The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a 9Be target with a 3He beam at the incident energy of 30 MeV. Angular distributions for 9Be(3He, 3He) 9Be, 9Be (3He, ...The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a 9Be target with a 3He beam at the incident energy of 30 MeV. Angular distributions for 9Be(3He, 3He) 9Be, 9Be (3He, 3He) 8Be, 9Be (3He, 7Be) 5He, 9Be (3He, 6Li) 6Li and 9Be (3He, 7Li) 5Li reaction channels were measured. Experimental angular distributions for the corresponding ground states (g.s.) were analyzed within the framework of the optical model, the coupled-channel approach and the distorted-wave Born approximation. Cross sections for channels leading to unbound 5Heg.s., 5Lig.s. and 8Be systems were obtained from singles measurements where the relationship between the energy and the scattering angle of the observed stable ejectile was constrained by two-body kinematics. Information on the cluster structure of 9Be was obtained from the transfer channels. It was concluded that cluster transfer was an important mechanism in the investigated nuclear reaction channels. In the present work an attempt was made to estimate the relative strengths of the interesting (n + 8Be) and (α + 5He) cluster configurations in 9Be. The contributions of different exit channels have been determined confirming that the (α + 5He) configuration plays an important role. The configuration of 8Be consisting of two bound helium clusters (5He + 6He) is significantly suppressed, whereas the two-body configurations (n + 8Be) and (α + 5He) including unbound 8Be and 5He are found more probable.展开更多
This paper presents the results of experiments conducted to measure the cross-sections for elastic scattering and nucleon transfer channels in the ^(6)Li+^(9)Be reaction at an incident energy of 68 MeV:^(9)Be(^(6)Li,^...This paper presents the results of experiments conducted to measure the cross-sections for elastic scattering and nucleon transfer channels in the ^(6)Li+^(9)Be reaction at an incident energy of 68 MeV:^(9)Be(^(6)Li,^(6)Li)^(9)Be,^(9)Be(^(6)Li,7Li)8Be,^(9)Be(^(6)Li,7Li)^(8)Be_(2+),^(9)Be(^(6)Li,^(8)Li)^(7)Be,and ^(9)Be(^(6)Li,^(7)Be)^(8)Li.The objective of the study is to elucidate the manifestation of the cluster structure of ^(9)Be.Theoretical analysis of the contributions of the one-step and two-step neutron transfer mechanisms is performed using the distorted wave Born approximation method with the Fresco code.Good agreement between the calculations and the experimental data is obtained for the channels of elastic scattering ^(9)Be(^(6)Li,^(6)Li)^(9)Be,neutron ^(9)Be(^(6)Li,^(7)Li)^(8)Be,and proton transfer ^(9)Be(^(6)Li,^(7)Be)^(8)Li,as well as for the transfer of two neutrons ^(9)Be(^(6)Li,^(8)Li)^(7)Be.The dineutron cluster transfer mechanism makes a dominant contribution to the ^(9)Be(^(6)Li,^(8)Li)^(7)Be reaction channel at forward angles.展开更多
The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are presented.The measurements were performed using the high-resolution magnetic analyzer MAVR with beams of ^...The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are presented.The measurements were performed using the high-resolution magnetic analyzer MAVR with beams of ^(48)Ca(280 MeV)and ^(56)Fe(320 and 400 MeV)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation approach.An analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.展开更多
基金supported in part by the Russian Foundation for Basic Research(project numbers:13-02-00533 and 14-02-91053),the CANAM(IPN ASCR)by the grants to JINR(Dubna)from the Czech Republic,the Republic of Poland and the mobility grant from the Academy of Finland.
文摘The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a 9Be target with a 3He beam at the incident energy of 30 MeV. Angular distributions for 9Be(3He, 3He) 9Be, 9Be (3He, 3He) 8Be, 9Be (3He, 7Be) 5He, 9Be (3He, 6Li) 6Li and 9Be (3He, 7Li) 5Li reaction channels were measured. Experimental angular distributions for the corresponding ground states (g.s.) were analyzed within the framework of the optical model, the coupled-channel approach and the distorted-wave Born approximation. Cross sections for channels leading to unbound 5Heg.s., 5Lig.s. and 8Be systems were obtained from singles measurements where the relationship between the energy and the scattering angle of the observed stable ejectile was constrained by two-body kinematics. Information on the cluster structure of 9Be was obtained from the transfer channels. It was concluded that cluster transfer was an important mechanism in the investigated nuclear reaction channels. In the present work an attempt was made to estimate the relative strengths of the interesting (n + 8Be) and (α + 5He) cluster configurations in 9Be. The contributions of different exit channels have been determined confirming that the (α + 5He) configuration plays an important role. The configuration of 8Be consisting of two bound helium clusters (5He + 6He) is significantly suppressed, whereas the two-body configurations (n + 8Be) and (α + 5He) including unbound 8Be and 5He are found more probable.
基金Supported by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (AP19677087)by the Russian Science Foundation (24-22-00117)。
文摘This paper presents the results of experiments conducted to measure the cross-sections for elastic scattering and nucleon transfer channels in the ^(6)Li+^(9)Be reaction at an incident energy of 68 MeV:^(9)Be(^(6)Li,^(6)Li)^(9)Be,^(9)Be(^(6)Li,7Li)8Be,^(9)Be(^(6)Li,7Li)^(8)Be_(2+),^(9)Be(^(6)Li,^(8)Li)^(7)Be,and ^(9)Be(^(6)Li,^(7)Be)^(8)Li.The objective of the study is to elucidate the manifestation of the cluster structure of ^(9)Be.Theoretical analysis of the contributions of the one-step and two-step neutron transfer mechanisms is performed using the distorted wave Born approximation method with the Fresco code.Good agreement between the calculations and the experimental data is obtained for the channels of elastic scattering ^(9)Be(^(6)Li,^(6)Li)^(9)Be,neutron ^(9)Be(^(6)Li,^(7)Li)^(8)Be,and proton transfer ^(9)Be(^(6)Li,^(7)Be)^(8)Li,as well as for the transfer of two neutrons ^(9)Be(^(6)Li,^(8)Li)^(7)Be.The dineutron cluster transfer mechanism makes a dominant contribution to the ^(9)Be(^(6)Li,^(8)Li)^(7)Be reaction channel at forward angles.
文摘The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are presented.The measurements were performed using the high-resolution magnetic analyzer MAVR with beams of ^(48)Ca(280 MeV)and ^(56)Fe(320 and 400 MeV)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation approach.An analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.
