Comparison of fission barrier and level density models for (α,f) reaction of some heavy nuclei

2014 ◽  
Vol 70 ◽  
pp. 175-179 ◽  
Author(s):  
İsmail H. Sarpün ◽  
Abdullah Aydın ◽  
Abdullah Kaplan ◽  
Hülya Koca ◽  
Eyyüp Tel
Keyword(s):  
Level Density ◽  
Fission Barrier ◽  
Heavy Nuclei ◽  
Level Density Models

An investigation of effects of level density models and gamma ray strength functions on cross-section calculations for the production of 90Y, 153Sm, 169Er, 177Lu and 186Re therapeutic radioisotopes via (n,γ) reactions

2019 ◽  
Vol 108 (1) ◽  
pp. 11-17
Author(s):  
Mert Şekerci ◽  
Hasan Özdoğan ◽  
Abdullah Kaplan
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Production Cross Section ◽  
Gamma Ray ◽  
Production Cross ◽  
Level Density ◽  
Experimental Studies ◽  
Level Density Models ◽  
Strength Functions ◽  
Cancer Diseases

Abstract One of the methods used to treat different cancer diseases is the employment of therapeutic radioisotopes. Therefore, many clinical, theoretical and experimental studies are being carried out on those radioisotopes. In this study, the effects of level density models and gamma ray strength functions on the theoretical production cross-section calculations for the therapeutic radioisotopes 90Y, 153Sm, 169Er, 177Lu and 186Re in the (n,γ) route have been investigated. TALYS 1.9 code has been used by employing different level density models and gamma ray strength functions. The theoretically obtained data were compared with the experimental data taken from the literature. The results are presented graphically for better interpretation.

THE FISSION BARRIERS OF HEAVY AND EXOTIC NUCLEI

2010 ◽  
Vol 19 (04) ◽  
pp. 514-520 ◽  
Author(s):  
FEDIR IVANYUK ◽  
KRZYSZTOF POMORSKI
Keyword(s):  
Liquid Drop ◽  
Optimal Shape ◽  
Exotic Nuclei ◽  
Fission Barrier ◽  
Heavy Nuclei ◽  
Accurate Approximation ◽  
Barrier Heights ◽  
A Value ◽  
Fission Barriers ◽  
Experimental Values

We have calculated the liquid drop fission barriers of medium and heavy nuclei within the Lublin-Strasbourg-Drop model. Exploiting in addition the topographical theorem by Myers and Światecki we propose a simple but quite accurate approximation of the fission barrier heights. When comparing the r.m.s. deviation of approximated versus experimental values of fission barrier heights for known nuclei with Z > 70 a value 1.1 MeV is obtained which is comparable with the experimental uncertainties. The Strutinsky optimal shape method is generalized to the left-right asymmetric shapes of nuclei in order to investigate the influence of this degree of freedom on the barrier heights.

scholarly journals Calculations of (γ,n) Reaction Cross Sections using Different Level Density Models for Some Lanthanide Nuclei

2015 ◽  
Vol 128 (2B) ◽  
pp. B-228-B-231 ◽  
Author(s):  
U. Akçaalan ◽  
R. Ünal ◽  
İ.H. Sarpün ◽  
H.A. Yalim ◽  
B. Oruncak
Keyword(s):  
Cross Sections ◽  
Level Density ◽  
Reaction Cross ◽  
Level Density Models ◽  
Reaction Cross Sections

scholarly journals Gamma Strength Functions and Level Densities from High-Resolution Proton Scattering under 0°

2018 ◽  
Vol 178 ◽  
pp. 06002
Author(s):  
Peter von Neumann-Cosel ◽  
Sergej Bassauer ◽  
Dirk Martin ◽  
Atsushi Tamii
Keyword(s):  
High Resolution ◽  
Energy Region ◽  
Level Density ◽  
Experimental Information ◽  
Fluctuation Analysis ◽  
Proton Scattering ◽  
Heavy Nuclei ◽  
High Resolution Data ◽  
Dipole Resonance ◽  
Strength Functions

Inelastic proton scattering at energies of a few 100 MeV and forward angles including 0° provides a novel method to measure gamma strength functions (GSF) in nuclei in an energy range of about 5 – 20 MeV. The experiments provide not only the E1 but also the M1 part of the GSF. The latter is poorly known in heavy nuclei. Comparison with gamma decay data (e.g. from the Oslo method) allows to test the generalised Brink-Axel (BA) hypothesis in the energy region of the pygmy dipole resonance (PDR) crucial for the modelling of (n,γ) and (γ,n) reactions in astrophysical reaction networks. From the two test cases studied, 208Pb remains inconclusive in the energy region of the PDR because of large Porter-Thomas fluctuations due to the small level density (LD), while the BA hypothesis seems to hold in case of 96Mo. A fluctuation analysis of the high-resolution data also provides a direct measure of the LD in the energy region of the isovector giant dipole resonance (IVGDR) well above the neutron threshold, where hardly any experimental information is available. This permits an independent test of the decomposition of GSF and LD in Oslo-type experiments.

