Elastische und unelastische Streuung von Deuteronen an C,Mg, Ti,Fe, Ni,Cu und Zn bei 11,8 MeV

The spectra of deuterons scattered from C, Mg, Ti, Fe, Ni, Cu and Zn have been measured in steps of 5° betweenΘ _lab=20° and 165°. The excitation of the lowest levels is in most nuclei strongly preferred and only very few low energy deuterons were observed. The angular distributions of the elastic and inelastic scattering of deuterons show pronounced diffraction maxima which are partly correlated. The correlation is compared with the Blair-model.     

Proton reactions with 17O: (I). Elastic and inelastic scattering reactions

Differential cross sections for the elastic and inelastic scattering of protons by ¹⁷O have been measured at 8.62, 9.45 and 10.5 MeV. Excitation functions at 110° and 140° were measured from 8.5 to 10.5 MeV. The elastic scattering angular distributions were used to find optical model parameters for the scattering. The angular distributions of inelastically scattered protons were analysed using the effective interaction method of Satchler, and also with the microscopic theory of Geramb and Amos.     

Optical model and coupled-channel analysis of 60–90 mev deuteron scattering from24Mg and89Y

Angular distributions of deuterons scattered from²⁴Mg and⁸⁹Y in the angular range 12 °→100 ° have been measured atE _d=60, 77 and 90 MeV. With some exceptions the elastic and inelastic data were found to be described consistently by the optical model approach and by coupled-channel analysis, respectively. Collective model features of²⁴Mg are derived from the inelastic scattering results.     

Investigation of fast neutron interaction with235U

The angular distribution of neutrons emitted by elastic, inelastic and fission processes on²³⁵U were measured at the incident neutron energies of 1.5, 1.9, 2.3, 4.0, 4.5, 5.0 and 5.5 MeV using nanosecond time-of-flight technique. The differential elastic scattering cross sections and their angular distributions at all the seven energies are presented. The total elastic scattering cross sections, angle and energy integrated cross sections for the inelastically scattered neutrons in energy bands of 200 keV, fission cross sections and the angular distributions of fission neutrons were extracted at 1.5, 1.9 and 2.3 MeV incident neutron energies. The energy distributions of the prompt fission neutrons and of the inelastically scattered neutrons are given at the incoming neutron energies of 1.5, 1.9 and 2.3 MeV; and the average fission neutron energies and the inelastic neutron evaporation temperatures were also evaluated at these energies.     

Elastic and inelastic scattering of 15 MeV polarized deuterons from isotopes of Ca,Cu, Sr,Zr, and Mo

The elastic and inelastic scattering of 15 MeV polarized deuterons from ⁴⁸Ca, ⁶³Cu, ⁸⁸Sr, ⁹⁰Zr, ⁹²Zr, and ⁹²Mo has been investigated. Angular distributions of the cross section and vector analyzing power iT₁₁ have been measured for all these nuclei; the tensor analyzing powers T₂₀ and T₂₂ have been studied for ⁹²Zr. Cross sections and vector analyzing powers are generally well explained by the optical model for elastic scattering and by the DWBA with a macroscopic form factor for the inelastic scattering; this is consistent with previous work. Distributions for ⁴⁸Ca, however, are poorly fitted. Anomalous behavior of the N = 50 nuclei found in the inelastic scattering of polarized protons is not present for deuterons. Tensor analyzing powers are not well explained by standard procedures: use of approximate folding model optical parameters did not improve the fits. The distribution of iT₁₁ for the $\text{1}\text{2}$^? state in ⁶³Cu is significantly different from the distributions for the $\text{5}\text{2}$^? and $\text{7}\text{2}$^? states.     

Nuclear and Coulomb deformation parameters of 142Nd

Nuclear and Coulomb deformation parameters have been deduced from DWBA analyses of angular distributions of 67.5 MeV ¹³C ions inelastically scattered from ¹⁴²Nd. Optical model parameters from fits of measured elastic scattering data were used with previously measured B(EL) values to determine initial deformation parameters. Comparison With the experimental data indicates that DWBA calculations can be used to understand the inelastic scattering from the nearly spherical nucleus ¹⁴²Nd.     

