Determination of matter densities of Ca isotopes by 600 MeV and 1 GeV proton elastic scattering

The 600 MeV and 1 GeV data of proton elastic scattering on ^40,42,44,48Ca have been analyzed in the framework of the Glauber model. The matter distributions are extracted from the data in an approximately model-independent form based on a Fourier series expansion. A similar method is used to deduce directly the ⁴⁸Ca⁴⁰Ca neutron density difference.     

Comparisons of vector analyzing-power data and calculations for neutron-deuteron elastic scattering from 10 to 14 MeV

High-accuracy analyzing-powerA _y() data forn-d elastic scattering at 12 MeV have been measured using the polarized-neutron facilities at the Triangle Universities Nuclear Laboratory (TUNL). The present data have been combined with our previousn-d measurements at 10, 12, and 14.1 MeV to form the highest-accuracyA _y() data set forn-d elastic scattering below 20 MeV. These data are compared to recent Faddeev-based neutron-deuteron (n-d) calculations which use the Paris and Bonn equivalent separable potentials PEST and BEST, as well as Doleschall's representation of theP- andD-wave nucleon-nucleon interactions. None of these models adequately describe the data in the angular region around the maximum ofA _y(). Possible reasons for the discrepancies are discussed. The sensitivity of the present Faddeev-based calculations to various angular momentum components of the nucleon-nucleon interaction are examined.     

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.     

Dispersion relations and Glauber model for pion-deuteron scattering

Forward dispersion relations are used to calculate the real part of the elastic amplitude for forward pion-deuteron scattering. The same real part is also calculated from the Galuber multiple scattering model. The results of the two approaches are critically compared in the light of present experiments. A theoretically deduced value for the pion-deuteron scattering length is also given. A theoretical prediction for the pion-deuteron total cross section for energies below 450 MeV is found to agree rather well with experiments.     

Implications of the Glauber model for inelastic hadron-nucleus scattering

The Glauber model for elastic hadron-nucleus scattering is extended to inelastic processes by supplementing it with the Abramovskii, Gribov, Kancheli cutting rules. Inelastic screening due to low mass states is also included. The results can be interpreted in terms of the probabilistic multiple collision model. The mutual relationship of the two approaches is discussed.     

Optical model analysis of proton-carbon elastic scattering in the range 20 to 50 MeV

The differential cross-sections for the elastic scattering of protons from¹²C with incident energies ranging in approximately 2 MeV steps between 20 and 50 MeV, are analyzed using a standard optical model.     

A microscopic optical model analysis of heavy ion elastic scattering data using the realistic NN interaction

The real part of the nucleus-nucleus optical potential has been computed, the direct part by folding in the two density distribution functions with the direct parts of the finite range M3Y and Paris two-body effective interactions and the exchange part by folding in the two density matrices with the exchange parts of the same interactions. The magnitude of the potential as obtained by Satchler and Love at the strong absorption radius is reproduced with a normalisation of 0.92 ± 0.27. The quality of fits does not change appreciably however if the normalisation is changed by 20%.     

Test of the Glauber formula for nucleon-deuteron scattering at intermediate energies

A high-precision test of the Glauber formula for the amplitude of nucleon-deuteron scattering is performed. Nucleon-nucleon amplitudes used in the calculations depend on the spins of interacting particles, phase shifts, and mixing parameters. These amplitudes were derived by using the Njim I, Njim II, Njim 93, and Reid 93 realistic potentials. The differential cross sections for nucleon-deuteron scattering were calculated for the projectile-nucleon energies of 65, 95, 135, 150, 190, and 250 MeV, and the results of these calculations were compared with experimental data.     

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.     

Multiple scattering of heavy ions,Glauber theory,and optical model

An exact multiple-scattering series for the scattering of two heavy ions is derived and compared to the Glauber approximation. An optical model potential operator is indicated which is an accurate approximation to the multiple-scattering formalism.     

Nucleon elastic scattering from 40Ca between 11 and 48 MeV

Differential cross sections for the elastic scattering of neutrons from ⁴⁰Ca have been measured in the 19–26 MeV region. The neutron elastic scattering data, previous neutron measurements and additional proton elastic scattering data are analyzed using three different approaches to the optical model potential: Woods-Saxon parameterization, model independent analysis and microscopic calculations. The difference between the phenomenological neutron and proton real potentials is studied in terms of Coulomb effects, nuclear polarization and charge symmetry breaking in the nuclear mean field.     

Comments on np elastic scattering, 142–800 MeV

Important new data of McNaughton et al. on np Wolfenstein parameters are added to NN phase-shift analysis. At 800 MeV, there is a dramatic improvement and one can see with confidence which way phase shifts are heading from 500 to 800 MeV. Dispersive effects in ³D₁ and ³G₃ herald the onset of I = 0 inelasticity. Phase shifts account naturally for the energy dependence of Δσ_L and Δσ_T for np scattering and do not support the claim of Beddo et al. for an I = 0 dibaryon resonance near 733 MeV.     

Phase-shift analysis of d-α elastic scattering between 3 and 43 MeV

Phase shifts for the d-α elastic scattering have been extracted from differential cross sections and the vector and tensor analyzing powers of ${}^4\text{He(}\text{d}\text{, d)}{}^4$He scattering in the energy range from 3 to 43 MeV. The analysis includes spin-orbit splitting, mixing of states and absorption to reaction channels. A new parametrization of two-channel scattering matrices is given and compared. Excellent fits have been obtained with a new phase-shift code ONEZERO, which is capable of taking into account all degrees of freedom in strong interactions. The Argand-plot method has been used for resonance analysis of the excited ⁶Li system. Five new broad T = 0 resonances above 15 MeV deuteron energy have been found in ⁶Li, corresponding to D₃, F₂, F₃, G₃ and G₄ resonant states. Problems from phase-shift ambiguities are pointed out.     

Optical-model analysis of elastic scattering of 53.4 MeV helions from Fe

Elastic helion scattering from ⁵⁶Fe at 53.4 MeV was measured over the angular range 12° to 150°. Using the regular optical model, real-potential ambiguities, the shape of the imaginary term and the need for a spin-orbit term were explored. Coupled-channels (SCA) calculations based on the ground state and principal 2⁺ and 3⁻ states indicate that such coupling effects are not as dominant as the inclusion of a spin-orbit potential in the regular optical model. Previously reported helion scattering from ⁵⁹Co and ⁶⁰Ni at 50.1 MeV has been included in an average parameter analysis to generalise the improvements in the helion optical-model parameterization in this energy region.