2024

• Experiments of Few-Nucleon Scattering to Explore Three-Nucleon Forces

  Abstract

  Few-nucleon scattering offers a good opportunities to study dynamical aspects of three-nucleon forces, that are momentum, spin and isospin dependent. In the paper, the experimental results of deuteron-proton elastic scattering at \(\sim ~\mathrm 100\) MeV/nucleon obtained in the course of the study are presented. The experimental study of few-nucleon scattering has been recently extended to the proton- \(^3 \textrm{He}\) scattering with the aim of approaching the isospin \(T=3/2\) channel in three-nucleon forces. The data are in comparison with the rigorous numerical calculations based on state-of-the-art nuclear potentials with three-nucleon forces.

• Impact of the $$\hbox {N}^4\hbox {LO}$$ Short-Range Three-Nucleon Force Components on the Nucleon-Deuteron Spin Correlation Coefficients

  Abstract

  The spin correlation coefficients in the neutron-deuteron elastic scattering process at incoming neutron laboratory energies \(\hbox {E}=10\) , 135, 190, and 250 MeV are determined by solving the momentum space three-nucleon (3N) Faddeev equations. The chiral two-nucleon (2N) interaction with momentum-space semi-local (SMS) regularization up to the fifth order of chiral expansion ( \(\hbox {N}^4\hbox {LO}\) ), supplemented by the F-waves terms from the sixth order ( \(\hbox {N}^5\hbox {LO}\) ), is used. Additionally, the consistent 3N force (3NF) at the third order of chiral expansion, supplemented by the short-range contributions from \(\hbox {N}^4\hbox {LO}\) is applied. As a results, we give predictions for the complete set of spin correlation coefficients \(C_{\alpha ,\beta }\) . We find that the effect of the investigated three-nucleon \(\hbox {N}^4\hbox {LO}\) components amounts up to several dozen percent, depending on reaction energy, scattering angle and type of spin correlation coefficient itself. Our results can serve as a guide for future measurements of the spin correlation coefficients.

• A New Quantization of Hadron System and Ultra-Low Energy Nuclear Fusion

  Abstract

  A new quantization is proposed for an energy-dependent particle exchange potential. The quantum number corresponds not only to the branch point of the potential cut, but also to the index of a long-range hadron potential. By using the long-range potential, an ultra-low energy nuclear (ULEN) reaction is investigated. It was found that a three-body Cs + H + H plasma in a Pd \(_{12}\) cage could be excited to \(1.36\times 10^{-4}\)  eV  \(\sim 300\)  eV by an electric current where the long-range potential gives one or two order larger reaction probability than the others. A ULEN reaction was compared with the thermo-nuclear fusion by using well-known critical fusion constant defined by \(C_{high/low}\)  = (a duration time)  \(\times \)  (a plasma density)  \(\times \)  (a temperature). We found that \(C_{low}\) is almost the same as \(C_{high}\) or more. We concluded that the ULEN synthesis could occur with a high-pressure hydrogen circumstance and a high-density CsH \(_2\) Pd \(_{12}\) cluster.