J. Bruinsma

Potential Effects in Nucleon-Deuteron Scattering

Abstract Nucleon-deuteron elastic scattering and break-up cross sections have been calculated using many different S-wave rank one separable potentials. A correlation between the different results and the intrinsic strength of the interaction has been found. A proper treatment of the high energy repulsion improves agreement with experiments. The Coulomb interaction has been included in an approximate way.

Neutron-neutron effective range parameters from kinematically complete experiments on the reaction 2H(n, 2n)1H

Abstract In simultaneous complete experiments on the reaction 2 H(n, 2n) 1 H neutron-neutron and neutron-proton final-state interactions were observed. The experiments were analysed with three-body calculations using different form factors for the nucleon-nucleon interactions. The analysis with a complete charge dependent calculation using exponential form factors gave a nn = −16.3 ± 1.0 fm for the 1 S 0 neutron-neutron scattering length and r nn = 2.13 ± 0.4 fm for the effective range.

Calculations of the triton binding energy for Reid's soft-core nucleon-nucleon interaction☆

Abstract The triton energy ET has been calculated variationally for Reids soft-core potential. The L · S - term and the 1D2, 3D2 states contribute - 2 MeV and +0.2 MeV resp. The odd-state contribution is negligibly small. Our results are compared with those of other authors.

Nucleon-deuteron breakup quantities calculated with separable interactions including tensor forces and P-wave interactions

Abstract Nucleon-deuteron breakup calculations at a nucleon bombarding energy of 22.7 MeV have been performed with separable interactions including a tensor force and P-wave interactions. Differential cross sections and a selection of polarization quantities have been computed for special regions of the phase space. The influence of a tensor force and P-wave interactions on the differential cross section is of the order of 20 %. Large discrepancies between theory and experiment occur for the vector analyzing powers, both for the kinematically complete and for the incomplete situation. The calculations show that there are kinematical situations in which the differential cross sections and the tensor analyzing powers are sufficiently large to make measurements feasible.

Determination of the n-n scattering length from the2H(n, np)n reaction at bombarding energies between 17 MeV and 27 MeV

Abstract The n-n final-state interaction has been investigated in a kinematically complete experiment with high statistical accuracy via the 2 H(n, np)n reaction. An intense neutron beam with a continuous energy spectrum up to 27 MeV was used and protons and neutrons were detected in coincidence, probing a region of phase space not investigated before at these energies. The Monte Carlo analysis with exact, charge dependent three-body calculations with S-wave rank-one separable potentials and exponential form factors yields a nn = −16.9 ± 0.6fm for the n-n scattering length. A comparison with calculations by P. Doleschall including P- and D-waves as well as a tensor force suggests that the theoretical error is much smaller than the experimental uncertainty.

Neutron-neutron scattering length from the 2H(n, np)n reaction at bombarding energies up to 27 MeV

Abstract The n-n interaction has been investigated in a kinematically complete experiment with high statistical accuracy via the 2H(n, np)n reaction at bombarding energies up to 27 MeV, extending previous measurements to higher energies and to a different geometry. The analysis with exact three-body calculations yields ann = −16.9 ± 0.6 fm.

Nucleon-deuteron breakup quantities calculated with separable interactions including tensor forces and p-wave interactions

Abstract Nucleon-deuteron breakup calculations at 22.7 MeV with separable interactions including tensor forces and P-wave interactions have been performed. Quantitative results of final state interaction peak cross sections and a number of polarization quantities are given.

Potential effects in nucleon--deuteron scattering

Nucleon-deuteron breakup cross sections have been calculated using different S-wave rank one separable potentials. A proper treatment of the high energy repulsion improves the agreement with experiments. For accurate comparisons the inclusion of exact charge dependence in the calculations is important. A strong correlation between the three body-results and the intrinsic strength of the interaction has been found.

SENSITIVITY OF 3H AND 3He PROPERTIES ON LOW-ENERGY NUCLEON-NUCLEON SCATTERING PARAMETERS, USING A DELTA-SHELL NUCLEON-NUCLEON POTENTIAL

Publisher Summary This chapter reviews three-nucleon bound-state properties using delta-shell nucleon–nucleon interactions. Two reasons for the use of delta-shell potential are (1) with an appropriate choice of the potential parameters, an amazingly good fit to the 1S0 and 3S1 phase shifts is obtained and (2) as the potential is local, several three-nucleon properties can be calculated easily using the hyperspherical harmonics formalism. The bound-state properties are much more sensitive with respect to variations in the effective ranges than to variations in the scattering lengths. There is almost no dependency on the singlet scattering length. The large sensitivity for the singlet effective range is interesting as its experimental error is considerable and a change of the parameter within its error could give a variation in binding energy of about 500keV. Until the value of that parameter is better known, not much can be done with the dependency on the other parameters.

NUCLEON-DEUTERON BREAKUP QUANTITIES CALCULATED WITH SEPARABLE INTERACTIONS INCLUDING TENSOR FORCES AND HIGHER PARTIAL WAVES

Publisher Summary This chapter describes nucleon–deuteron breakup quantities calculated with separable interactions including tensor forces and higher partial waves. It presents nucleon–deuteron breakup calculations at 22.7 MeV nucleon bombarding energy with separable interactions including tensor forces. The Faddeev equations are solved with the Fuda–Tuivenberg method. The angular momentum analysis is done the same way as Doleschall. The calculations are performed with charge-independent interactions: Y–Y7, Y–Y0, E–E0, and Y–E0 (the first letter indicates the singlet form factor, the second the triplet one and the number gives the percentage D-state). The chapter presents a comparison of the n–d breakup cross sections for the Y–Y7 and Y–Y0 potential. Comparison made at all angle combinations from Petersen shows that the quasi free scattering peaks are little influenced by the tensor force. The final state peak is more sensitive. The chapter presents a comparison of the FSI peaks for the chosen interactions. The differences between the tensor potential and Y–Y0 behave qualitatively in the same way as the differences between other S-wave potentials.