Proton inelastic scatterings from several s-d shell nuclei are analyzed using optical potential model and collective model in Dirac coupled channel formalism. The optical potential parameters obtained phenomenological...Proton inelastic scatterings from several s-d shell nuclei are analyzed using optical potential model and collective model in Dirac coupled channel formalism. The optical potential parameters obtained phenomenologically for the scatterings from the s-d shell nuclei are compared with each other for systematic Dirac analysis. Dirac equations are reduced to the second-order differential equations in order to obtain the Schroedinger equivalent effective central and spin-orbit optical potentials, and the surface-peaked phenomena are observed at the real effective central potentials for the scatterings from 22Ne, 20Ne and 24Mg. By analyzing the obtained effective spin-orbit potentials, it is confirmed that the spin-orbit interaction is a surface-peaked interaction. The first-order rotational collective models are used to describe the low-lying excited states of the ground state rotational bands in the s-d shell deformed nuclei, and the obtained deformation parameters are analyzed by comparing with each other, and compared with those obtained by using the nonrelativistic calculations. The obtained deformation parameters of Dirac phenomenological calculations for the s-d shell nuclei are found to agree pretty well with those of the nonrelativistic calculations using the same Woods-Saxon potential shape, even though the theoretical bases are quite different.展开更多
This study presents a combined experimental and theoretical investigation of the^(6)Li+^(12)C nuclear reaction at a laboratory energy of 68 MeV.The reaction products are identified via the standard△E–E technique.Ang...This study presents a combined experimental and theoretical investigation of the^(6)Li+^(12)C nuclear reaction at a laboratory energy of 68 MeV.The reaction products are identified via the standard△E–E technique.Angular distributions are constructed for the elastic,inelastic,and deuteron transfer channels by detecting emitted particles–^(6)Li andα.Elastic and inelastic scattering of^(6)Li off^(12)C are analyzed using the optical model and coupled channels approaches,with the interaction described by a double-folding potential.This potential is calculated based on the three-body wave function of^(6)Li.Pronounced coupled-channel effects that modify the potential and allow accurate reproduction of the experimental cross sections are observed.The resulting polarized potentials provide a more precise description of the initial-state interaction for further reaction modeling.The deuteron transfer channel,^(12)C(^(6)Li,α)^(14)N,is studied using the coupled reaction channels method.The coupling between the transfer and elastic channels is implemented using the three-body wave function of^(6)Li.As an alternative,a regular wave function constructed with a phenomenological Woods–Saxon potential is also employed.Comparison between the calculated differential cross sections and experimental data reveals a more complex and nuanced reaction mechanism,which supports the cluster structure of^(6)Li.展开更多
The new measured data of elastic and inelastic 20Ne+130Te scattering at an energy of 15.3 A MeV are analyzed in framework of the nuclear optical potential.Three types of semi-microscopic potentials are used:the real p...The new measured data of elastic and inelastic 20Ne+130Te scattering at an energy of 15.3 A MeV are analyzed in framework of the nuclear optical potential.Three types of semi-microscopic potentials are used:the real part is calculated using a double folding model in conjunction with the conventional phenomenological Woods-Saxon(WS)potential for the imaginary part.Two real cluster models are constructed using the cluster structure of^(20)Ne nucleus as 5αandα+^(16)O.The real part of the third potential is generated using a CDM3Y6 interaction employed for comparison.Three excited energies to the superposition of the projectile and target states,ground-state(Quasi),1.6 and 2.5 MeV are investigated using deformed potentials.The contributions of these states are calculated using a one-step distorted wave Born approximation and coupled Channels approaches.Successful calculations and results using semi-microscopic potentials in simple one-channel and coupled channels are obtained.The values of cross section and volume integrals require more contributions to enable more comparisons regarding this project.展开更多
In this work, Rotation model and rotation vibration coupled channel optical model (CCOM) were first used to carry out systematic calculation of neutron direct inelastic scattering cross section (DISCS) for the reacti...In this work, Rotation model and rotation vibration coupled channel optical model (CCOM) were first used to carry out systematic calculation of neutron direct inelastic scattering cross section (DISCS) for the reaction 238 U (n,n′) with an incident energy from 0 01 MeV to 20 0 MeV . The number of coupled energy levels involved in this calculation increased to eight at the first time, namely 0 +, 2 +, 4 +, 6 +, 8 + in the ground rotation band of 238 U and 1 -, 3 -, 5 - in the octupole vibration band with K=0 -. Some physical problems, such as how to get the optical model parameters of deformed nuclei and phonon amplitudes, are discussed.展开更多
To obtain the neutron spectroscopic amplitudes for 90-96Zx overlaps experimental data of elastic scatter-ing with small experimental errors and precise optical potentals were anary exin othe hiohpyecision o3D magnetic...To obtain the neutron spectroscopic amplitudes for 90-96Zx overlaps experimental data of elastic scatter-ing with small experimental errors and precise optical potentals were anary exin othe hiohpyecision o3D magneticangular distributions of^12,^13C+^AZr(A=90,91,92,94,96)were measured using the high-precision Q3D magnetic spectrometer in the Tandem accelerator.The Sao Paulo potential was used for the optical potential.The optical mod-el and coupled channel calculations were compared with the experimental data.The theoretical results were found tobe very close to the experimental data.In addition,the possible effects of the couplings to the inelastic channels of the^AZr targets and 12,13^C projectiles on the elastic scattering were studied.It was observed that the couplings to the in-elastic channels of the^12,^13C projectiles could improve the agreement with the experimental data,while the inelasticcouplings to the target states are of minor importance.The effect of the one-neutron stripping in the^13C+^AZr elasticscattering was also studied.The one-neutron stripping channel in^13C+^AZr was found to be not relevant and did notaffect the elastic scattering angular distributions.Our results also show that in the reactions with the considered zir-conium isotopes,the presence of the extra neutron in^13C does not influence the reaction mechanism,which is gov-erned by the collective excitation of the^12C core.展开更多
文摘Proton inelastic scatterings from several s-d shell nuclei are analyzed using optical potential model and collective model in Dirac coupled channel formalism. The optical potential parameters obtained phenomenologically for the scatterings from the s-d shell nuclei are compared with each other for systematic Dirac analysis. Dirac equations are reduced to the second-order differential equations in order to obtain the Schroedinger equivalent effective central and spin-orbit optical potentials, and the surface-peaked phenomena are observed at the real effective central potentials for the scatterings from 22Ne, 20Ne and 24Mg. By analyzing the obtained effective spin-orbit potentials, it is confirmed that the spin-orbit interaction is a surface-peaked interaction. The first-order rotational collective models are used to describe the low-lying excited states of the ground state rotational bands in the s-d shell deformed nuclei, and the obtained deformation parameters are analyzed by comparing with each other, and compared with those obtained by using the nonrelativistic calculations. The obtained deformation parameters of Dirac phenomenological calculations for the s-d shell nuclei are found to agree pretty well with those of the nonrelativistic calculations using the same Woods-Saxon potential shape, even though the theoretical bases are quite different.