scholarly journals FURTHER MICROSCOPIC STUDIES OF THE FISSION BARRIERS OF HEAVY NUCLEI

2012 ◽  
Vol 21 (05) ◽  
pp. 1250051 ◽  
Author(s):  
T. V. NHAN HAO ◽  
J. LE BLOAS ◽  
MENG-HOCK KOH ◽  
L. BONNEAU ◽  
P. QUENTIN
Keyword(s):  
Spontaneous Fission ◽  
The Self ◽  
Fission Barrier ◽  
Heavy Nuclei ◽  
Barrier Heights ◽  
Fission Barriers ◽  
Self Consistent ◽  
Microscopic Studies ◽  
Mean Fields ◽  
Approximate Treatment

Two systematic sources of error in most current microscopic evaluations of fission-barrier heights are studied. They are concerned with an approximate treatment of the Coulomb exchange terms (known as the Slater approximation) in the self-consistent mean-fields and the projection on good parity states (e.g., of positive parity for the spontaneous fission of an even–even nucleus) of left–right reflection asymmetric intrinsic solutions (e.g., around the second barrier). Approximate or unprojected solutions are shown to lead each to an underestimation of the barrier heights by a few hundred keV.

Level density model effects on the production cross-section calculations of some medical isotopes via (α, xn) reactions where x = 1–3

2020 ◽  
Vol 35 (24) ◽  
pp. 2050202
Author(s):  
Mert Şekerci ◽  
Hasan Özdoğan ◽  
Abdullah Kaplan
Keyword(s):  
Cross Section ◽  
Production Cross Section ◽  
Nuclear Reactions ◽  
Theoretical Calculations ◽  
Production Cross ◽  
Level Density ◽  
Medical Application ◽  
Density Model ◽  
Level Density Models ◽  
Theoretical Results

Level density models have an undeniable importance for a better perception on the nature of nuclear reactions, which influences our life via various ways. Many novel and advanced medical application use radioisotopes, which are produced with nuclear reactions. By considering the connection between the level density models and the importance of theoretical calculations for the production routes of medically important isotopes, this study is performed to investigate the level density model effects on the production cross-section calculations of [Formula: see text]Zn, [Formula: see text]Ga, [Formula: see text]Kr, [Formula: see text]Pd, [Formula: see text]In, [Formula: see text]I and [Formula: see text]At radioisotopes via some alpha particle induced and neutron emitting reactions. For theoretical calculations; frequently used computation tools, such as TALYS and EMPIRE codes, are applied. Obtained theoretical results are then compared with the experimental data, taken from Experimental Nuclear Reaction Data (EXFOR) library. For a better interpretation of the results, a mean weighted deviation calculation for each investigated reaction is performed in addition to a visual comparison of the graphical representations of the outcomes.

The (n,γ) reaction productions of 35S, 42Ar, 45Ca, 63Ni, 85Kr, 89Sr, 113mCd, 121m,123Sn, 147Pm, 151Sm, 152,154,155Eu, 170,171Tm, 185,188W, 194Os, 204Tl, 210Po, 227Ac, 242,244Cm radioisotopes for using in nuclear battery via phenomenological and microscopic level density models

2019 ◽  
Vol 28 (08) ◽  
pp. 1950057 ◽  
Author(s):  
Ozan Artun
Keyword(s):  
Cross Section ◽  
Level Density ◽  
Nuclear Data ◽  
Microscopic Level ◽  
Level Density Models ◽  
Battery Technology ◽  
Reaction Processes ◽  
Nuclear Battery ◽  
Induced Reaction

Aims of this work are: (i) Investigation of the production of some radioisotopes that could be used in nuclear battery technology with neutron-induced reaction processes, (ii) Estimation of the cross-section curves of [Formula: see text] reactions for astrophysical processes in the energy region between 1[Formula: see text]eV and 1[Formula: see text]MeV, (iii) Determination of suitable level density models for the [Formula: see text] reaction processes. Additionally, the obtained results were compared with the experimental data and recommended data. Based on the calculated results, to eliminate lack of nuclear data in the literature, we recommend new experiments for some reaction processes to be performed by the experimenters. Moreover, for the [Formula: see text] reaction processes, suitable level density models were proposed.

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