Differential cross sections for np and nd elastic scattering near 130 MeV

We have measured the np (nd) elastic scattering cross sections at 25(17) angles in the interval 30°–168° (c.m.), using a neutron beam with a broad spectrum peaked near 130 MeV. At backward angles the outgoing charged particles from a liquid hydrogen (deuterium) target were detected; at forward angles we detected neutrons scattered from a hydrogenated (deuterated) scintillating target. Cross sections have been normalized to the energy dependent solution of the Livermore nucleon-nucleon partial wave analysis, evaluated at 130 MeV. The np measurements represent a marginal improvement on previous work; the nd cross sections show some differences from pd measurements, in agreement with earlier indications at an energy of 152 MeV.     

Spin observables in small-angle elastic → d scattering with an L-type deuteron target at 800 MeV

We have measured spin correlation parameters that describe the elastic scattering of 800 MeV polarized protons from an L-type polarized deuteron target at laboratory angles below 20°. The measured parameters include the correlated analyzing powers A_SL, A_LL and A_NLL and the proton spin-transfer coefficients C_0L,S, C_0L,L, C_SL,N, C_NL,S, C_NL,L and C_LL,N. The results are compared with single-scattering predictions based on different phase-shift solutions for the nucleon-nucleon scattering matrix.     

Proton-nucleus elastic scattering at 156 MeV

Cross sections for the elastic scattering of 156 MeV protons on eleven targets ranging from ¹²C to ²⁰⁹Bi were measured and an optical model analysis has been performed. The effect of different optical potentials in DWIA inelastic scattering calculations is shown by some examples.     

Neutron-proton elastic scattering at 325 MeV

Accurate measurements of the P and D_T parameters in np elastic scattering at 325 MeV resolve a major ambiguity in the phase shift analysis. The mixing parameters $\text{ε}{}_1\text{= 8.4 ± 0.6°}$ and $\text{ε}{}_3\text{= 7.2 ± 0.4°}$ are particularly well determined, and in good agreement with theoretical expectations.     

Small-angle elastic scattering of 2.5 MeV neutrons

Differential cross sections and asymmetries of 2.50 MeV polarized neutrons elastically scattered by In, Ho, Hg, Bi and U have been determined for scattering angles from 2.1° to 9.1°. The measurements were carried out by the use of a neutron positional spectrometer. The results, when compared with the predictions of the electromagnetic interaction, indicate some deviation of 〈σ(θ)P(θ)〉 from the expected values. The observed cross sections are systematically greater than those evaluated within the framework of the optical model.     

Diffraction model analysis of pion-12C elastic scattering at 800 MeV/c: Optical potential by inversion

Elastic scattering of 800 MeV/c pions by¹²C has been studied in the diffraction model with a view to determine pion optical potential by the method of inversion. Finding an earlier diffraction model analysis to be deficient in some respects, we propose a Glauber model based parametrization for the elasticS-matrix and show that it provides an exceedingly good fit to the pion-carbon data. The proposed elasticS-matrix gives a closed expression for the pion-¹²C optical potential by the method of inversion in the high energy approximation.     

Measurement of np elastic scattering at high energies and very small momentum transfers

The np elastic differential cross section has been measured for incident neutron momenta 100–400 GeV/c in the |t| range 6 · 10^?6 ? 5 · 10^?1 (GeV/c)². The np data of this experiment provide a first direct measurement of the hadronic amplitude for |t| < 10^?2 (GeV/c)², which is consistent with the extrapolations from higher |t| values. Our data for |t| < 10^?4 (GeV/c)² are consistent with a rise which can be attributed to Schwinger scattering, caused by the interaction of the neutron magnetic moment with the proton.     

Effects of nuclear spin on the elastic scattering of 5 MeV neutrons

Angular distributions have been measured for 5 MeV neutrons elastically scattered from Zr, Nb, Ag, Sb, Ce, Pr, Ta, Au, Tl, RadioPb, Th, and U. Corrections for multiple scattering and finite geometry were calculated using a Monte-Carlo program. The data have been fitted with a local potential optical model and compared with the predictions of a non-local potential model. There is evidence of distortions of the angular distributions attributable to nuclear deformations but there are no observable effects from interactions involving nuclear spins. The cross section for compound-elastic scattering appears to be negligibly small except for Tl and RadioPb.     

Measurement of neutron elastic scattering cross sections for carbon at 134 MeV

Angular differential neutron elastic scattering cross sections have been measured by using a ⁷Li(p,n) quasi-monoenergetic neutron beam. The neutron beam whose peak energy is 134 MeV was incident upon a natural carbon sample, and the scattering neutrons were measured by liquid organic scintillators with the time-of-flight (TOF) technique. The results were compared with the existing experimental data measured by a recoil-proton telescope, and the evaluated nuclear data of JENDL/HE-2007 and ENDF/B-VII.0.     

The neutron-proton scattering length in the reaction9Be(p,np)8Be at 7.5 MeV

The relative differential cross section of the⁹Be(p, np)⁸Be _gs reaction at 7.5 MeV has been measured in an FSI geometry. A strongn-p FSI peak was observed with virtually no sequential decay modes interfering. The Watson-Migdal analysis of this peak yields the scattering lengtha _np =–23.8_–1.2 ^–1.1 fm with the effective ranger _np =2.76 fm.     

Elastic scattering based on energy-dependent relativistic Love-Franey model at energies between 20 and 800 MeV

In order to investigate the elastic scattering,we fit scattering observables of the weighted fits (WF16)with the relativistic Love-Franey (RLF) model.The masses,cutoff parameters,and initial coupling strengths of RLF are assumed to be independent of energy.Because the energy boundary between low energy and high energy is around 200 Me V,the masses,cutoff parameters,and initial coupling strengths of RLF are obtained by fitting scattering observables of WF16 at an incident energy of 200 MeV.With t...     

The elastic scattering of 33 MeV He particles from Ni,Cu and Zn

Differential cross sections have been measured for the elastic scattering of 33 MeV ³He particles from targets of ^58,60,62,64Ni,^63,65Cu and ^64,66,68Zn over the angular range 5° to 175°. The data have been analysed with the optical model, with particular emphasis on the investigation of the ambiguities in the real potential, the form of the imaginary potential and the use of a spin-orbit term.