Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The error information from the recent measurements of the fission cross section ratios of nine isotopes, 23°Th, 232Th, 233U, 234U, 236U, 238U, 237Np, 239Pu, and 242Pu, relative to 235U at 14.74 MeV neutron energy was used to calculate their correlations. The remaining 36 non-trivial and non-reciprocal cross section ratios and their errors were determined and compared to evaluated (ENDF/B-V) values. There are serious differences but it was concluded that the reduction of three of the evaluated cross sections would remove most of them. The cross sections to be reduced are 23°Th - 13%, 237Np - 9.6% and 239Pu - 7.6%. 5 refs., 6 tabs.
The Fission Cross Section Ratios and Error Analysis for Ten Thorium, Uranium, Neptunium and Plutonium Isotopes at 14. 74 MeV Neutron Energy
Physics Briefs
The Fission Cross Sections of 23°Th, 232Th, 233U, 234U, 236U, 238U, 237Np, 239Pu and 242Pu Relative 235U at 14. 74 MeV Neutron Energy
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The measurement of the fission cross section ratios of nine isotopes relative to 235U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for 235U are: 23°Th - 0.290 +- 1.9%; 232Th - 0.191 +- 1.9%; 233U - 1.132 +- 0.7%; 234U - 0.998 +- 1.0%; 236U - 0.791 +- 1.1%; 238U - 0.587 +- 1.1%; 237Np - 1.060 +- 1.4%; 239Pu - 1.152 +- 1.1%; 242Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The measurement of the fission cross section ratios of nine isotopes relative to 235U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for 235U are: 23°Th - 0.290 +- 1.9%; 232Th - 0.191 +- 1.9%; 233U - 1.132 +- 0.7%; 234U - 0.998 +- 1.0%; 236U - 0.791 +- 1.1%; 238U - 0.587 +- 1.1%; 237Np - 1.060 +- 1.4%; 239Pu - 1.152 +- 1.1%; 242Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs.
Nuclear Science Abstracts
The Fission Cross Sections of Some Thorium, Uranium, Neptunium and Plutonium Isotopes Relative to 235U
Passive Nondestructive Assay of Nuclear Materials
Author: Doug Reilly
Publisher:
ISBN: 9780160327247
Category : Non-destructive testing
Languages : en
Pages : 700
Book Description
Publisher:
ISBN: 9780160327247
Category : Non-destructive testing
Languages : en
Pages : 700
Book Description
Neutron Fission of 235,237,239U and 241,243Pu
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 14
Book Description
In a recent paper submitted to Phys. Rev. C they have presented estimates for (n, f) cross sections on a series of Thorium, Uranium and Plutonium isotopes over the range E{sub n} = 0.1-2.5 MeV. The (n, f) cross sections for many of these isotopes are difficult or impossible to measure in the laboratory. The cross sections were obtained from previous (t, pf) reaction data invoking a model which takes into account the differences between (t, pf) and (n, f) reaction processes, and which includes improved estimates for the neutron compound formation process. The purpose of this note is: (1) to compare the estimated cross sections to current data files in both ENDF and ENDL databases; (2) to estimate ratios of cross sections relatively to 235U integrated over the ''tamped flattop'' critical assembly spectrum that was used in the earlier 237U report; and (3) to show the effect on the integral cross sections when the neutron capturing state is an excited rotational state or an isomer. The isomer and excited state results are shown for 235U and 237U.
Publisher:
ISBN:
Category :
Languages : en
Pages : 14
Book Description
In a recent paper submitted to Phys. Rev. C they have presented estimates for (n, f) cross sections on a series of Thorium, Uranium and Plutonium isotopes over the range E{sub n} = 0.1-2.5 MeV. The (n, f) cross sections for many of these isotopes are difficult or impossible to measure in the laboratory. The cross sections were obtained from previous (t, pf) reaction data invoking a model which takes into account the differences between (t, pf) and (n, f) reaction processes, and which includes improved estimates for the neutron compound formation process. The purpose of this note is: (1) to compare the estimated cross sections to current data files in both ENDF and ENDL databases; (2) to estimate ratios of cross sections relatively to 235U integrated over the ''tamped flattop'' critical assembly spectrum that was used in the earlier 237U report; and (3) to show the effect on the integral cross sections when the neutron capturing state is an excited rotational state or an isomer. The isomer and excited state results are shown for 235U and 237U.
Fission Cross Sections of Thorium 232, Uranium 233, 235 and 236, Plutonium 239 Relative to Uranum 238 for 14 MeV Neutrons
Author: Warren Nyer
Publisher:
ISBN:
Category : Cross sections (Nuclear physics)
Languages : en
Pages : 18
Book Description
Publisher:
ISBN:
Category : Cross sections (Nuclear physics)
Languages : en
Pages : 18
Book Description
Evaluation of Fission Cross Sections and Covariances 233U, 235U, 238U, 239Pu, 240Pu, and 241Pu
Author:
Publisher:
ISBN:
Category : Cross sections (Nuclear physics)
Languages : en
Pages : 88
Book Description
Publisher:
ISBN:
Category : Cross sections (Nuclear physics)
Languages : en
Pages : 88
Book Description
Measurements of Neutron-induced Fission Cross-section Ratios Involving Isotopes of Uranium and Plutonium. [0. 001 to 30 MeV, Cross Sections].
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A procedure, called the threshold cross section method was applied to our experimental data involving four uranium (233U 234U, 236U, and 238U) and five plutonium (239Pu, 24°Pu, 241Pu, 242Pu, and 244Pu) isotopes to determine ratios of fission cross sections relative to 235U. The data were gathered using ionization fission chambers and the time-of-flight technique at the LLL 100-MeV electron linear accelerator: measurements span the neutron energy range of 0.001 to 30 MeV. Experimental uncertainties common to past measurements were either eliminated or significantly reduced in this study by use of the threshold method, thereby making higher accuracies possible. The cross section ratios are absolute in the sense that they do not depend on the work of others. Results from our ratios involving 233U, 235U, 238U, and 239Pu are used to illustrate this method.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A procedure, called the threshold cross section method was applied to our experimental data involving four uranium (233U 234U, 236U, and 238U) and five plutonium (239Pu, 24°Pu, 241Pu, 242Pu, and 244Pu) isotopes to determine ratios of fission cross sections relative to 235U. The data were gathered using ionization fission chambers and the time-of-flight technique at the LLL 100-MeV electron linear accelerator: measurements span the neutron energy range of 0.001 to 30 MeV. Experimental uncertainties common to past measurements were either eliminated or significantly reduced in this study by use of the threshold method, thereby making higher accuracies possible. The cross section ratios are absolute in the sense that they do not depend on the work of others. Results from our ratios involving 233U, 235U, 238U, and 239Pu are used to illustrate this method.