Calculation of Fission Fragment Angular Anisotropy in Heavy-Ion Induced Fission

Khamehchi

2010

Phys. Rev. C

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Compound nucleus spin distribution has been calculated for several fission reaction systems induced by nucleons and heavy ions. Determination of the spin distribution for these systems is based upon the comparison between the experimental data of the fission fragment angular distributions as well as the prediction of the standard saddle-point statistical model (SSPSM). For the systems, the two cases, namely with and without neutron emission corrections were considered. This method is used for the first time to determine compound nucleus spin distribution. Afterwards, our theoretical results have been compared with the data obtained from the coupled-channel technique as well as the Wong model, and satisfactory agreements were found. Furthermore, we have introduced a semiclassical approximation relation for the compound nucleus spin distribution of these systems.

Section: Fission Fragment Angular Distribution Methodsmentioning

confidence: 99%

Calculation of spin distribution for several fission reaction systems induced by nucleons and heavy ions

Khamehchi

2010

Phys. Rev. C

Self Cite

“…respectively. The dashed line is the calculated ℑ ef f for the system by considering correction related to the average number of emitted neutrons [10].…”

mentioning

confidence: 99%

Effective moment of inertia for several fission reaction systems induced by nucleons, light particles, and heavy ions

2011

Phys. Rev. C

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Compound nucleus effective moment of inertia has been calculated for several fission reaction systems induced by nucleons, light particles, and heavy ions. Determination of this quantity for these systems is based upon the comparison between the experimental data of the fission fragment angular distributions as well as the prediction of the standard saddle-point statistical model (SSPSM). For the systems, the two cases, namely with and without neutron emission corrections were considered. In these calculations, it is assumed that all the neutrons are emitted before reaching the saddle point.It should be noted that the above method for determining of the effective moment of inertia had not been reported until now and this method is used for the first time to determine compound nucleus effective moment of inertia. Hence, our calculations are of particular importance in obtaining this quantity, and have a significant rule in the field of fission physics.Afterwards, our theoretical results have been compared with the data obtained from the rotational liquid drop model as well as the Sierk model, and satisfactory agreements were found. Finally, we have considered the effective moment of inertia of compound nuclei for the systems that formed similar compound nuclei at similar excitation energies.

Effect of the energy spectrum and angular momentum of pre-scission neutrons on the prediction of fission fragment angular anisotropy by the models

Khanlari

2016

Int. J. Mod. Phys. E

Effects of the various neutron emission energy spectra, as well as the influence of the angular momentum of pre-scission neutrons on theoretical predictions of fission fragment angular anisotropies for several heavy-ion induced fission systems are considered. Although theoretical calculations of angular anisotropy are very sensitive to neutron emission correction, the effects of the different values of kinetic energy of emitted neutrons derived from the various neutron emission energy spectra before reaching to the saddle point on the prediction of fission fragment angular distribution by the model are not significant and can be neglected, since these effects on angular anisotropies of fission fragments for a wide range of fissility parameters and excitation energies of compound nuclei are not more than 10%. Furthermore, the theoretical prediction of fission fragment angular anisotropy is not sensitive to the angular momentum of emitted neutrons.