Dependence of Nucleon and Pion-Induced Fission Cross Sections on the Level Density Parameter in the Cascade-Exciton Model

Abstract Level density models have increasing importance to gain more in-depth into the nature of nuclear reactions. Many novel and advanced medical application use radioisotopes, which are produced with nuclear reactions. In this study, the effect of the level density parameters of the nucleus on the cross sections of neutron-fission reactions for 233U, 235U, 237U, 239U, 249Cf, 251Cf, 237Pu and 247Cm nuclei were investigated for up to 20 MeV neutrons. TALYS 1.8 software was used to calculate the cross-sections of neutron-fission reactions for different level density parameters. The calculations were compared with the EXFOR nuclear data library and the level density parameters, and the closest fit were searched. As outputs of the study, the effect of selection of level density parameter on cross section calculations was observed. The theoretically obtained data were compared with the experimental data taken from the literature. The results are presented graphically for better interpretation.

Download Full-text

The effect of deformation parameter of heavy nuclei on level density parameter

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v12i25.302 ◽

2019 ◽

Vol 12 (25) ◽

pp. 38-43

Author(s):

Mahdi Hadi Jasim

Keyword(s):

Cross Sections ◽

Collective Motion ◽

Level Density ◽

Reaction Cross ◽

Neutron Resonance ◽

Density Parameter ◽

Heavy Nuclei ◽

Nuclear Level Density ◽

S Wave ◽

Level Density Parameter

The possible effect of the collective motion in heavy nuclei has been investigated in the framework of Nilson model. This effect has been searched realistically by calculating the level density, which plays a significant role in the description of the reaction cross sections in the statistical nuclear theory. The nuclear level density parameter for some deformed radioisotopes of (even- even) target nuclei (Dy, W and Os) is calculated, by taking into consideration the collective motion for excitation modes for the observed nuclear spectra near the neutron binding energy. The method employed in the present work assumes equidistant spacing of the collective coupled state bands of the considered isotopes. The present calculated results for first excited rotational band have been compared with the accumulated values from the literature for s-wave neutron resonance data, and were in good agreement with those data.

Download Full-text

ALPHA PARTICLE INDUCED REACTIONS ON VANADIUM

International Journal of Modern Physics E ◽

10.1142/s0218301394000267 ◽

1994 ◽

Vol 03 (03) ◽

pp. 909-917

Author(s):

A.V. MOHAN RAO ◽

S.N. CHINTALAPUDI

Keyword(s):

Hybrid Model ◽

Cross Sections ◽

Alpha Particle ◽

Gamma Ray ◽

Level Density ◽

Spectroscopy Method ◽

Activation Technique ◽

Density Parameter ◽

Target Element ◽

Level Density Parameter

Alpha particle-induced reactions on the target element vanadium were investigated from threshold up to 55 MeV using the foil-stack activation technique and the Ge(Li) gamma ray spectroscopy method. Excitation functions for the formation of reaction residues 54Mn, 52Mn, 51Cr, 48V, 47Sc, 46Sc were investigated. The experimental cross-sections were compared with the predictions based on updated hybrid model (ALICE/90) using n0=4 (4p0h) and level density parameter a=A/9. A general agreement was found for all the reactions of (α, xn) type. However, the model failed badly in all cases of (α, zαxn) type of reactions.

Download Full-text

Effect of the Level Density Parameter Ratio on the Cross Sections of Fission of Uranium Isotopes

Acta Physica Polonica A ◽

10.12693/aphyspola.130.306 ◽

2016 ◽

Vol 130 (1) ◽

pp. 306-308 ◽

Cited By ~ 2

Author(s):

N. Karpuz

Keyword(s):

Cross Sections ◽

Level Density ◽

Uranium Isotopes ◽

Density Parameter ◽

Level Density Parameter ◽

Parameter Ratio ◽

The Cross

Download Full-text

Analysis of n-evaporation from light mass nuclei formed via p-induced reactions

Modern Physics Letters A ◽

10.1142/s0217732320500820 ◽

2020 ◽

Vol 35 (11) ◽

pp. 2050082

Author(s):

Amandeep Kaur ◽

Manoj K. Sharma

Keyword(s):

Proton Beam ◽

Cross Sections ◽

Level Density ◽

Incident Beam ◽

Mass Region ◽

Cluster Decay ◽

Compound System ◽

Density Parameter ◽

Relative Role ◽

Level Density Parameter

This work deals with the decay analysis of three compound nuclei [Formula: see text], [Formula: see text] and [Formula: see text] formed in proton-induced reactions [Formula: see text], [Formula: see text] and [Formula: see text] at incident beam energies of 1–5 MeV using the Dynamical Cluster-decay Model (DCM). The motive is to explore the decay of compound systems formed via light charged particles as projectiles. The experimentally available data of n-evaporation for the aforementioned systems are addressed by optimizing the neck-length parameter [Formula: see text], using spherical fragmentation approach. The comparative analysis of the decay structure of the chosen systems is carried out at a common incident beam energy [Formula: see text] MeV. The effect of angular momentum [Formula: see text] and quadrupole [Formula: see text]-deformations is explored in reference to the decay structure/fragmentation of compound systems. In addition to this, the sensitivity of DCM-based cross-sections toward level density parameter (LDP) [Formula: see text] is also analyzed. The relative role of mass-dependent level density parameter [Formula: see text] is also investigated for compound systems belonging to light and heavy mass region. Lastly, a theoretical systematics is explored where the proton beam in the reaction [Formula: see text] is replaced by a neutron beam forming the compound system [Formula: see text], having the same [Formula: see text], but [Formula: see text] one less than that of the compound system formed in the reaction using proton beam, and its effect on the decay characteristics such as preformation probability, penetration probability and barrier height is analyzed.

Download Full-text