基金Funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan(AP19677087)。
文摘This study presents a combined experimental and theoretical investigation of the^(6)Li+^(12)C nuclear reaction at a laboratory energy of 68 MeV.The reaction products are identified via the standard△E–E technique.Angular distributions are constructed for the elastic,inelastic,and deuteron transfer channels by detecting emitted particles–^(6)Li andα.Elastic and inelastic scattering of^(6)Li off^(12)C are analyzed using the optical model and coupled channels approaches,with the interaction described by a double-folding potential.This potential is calculated based on the three-body wave function of^(6)Li.Pronounced coupled-channel effects that modify the potential and allow accurate reproduction of the experimental cross sections are observed.The resulting polarized potentials provide a more precise description of the initial-state interaction for further reaction modeling.The deuteron transfer channel,^(12)C(^(6)Li,α)^(14)N,is studied using the coupled reaction channels method.The coupling between the transfer and elastic channels is implemented using the three-body wave function of^(6)Li.As an alternative,a regular wave function constructed with a phenomenological Woods–Saxon potential is also employed.Comparison between the calculated differential cross sections and experimental data reveals a more complex and nuanced reaction mechanism,which supports the cluster structure of^(6)Li.
文摘The new measured data of elastic and inelastic 20Ne+130Te scattering at an energy of 15.3 A MeV are analyzed in framework of the nuclear optical potential.Three types of semi-microscopic potentials are used:the real part is calculated using a double folding model in conjunction with the conventional phenomenological Woods-Saxon(WS)potential for the imaginary part.Two real cluster models are constructed using the cluster structure of^(20)Ne nucleus as 5αandα+^(16)O.The real part of the third potential is generated using a CDM3Y6 interaction employed for comparison.Three excited energies to the superposition of the projectile and target states,ground-state(Quasi),1.6 and 2.5 MeV are investigated using deformed potentials.The contributions of these states are calculated using a one-step distorted wave Born approximation and coupled Channels approaches.Successful calculations and results using semi-microscopic potentials in simple one-channel and coupled channels are obtained.The values of cross section and volume integrals require more contributions to enable more comparisons regarding this project.
文摘In this work, Rotation model and rotation vibration coupled channel optical model (CCOM) were first used to carry out systematic calculation of neutron direct inelastic scattering cross section (DISCS) for the reaction 238 U (n,n′) with an incident energy from 0 01 MeV to 20 0 MeV . The number of coupled energy levels involved in this calculation increased to eight at the first time, namely 0 +, 2 +, 4 +, 6 +, 8 + in the ground rotation band of 238 U and 1 -, 3 -, 5 - in the octupole vibration band with K=0 -. Some physical problems, such as how to get the optical model parameters of deformed nuclei and phonon amplitudes, are discussed.
基金Supported by National Natural Science Foundation of China(U1832130,11975040 and 11475013)National Key R&D Program of China(2017YFF0106501)Brazilian financial support from CNPq,CAPES and FAPERJ and from INCT-FNA(Instituto Nacional de Ciência e Tecnologia-Física Nuclear e Aplicações)(464898/2014-5)。
文摘To obtain the neutron spectroscopic amplitudes for 90-96Zx overlaps experimental data of elastic scatter-ing with small experimental errors and precise optical potentals were anary exin othe hiohpyecision o3D magneticangular distributions of^12,^13C+^AZr(A=90,91,92,94,96)were measured using the high-precision Q3D magnetic spectrometer in the Tandem accelerator.The Sao Paulo potential was used for the optical potential.The optical mod-el and coupled channel calculations were compared with the experimental data.The theoretical results were found tobe very close to the experimental data.In addition,the possible effects of the couplings to the inelastic channels of the^AZr targets and 12,13^C projectiles on the elastic scattering were studied.It was observed that the couplings to the in-elastic channels of the^12,^13C projectiles could improve the agreement with the experimental data,while the inelasticcouplings to the target states are of minor importance.The effect of the one-neutron stripping in the^13C+^AZr elasticscattering was also studied.The one-neutron stripping channel in^13C+^AZr was found to be not relevant and did notaffect the elastic scattering angular distributions.Our results also show that in the reactions with the considered zir-conium isotopes,the presence of the extra neutron in^13C does not influence the reaction mechanism,which is gov-erned by the collective excitation of the^12C core.
