Proton Total Reaction Cross Sections Research Articles

Comparison of validation methods of simulations for final state interactions in hadron production experiments

Neutrino cross section and oscillation measurements depend critically on modeling of hadronic final state interactions (FSI). Often, this is one of the largest components of uncertainty in a measurement. This is because of the difficulty in modeling strong interactions in nuclei in a consistent quantum-mechanical framework. FSI models are most often validated using hadron-nucleus data which introduces further uncertainties. The alternative is to use transparency data where the hadron starts propagating from inside the nucleus and the probability of interaction is measured as a function of hadron energy. This work examines the relationship between the $\pi^+$ and proton total reaction cross section and transparency from a simulation viewpoint.

Modelled Excitation Functions of 112,114,116,118,120,122,124Sn Isotopes for an Incident Energy Range of 10-80 MeV

The data of the cross–section is required for understanding nuclear reaction mechanism, developing and testing validity of available nuclear reaction models as much as it has been used in the applied fields of nuclear physics. Reliable experimental data is importance of comparison with theoretical nuclear model calculations for testing predictive ability. In the event that experimental data failure appearance, theoretical models are filling this gab for supplying with calculated data. Because of these reasons, both of experimental and theoretical studies need of each other. For a long time, theoretically studies have been carried out for proton total reaction cross section calculation. At the end of these studies, several analytical equations have been proposed by their authors. Comparison of the suggested equations and rearrangement for different value of parameters are enormously important for reaching successfully results. In this study, proton total reaction cross sections have been calculated for 112,114,116,118,120,122,124Sn isotopes using proton-nucleus interaction analytic equation that was proposed by M.A. Alvi. Also, optical model calculations carried out for same reactions by TALYS code. Excitation functions have been plotted with collected experimental data up to 80 MeV proton incident energy. Coefficient comparisons have been made via determined excitation function curves. The obtained results have been discussed by way of the excitation function graphics and compared with the available experimental data. Satisfactory agreements have been seen between calculated data and its measured equivalents. A validation of used theoretical model has been confirmed and tested via obtained results for these Sn isotopes and these energy ranges.

Dispersive optical-model potential for protons in 100 ⩽ A ⩽ 132 even–even tin isotopes

Data on single-particle energies, differential elastic-scattering cross sections, and total cross sections for proton-induced reactions on stable tin isotopes were analyzed on the basis of the dispersive optical model. Good agreement with experimental data was obtained by setting the parameters of the dispersive optical potential to values averaged over the tin isotopic chain and by assuming that the dependence of surface absorption on the neutron–proton asymmetry is close to a traditional dependence. Predictive calculations for single-particle proton spectra and total reaction cross sections were performed for the doubly magic isotopes 100,132Sn. The calculated values of the energy gap between the 1h11/2–1g7/2 and 1g7/2–2d5/2 states were found to be in good agreement with the results of calculations performed with allowance for the tensor component of the effective nucleon–nucleon interaction.

Study of Different Forms of Density Distributions in Proton–Nucleus Total Reaction Cross Section and the Effect of Phase in NN Amplitude

Proton total-reaction cross-section (σR), measurements for about five nuclei in the range 12C to 208Pb at beam energies spanning 40–800 MeV have been analyzed in a systematic way by using the optical limit approximation of the Coulomb-modified Glauber multiple scattering theory. Two different phenomenological nuclear density distributions of the target nucleus in addition to the realistic one have been used in the present analysis. By applying the energy dependence in the slope parameter of nucleon–nucleon (NN) scattering amplitude, it is found that in general, the predictions of σ R with the phenomenological Gambhir and Patil density distribution agree fairly well with the experimental data. The inclusion of phase in the NN amplitude improves the theoretical results. Our analysis shows that the calculated total reaction cross sections closely reproduce the measured data over the whole range of energy considered in this work. To validate our analyses, we have also obtained a fairly good representation of elastic p-nucleus differential scattering cross section data. The effect of a Coulomb energy shift in the proton beam has also been studied.

30–300 MeV proton-nucleus total reaction cross sections

A functional form has been used to analyze proton total reaction cross sections on stable and unstable target nuclei. For proton or incident nuclei energy per nucleon in the range between 30 and 300 MeV, the parameter values in this functional are interpreted in terms of the nuclear-matter distribution by using reliable total reaction cross-sectional data.