Eine Gegenfeldanordnung zur Messung von Energie- und Winkelverteilungen gestreuter Elektronen

In a previous paper direct electron-intensity measurements in Debye-Scherrer diagrams of aluminium have been described. A retarding field apparatus was used for investigations into the influence of crystal size and electron energy (15 to 50 keV) on the elastic diffraction intensities. The validity range of the kinematical theory could be determined. By means of a retarding field the inelastically scattered electrons were separated from the elastically scattered electrons (energy loss below 2 eV). In this paper the retarding field apparatus by which scattering intensities can be measured with good accuracy (≈ 2%) is described in detail. It is compared with other arrangements for the measurements of angular and energy distributions of scattered electrons.     

Anomaly in α-scattering from 6Li between 35 and 45 MeV

The elastic scattering of α-particles on ⁶Li nuclei has been measured from 20° to 170° (c.m.) and the inelastic scattering to the first excited state of ⁶Li has been measured for forward and backward angles. The elastic scattering angular distributions are calculated (i) in terms of pure potential scattering, (ii) in terms of potential scattering with an l-cut-off on the imaginary part of the potential and (iii) in terms of the coherent addition of the potential scattering amplitude and of the exchange amplitude. The third method gives the best fit to the data. The inelastic angular distributions are compatible with the macroscopic calculations, except in the very backward region where exchange phenomena are also shown to dominate.     

Weak localization of inelastically reflected electrons under auger emission conditions

A new type of weak localization of electrons emerging during electron emission is considered. It is manifested in singularities of the angular spectra of particles reflected inelastically from a solid and causing Auger ionization of the atoms. The orientational dependences in this case appear as a result of interference of two types of processes. In one case, an electron from the primary beam penetrates the solid, undergoes inelastic scattering, ionizes an atom, and is then scattered elastically through a large angle, after which it leaves the solid. In the other case, elastic scattering of an electron precedes its inelastic scattering due to the Auger ionization of an atom. The azimuthal angular dependences of currents created by inelastically reflected electrons contain information on new processes of weak localization of particles.     

Study of nuclear-coulomb interference effects in inelastic deuteron scattering on 238U

The angular distributions of elastically and inelastically scattered deuterons from ²³⁸U at E = 17 MeV are compared to coupled-channel calculations. The cross sections at small scattering angles are strongly influenced by nuclear-Coulomb interference effects and allow a simultaneous extraction of nuclear (optical potential) and charge quadrupole deformation parameters. Two different deformed Coulomb potentials and the parameters of the optical model are discussed.     

The scattering of fast neutrons from W184

Neutrons with energies of 0.3 to 1.5 MeV are scattered from W¹⁸⁴. Pulsed-beam fast time-of-flight techniques including a magnetic bunching system are utilized to resolve the elastically scattered neutrons from those inelastically scattered. The differential elastic cross section is measured at 50 keV intervals with an ≈20 keV incident neutron energy spread. The differential cross sections for inelastic scattering resulting in the excitation of residual nuclear levels at 111±5, 365±10, 690±40, 900±25, 1000±30, and 1120±30 keV are determined. In all instances the inelastically scattered neutrons are emitted, within experimental error, isotropically. The experimental results are compared with those obtained in previous work and with the predictions of theory.     

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.     

Wirkungsquerschnitt und Winkelverteilung der elastischen und unelastischen Elektronenstreuung in Aluminiumschichten

Absolute intensity measurements of the electrons scattered by a polycrystalline Aluminium foil were carried out in the energy range between 25 and 50 keV. The electrons scattered elastically were separated from those scattered inelastically by means of a retarding field. The intensities of the electrons having passed the foil unscattered and of those which were scattered elastically into the Debye-Scherrerrings and into the continuous background can be interpreted by the assumption of reasonable thicknesses of the crystalline Aluminium and the amorphous Aluminium-Oxide. These values agree approximately with the thickness measured by light absorption. Additionally the probability of the inelastic scattering process can be deduced from these measurements. Investigations of the angular distribution were carried out in order to study the influence of the inelastic scattering on the shape of the primary beam, the rings and the continuous background. The results are discussed in detail. Some results are given in particular, concerning the increase of the half width of the rings due to inelastic scattering processes.     

