N. V. Orlova

αγ angular correlations in the inelastic scattering of α particles on 24Mg at Eα = 30.3 MeV

The results from measuring the angular dependence of differential α-scattering cross sections on 24Mg with final nucleus formation in the ground and three lower excited states are presented, along with the double differential 24Mg(α, αγ)24Mg(2+, 1.369 MeV) reaction cross sections at Eα = 30.3 MeV. The spin-tensor components of the density matrix of the 24Mg nucleus in the 2+(1.369 MeV) state are reconstructed and its orientation characteristics are determined. The experimental results are compared to theoretical results under the assumption of collective excitation and mechanisms for compound nucleus formation.

Investigation of the mechanism of inelastic deuteron scattering on 12C at E d = 15.3 MeV by the method of dγ angular correlations

The results are presented that were obtained by measuring the differential cross sections for the reaction 12C(d,d) 12C occurring at Ed = 15.3 MeV and leading to the production of a 12C nucleus in the ground and the first excited state. The energy dependences of the differential reaction cross sections were measured for three angles of deuteron emission in the range of projectile-deuteron energies Ed between 12 and 15.3 MeV. The double-differential cross sections for the reaction in question were measured for the 2+ state of the 12C nucleus at 4.44 MeV, and the angular dependences of the even spin-tensor components of the density matrix were determined, along with the angular dependences of the populations of magnetic sublevels and the components of the tensors of multipole-moment orientation. These experimental results are compared with their theoretical counterparts obtained under the assumption of various reaction mechanisms, including collective interaction, heavy-particle stripping, a two-step mechanism that takes into account the delay in the interaction, and the mechanism of compound-nucleus formation.

Angular correlations in the inelastic-scattering process 24Mg(d, dγ)24Mg at Ed = 15.3 MeV

The double-differential cross sections for the reaction 24Mg(d, dγ1.369)24Mg at the projectiledeuteron energy of Ed = 15.3 MeV weremeasured for deuteron emission angles in the forward hemisphere. All even spin-tensor components of the density matrix for the 2+ state of the 24Mg nucleus at 1.369 MeV were reconstructed, and its orientation properties were determined. These experimental results were compared with the results of calculations based on various versions of the coupled-channel method.

Populations of sublevels 24Mg(2+) nucleus formed in the reaction 24Mg(d, d1γ)24Mg at Ed = 15.3 MeV

Angular dependences of density matrix spin tensors and sublevel populations are experimentally reconstructed for the 24Mg(2+, 1.369 MeV) nucleus formed in the inelastic scattering of deuterons by 24Mg at Ed = 15.3 MeV and deuteron emission angles from 25° to 165° (lab). The experimental results are compared to those from calculations using different versions of the coupled-channel method.

Correlation features of the reaction 9Be(d, pγ)10Be at Ed=15.3 MeV and structure of the 10Be nucleus

Double-differential cross sections for the reaction 9Be(d, pγ)10Be at Ed=15.3 MeV are measured for proton emission into the forward hemisphere. All even spin-tensor components of the density matrix for the 2+ 3.37-MeV state of the residual nucleus are reconstructed in a model-independent way. The angular distributions of the populations of the magnetic substates and of the tensors of the angular-momentum orientation for the state in question are also obtained. The experimental results are compared with the results of the calculations performed by the coupled-channel method under the assumption of the neutron-stripping mechanism. The calculated correlation features are found to be highly sensitive to the wave functions for the participant nuclei, especially the 10Be nucleus. The importance of taking into account multistep processes in the reaction being considered is demonstrated.

Investigation of αγ angular correlations in the reaction 15N(p, αγ)12C induced by 7.5-MeV protons

The double-differential cross sections for the reaction 15N(p, αγ)12C induced by 7.5-MeV protons are measured for alpha-particle emission angles from 20° to 160°. All even spin-tensor components of the density matrix for the 2+ state (4.44 MeV) of the final nucleus are reconstructed by a model-independent method. For the same state of the carbon nucleus, the populations of magnetic sublevels and the components of the angular-momentum-orientation tensor are analyzed as functions of the alpha-particle emission angle. Our experimental data are compared with theoretical predictions based on the triton-cluster-pickup mechanism treated within the coupled-channel method. It is shown that correlation features are sensitive to the reaction mechanism and to structural characteristics of the nuclei involved. The role of sequential processes is emphasized.