Microscopic study of total reaction cross-sections for proton on deuteron, 3 He and 4 He at energy range 20 to 50 MeV

Working within the framework of Coulomb modified Galuber model and using harmonic oscillator shell model target density, the proton total reaction cross-sections on the deuteron, 3 He and 4 He have been analyzed in the beam energy range 20 to 50 MeV. A very satisfactory agreement with experimental data for p-deuteron and to some extent for p3 He have also been achieved. For p4 He, the calculated reaction cross-section becomes negative at lower energies which is absolutely unphysical. Keywords: Coulomb modified Glauber model; Microscopic analysis; Harmonic oscillator shell model density PACS: 25.40.Cm; 25.40.Dn; 24.10.Ht; 25.70Bc

Microscopic Study of Total Reaction Cross-sections for Proton on Deuteron, 3 He and 4 He at Energy Range 20 to 50 Mev

Working within the framework of Coulomb modified Galuber model and using harmonic oscillator shell model target density, the proton total reaction cross-sections on the deuteron, 3 He and 4 He have been analyzed in the beam energy range 20 to 50 MeV. A very satisfactory agreement with experimental data for p-deuteron and to some extent for p- 3 He have also been achieved. For p- 4 He, the calculated reaction cross-section becomes negative at lower energies which is absolutely unphysical.

Calculation of proton total reaction cross sections for some target nuclei in incident energy range of 10–600 MeV

In this study, proton total reaction cross sections have been investigated for some isotopes such as 12C, 27Al, 9Be, 16O, 181Ta, 197Au, 6Li, and 14N by a proton beam up to 600 MeV. Calculation of the proton total cross sections has been carried out by the analytic expression formulated by M.A. Alvi by using Coulomb-modified Glauber theory with the Helm model nuclear form factor. The obtained results have been discussed and compared with the available experimental data and found to be in agreement with each other.

Study of proton total reaction cross section using a Helm model nuclear form factor

An analytic expression for proton–nucleus total reaction cross section has been developed within the framework of Coulomb modified Glauber multiple scattering theory using an approximate form of the Helm model form factor for the distributions of nucleons within nuclei. Without free parameters, the expression reproduces fairly well the proton total reaction cross section data at energies spanning 20–860 MeV. Excellent fits to the experimental data have been achieved using basically one free parameter, plus one other independent of beam energy.

Proton Reaction Cross Sections as Measures of the Spatial Distibutions of Neutrons in Exotic Nuclei

Proton and neutron densities from Skyrme-Hartree-Fock calculations of a number of nuclei with masses ranging from 28 to 58 have been used to generate optical potentials for proton elastic scattering. Those potentials, generated by folding the structure functions with effective in-medium nucleon-nucleon (NN) interactions, have been used to evaluate proton total reaction cross sections; cross sections that reveal signatures of the structures.

EFFECT OF COULOMB ENERGY SHIFT ON PROTON TOTAL REACTION CROSS-SECTION

In this work we study the effect of the Coulomb energy shift on proton total reaction cross-section (σ R ) at 25, 50, and 100 MeV for several nuclei in the mass region 12≤A≤208. The cross-sections are computed using the Coulomb modified Glauber model in the optical limit approximation, and the semi-phenomenological proton and neutron density distributions. We find that the Coulomb energy shift has a significant effect on the calculated σ R , and that it brings the theory quite close to the experiment.

Measuring system of proton total reaction cross-sections at tandem energy region

Proton total reaction cross-sections of nat Si and nat Al have been measured by using a very simple attenuation technique. Energy range is 14– 17 MeV , which covers the threshold energy of 28 Si (p,n). Features include well-defined beam and very low noise counters, elastic and inelastic scattering corrections. The energy dependence of total reaction cross-sections of nat Si shows a resonance-like behavior just above the 28 Si (p,n) threshold energy.

Toward a global exciton model: the equilibrium component

The shell corrections to the equilibrium state densities in the exciton model code PRECO-E have been revised by adding a correction to the level density parameter and by modifying the energy shift based on the set of single particle states from the pre-equilibrium calculations. The range of mass numbers over which shell structure washes out was increased in both parts of the calculations. Additionally, the proton total reaction cross sections below the Coulomb barrier have been extended to lower energies, and a global function has been applied to reduce their intensity. Finally a method of compensating for the lack of gamma-ray competition with secondary particle evaporation in the calculations has been added.