Wirkungsquerschnitte für elastische und unelastische Elektronenstreuung an amorphen Kohlenstoff- und Germaniumschichten

Absolute intensities of electrons scattered by amorphous carbon and germanium foils were measured for various energies (20–60 keV) and foil thicknesses (200–800 Å). Electrons scattered elastically were separated from those scattered inelastically by means of a retarding field. Thus total cross sectionsσ _e for elastic scattering andσ _u for inelastic scattering were obtained. Agreement of observed and theoretical values is satisfactory, especially regarding the dependence on electron energy.     

Elastic scattering of 13.6 MeV deuterons by light nuclei

Measurements were made of the differential cross section or elastic scattering of 13.6 MeV deuterons by 19 nuclei, from beryllium to iron, and of the cross sections for inelastic scattering corresponding to the excitation of the lower excited levels of beryllium, carbon, titanium-46, and titanium-48. Several features found in the angular distributions are attributed to the interference of Coulomb and nuclear scattering. All the angular distributions are analyzed on the basis of the optical model; a quite good agreement is found between theory and experiment. A calculation is carried out for scattering by titanium-48 by the method of complex angular momenta. This model satisfactorily describes inelastic scattering of deuterons.Translated from Izvestiya VUZ. Fizika, No. 8, pp. 105–113, August, 1970.The authors thank the staff at the cyclotron of the Scientific-Research Institute of Nuclear Physics, Electronics, and Automation, Tomsk Polytechnical Instutute, for the reliable operation of the accelerator; and L. S. Sokolov and K. O. Terenetskii for assistance in the calculations.     

Winkelverteilung von elastisch und mit 6,7 eV-Energieverlust an freien Hg-Atomen gestreuten Elektronen

The angular dependence of electrons scattered elastically and inelastically at free mercury atoms have been measured for electron energies between 20 and 300 eV (angular range from 20 to 155°).     

Study of the fission decay of the isoscalar monopole resonance via the 238U(α, α′) reaction at 0°

The fission decay of ²³⁸U has been investigated using inelastic scattering of 120 MeV ga-particles to excite the ²³⁸U nucleus. Angular correlations of the fission fragments have been measured for excitation energies between 5.7 and 15.7 MeV in coincidence with inelastically scattered α-particles between 0 and 3°. The difference in yield for fission in coincidence with inelastically scattered α-particles between 0–1.35° and 1.35–3° was used to deduce the fission decay of the giant monopole resonance. It was found that in the fission decay channel (22 ± 5)% of the E0 EWSR strength is located between 8 and 15 MeV excitation energy. The distribution of the deduced monopole strength is in agreement with recent theoretical calculations predicting splitting of the giant monopole resonance in deformed nuclei.     

中子与90,91,92,94Zr反应的理论计算和分析

根据中子与天然Zr及其同位素反应的总截面,去弹截面和弹性散射角分布的实验数据,得到一组普适的光学模型势参数;应用得到的光学模型势参数,光学模型,Hauser-Feshbach理论,预平衡反应的激子模型和扭曲波玻恩近似理论,系统计算和分析了中子与^90,91,92,94Zr反应的非弹散射角分布和双微分截面,理论结果与实验很好的一致.     

Elastic and inelastic scattering of 58Ni +90,94Zr

Pure elastic and inelastic scattering cross sections have been measured for the systems ⁵⁸Ni +^90,94Zr at energies near the Coulomb barrier where not only quasi-elastic and fusion but also deep-inelastic process come into play. Coupled channels calculations including both projectile and target inelastic excitations can successfully explain the elastic and inelastic scattering angular distributions with an energy-independent semi-empirical bare potential. The calculation reproduces also the sum of the total quasi-elastic, fusion and deep-inelastic cross sections. Received: 14 September 1998 / Revised version: 21 October 1998     

Elastic and inelastic scattering of 178 MeV protons from 58Ni and 60Ni

The elastic and inelastic scattering of 178 MeV protons from ⁵⁸Ni and ⁶⁰Ni has been studied. Angular distributions were measured for the differential cross sections for elastic scattering as well as inelastic scattering from excited states below about 5 MeV, all with natural parity. For the elastic and for the inelastic scattering from the first excited state (2⁺ in both nuclei, the angular distributions for the polarization were also measured. The measurements extend out to c.m. angles of about 60°, corresponding to a momentum transfer of about 600 MeV/c.The elastic and inelastic scattering data were compared to the results of coupled-channel calculations in the vibrational model using a deformed spin-orbit interaction of the full Thomas form. Good agreement was found in general showing that the main features of the experimental results are well described in this model.