Angular correlations in 24Mg(p, pγ)24Mg inelastic scattering at Ep = 7.4 MeV

Double differential cross sections of the reaction 24Mg(p, pγ1.369)24Mg at Ep = 7.4 MeV are measured for proton emission angles of 30°–160° (lab.). All odd components of the density matrix spin-tensors of the 24Mg nucleus in the 2+ (1.369 MeV) state are restored and all its orientation characteristics are determined. The experimental results are compared to calculation results using the coupled channel method and assuming of the formation of resonance in the 25Al compound nucleus.

Tensor features and dynamical deformation of the 24Mg(2+) nucleus in the reaction 24Mg(d, dγ)24Mg at Ed = 15.3 MeV

The results obtained by reconstructing of the experimental angular dependences of polarization tensors, the tensors of orientation of multipole moments, and the dynamical deformation of 24Mg nuclei produced in the 2+ state at 1.369 MeV in inelastic deuteron scattering on 24Mg nuclei at Ed = 15.3 MeV for deuteron scattering angles between 25° and 165° in the laboratory frame are presented. The experimental results are compared with the results of calculations based on various versions of the coupled-channel method. The role of spin-orbit and tensor d24Mg interactions is discussed along with the influence of the reorientation effect. The correlation features of the 2+ state of the 24Mg nucleus at 1.369 MeV that were determined in inelastic deuteron and alpha-particle scattering on 24Mg are compared.

Investigation of the inelastic deuteron scattering mechanism for 24 Mg at E d = 15.3 MeV

Results from measuring the angular dependence of differential cross sections of elastic and inelastic deuteron scattering by the 24Mg nucleus with the formation of the ground and first excited states 2+, 1.369 MeV at Ed = 15.3 MeV for deuteron angles interval from 21.5° to 161.5° (lab) are presented. Experimental results are compared with calculations in various approximations of the coupled channels model. The influence of heavy particle stripping mechanisms and consecutive particle transfer is also discussed.

Tensor polarization of {sup 12}C(2{sup +}), {sup 24}Mg(2{sup +}), and {sup 28}Si(2{sup +}) oriented nuclei

Measured and calculated angular dependences of components of the polarization tensor of a 12C nucleus in the 2+ state at 4.44 MeV formed in various reactions involving light particles, as well as 24Mg(2+, 1.369 MeV) and 28Si(2+, 1.78 MeV) nuclei formed in inelastic alpha-particle scattering, are presented. The experimental tensor polarization in question was reconstructed on the basis of the densitymatrix spin-tensors found previously for these nuclei. The parameters of the quadrupole and hexadecapole orientation of the nuclei under study were obtained. The experimental polarization features were compared with the results of calculations based on the coupled-channel method. Special features of the behavior of tensor polarizations in various reactions were discussed. The similarity of the experimental angular dependences of the components of tensor polarizations in inelastic deuteron and 3He scattering on 12C nuclei, as well as in inelastic alpha-particle scattering on 24Mg and 28Si nuclei, was demonstrated.Measured and calculated angular dependences of components of the polarization tensor of a {sup 12}C nucleus in the 2{sup +} state at 4.44 MeV formed in various reactions involving light particles, as well as {sup 24}Mg(2{sup +}, 1.369 MeV) and {sup 28}Si(2{sup +}, 1.78 MeV) nuclei formed in inelastic alpha-particle scattering, are presented. The experimental tensor polarization in question was reconstructed on the basis of the densitymatrix spin-tensors found previously for these nuclei. The parameters of the quadrupole and hexadecapole orientation of the nuclei under study were obtained. The experimental polarization features were compared with the results of calculations based on the coupled-channel method. Special features of the behavior of tensor polarizations in various reactions were discussed. The similarity of the experimental angular dependences of the components of tensor polarizations in inelastic deuteron and {sup 3}He scattering on {sup 12}C nuclei, as well as in inelastic alpha-particle scattering on {sup 24}Mg and {sup 28}Si nuclei, was demonstrated.