Measurements of proton total reaction cross sections for 112,114,116,118,120,122,124Sn from 22 to 48 MeV

Using a standard beam attenuation technique, proton total-reaction cross sections (σR) were measured for seven even isotopes of tin (112,114,116,118,120,122,124Sn) from 22 to 48 MeV with a typical accuracy of 2–3%. Two parameterizations of the data are presented, one based on an expression for the nuclear transparency, and the other on a semiempirical relation that has recently been developed.

Measurements of proton total reaction cross sections for 58Ni and 60Ni including nonrelativistic and relativistic data analyses.

Using a standard beam attenuation technique, proton total reaction cross sections (${\mathrm{\ensuremath{\sigma}}}_{\mathit{R}}$) for $^{58}\mathrm{Ni}$ and $^{60}\mathrm{Ni}$ have been measured at seven incident energies from 23 to 48 MeV to an absolute accuracy of 1 to 3%. The results have been compared both with nonrelativistic optical model predictions using global parameters and a relativistic optical model using a standard mixture of potential terms. Nuclear trans- parency calculations have also been made for these nuclei using all published data below 100 MeV.

Proton total reaction cross sections for 42Ca, 44Ca, and 48Ca between 21 and 48 MeV.

Proton total reaction cross sections (${\mathrm{\ensuremath{\sigma}}}_{\mathit{R}}$) have been measured for the nuclei $^{42}\mathrm{Ca}$, $^{44}\mathrm{Ca}$, and $^{48}\mathrm{Ca}$ at seven energies each between 20.8 and 48.0 MeV. The experimental results plus our previously measured ${\mathrm{\ensuremath{\sigma}}}_{\mathit{R}}$ values for $^{40}\mathrm{Ca}$ are compared to the results of optical model analyses, both nonrelativistic and relativistic, of an extensive set of elastic scattering data for the same calcium isotopes in this energy range. The experimental results are also compared to global optical model predictions. In general, the theoretical values are in good agreement with the experimental results, with a slight preference for the relativistic analysis. In addition, our results are used in nuclear transparency calculations, which show that over the range of energies studied, the average nuclear transparency decreases by almost 15%.

A study of proton total reaction cross sections for several medium-mass nuclei between 20 and 48 MeV

Proton total reaction cross sections (σR) have been measured for 51V, 54Fe, 56Fe, 57Fe, and 59Co at seven incident proton energies between 20.8 and 47.8 MeV at the University of Manitoba's Cyclotron Laboratory. Our results are compared with an optical-model analysis using global parameters. In general, the predicted total reaction cross sections agree quite well with the measured values. Nuclear transparency calculations have been made for these nuclei using all existing data between 8 and 100 MeV, and nuclei are found to be most reactive between 10 and 25 MeV, with nuclei becoming increasingly transparent as the incident proton energy increases above about 25 MeV. Using previously measured data from Si to 68Zn, along with the current measurements, we observe that when nuclear size effects are removed, the reaction cross section shows departures from average behavior near shell closings corresponding to N or Z values of 20 and 28.

Measurements of proton total reaction cross sections for 6Li, 7Li, 14N, 20Ne and 40Ar between 23 and 49 MeV

Measurements of proton total reaction cross sections for 6Li, 7Li, 14N, 20Ne and 40Ar have been made in the energy range 23 to 49 MeV, using a variation of a standard attenuation technique. The measured cross sections are compared with optical-model and nuclear-transparency calculations.

Proton loss by nuclear inelastic interactions in germanium

The probability of protons undergoing nuclear inelastic interactions while stopping in germanium has been measured in a direct counting experiment using protons with energies between 25 and 49 MeV incident on a germanium detector. These values have been determined to an accuracy of approximately ±2%. Calculations of the proton reaction probability over the incident energy range 20–150 MeV have also been made, using previously reported proton total reaction cross sections. The experimental and calculated results agree to within ±1.8%.

Measurement of the proton total reaction cross section for 159Tb, 181Ta and 197Au between 20 and 48 MeV

Proton total reaction cross sections have been measured for the nuclei 159Tb, 181Ta and 197Au at seven proton energies between 20 and 48 MeV using an attenuation technique. The experimentally determined energy dependence of the total reaction cross sections is compared with results obtained for black nucleus and optical model calculations.