Improved 242Pu(n,$ \gamma$) thermal cross section combining activation and prompt gamma analysis

2019 ◽  
Vol 55 (5) ◽  
Author(s):  
J. Lerendegui-Marco ◽  
C. Guerrero ◽  
T. Belgya ◽  
B. Maróti ◽  
K. Eberhardt ◽  
...  
Keyword(s):  
Cross Section ◽  
Prompt Gamma ◽  
Gamma Analysis ◽  
Thermal Cross Section

scholarly journals Improved accuracy in the determination of the thermal cross section of ${}^{14}{\rm N}({\rm n},{\rm p}){}^{14}{\rm C}$ for neutron lifetime measurement

2019 ◽  
Vol 2019 (9) ◽  
Author(s):  
R Kitahara ◽  
K Hirota ◽  
S Ieki ◽  
T Ino ◽  
Y Iwashita ◽  
...  
Keyword(s):  
Cross Section ◽  
Lifetime Measurement ◽  
Reaction Cross ◽  
Proton Accelerator ◽  
Incident Neutron ◽  
Neutron Lifetime ◽  
The Cross ◽  
Thermal Cross Section ◽  
Improved Accuracy

Abstract In a neutron lifetime measurement at the Japan Proton Accelerator Complex, the neutron lifetime is calculated from the neutron decay rate and the incident neutron flux. The flux is obtained by counting the protons emitted from the neutron absorption reaction of ${}^{3}{\rm He}$ gas, which is diluted in a mixture of working gas in a detector. Hence, it is crucial to determine the amount of ${}^{3}{\rm He}$ in the mixture. In order to improve the accuracy of the number density of the ${}^{3}{\rm He}$ nuclei, we have suggested using the ${}^{14}{\rm N}({\rm n},{\rm p}){}^{14}{\rm C}$ reaction as a reference because this reaction involves similar kinetic energy to the $^3$He(n,p)$^3$H reaction and a smaller reaction cross section to introduce reasonable large partial pressure. The uncertainty of the recommended value of the cross section, however, is not satisfied with our requirement. In this paper we report the most accurate experimental value of the cross section of the $^{14}$N(n,p)$^{14}$C reaction at a neutron velocity of 2200 m s$^{-1}$, measured relative to the $^3$He(n,p)$^3$H reaction. The result was 1.868 $\pm$ 0.003 (stat.) $\pm$ 0.006 (sys.) b. Additionally, the cross section of the $^{17}$O(n,$\alpha$)$^{14}$C reaction at the neutron velocity is also redetermined as 249 $\pm$ 6 mb.

Optical and thermal cross-section of interface states from photocapacitance measurements

1986 ◽  
Vol 29 (11) ◽  
pp. 1195-1203 ◽  
Author(s):  
J.R. Morante ◽  
A. Herms ◽  
J. Samitier ◽  
A. Cornet ◽  
E. Lora-Tamayo
Keyword(s):  
Cross Section ◽  
Interface States ◽  
Thermal Cross Section

THE RATIO OF THE RESONANCE INTEGRAL TO THE THERMAL NEUTRON CROSS SECTION FOR Sm152

1961 ◽  
Vol 39 (8) ◽  
pp. 1184-1192 ◽  
Author(s):  
W. H. Walker ◽  
R. E. Green
Keyword(s):  
Total Cross Section ◽  
Cross Section ◽  
Neutron Cross Section ◽  
Resonance Integral ◽  
Half Maximum ◽  
Thin Foils ◽  
Flight Measurement ◽  
Thermal Neutron Cross Section ◽  
Thermal Cross Section ◽  
Made In

Cadmium ratio measurements have been made in similar lattice positions in ZEEP with thin foils of Sm152 and gold. From a comparison of these cadmium ratios we find[Formula: see text]If gσ0 is assumed to be 212 ± 12 barns, then I′ = 3100 ± 200 barns. On the assumption that only one resonance in Sm152, at 8 ev, contributes appreciably to both the resonance integral and the thermal cross section, it follows that g = 1 and that Γ, the width at half-maximum of the total cross section resonance, is 193 ± 5 milli-ev. Because of the appreciable disagreement between this value and one reported earlier, a new time-of-flight measurement of the resonance parameters has been made, and it is reported in the next paper (Chrien 1961).

scholarly journals Measurement of the 13C(n,$\gamma$) thermal cross section via neutron irradiation and AMS

2019 ◽  
Vol 55 (11) ◽  
Author(s):  
T. Wright ◽  
S. Bennett ◽  
S. Heinitz ◽  
U. Köster ◽  
R. Mills ◽  
...  
Keyword(s):  
Activation Analysis ◽  
Cross Section ◽  
Research Reactor ◽  
Gamma Ray ◽  
Beam Line ◽  
Prompt Gamma ◽  
High Flux ◽  
Accelerator Mass Spectrometer ◽  
Thermal Cross Section ◽  
Good Agreement

Abstract.Ampoules of amorphous 99.5% enriched 13C were irradiated at the PF1b neutron beam line at the high-flux ILL research reactor in order to produce 14C atoms. The precise ratio of 14C/13C was subsequently measured at the VERA Accelerator Mass Spectrometer, allowing the 13C(n,$ \gamma$γ)14C thermal cross section to be accurately determined. This is the first measurement of this cross section at sub-eV energies via this technique and the result of $ 1.52 \pm 0.07$1.52±0.07 mb for the thermal cross section is in good agreement with other recent measurements which were performed via Prompt Gamma-ray Activation Analysis.

Measurement and Evaluation of the Activation Resonance Integral of 146Nd, 148Nd, and 150Nd

1973 ◽  
Vol 51 (13) ◽  
pp. 1454-1462 ◽  
Author(s):  
M. D. Ricabarra ◽  
R. Turjanski ◽  
G. H. Ricabarra
Keyword(s):  
Cross Section ◽  
Gamma Ray ◽  
Resonance Integral ◽  
Correction Factors ◽  
Gamma Ray Spectrometer ◽  
Spectral Correction ◽  
Reactor Spectrum ◽  
Measurement And Evaluation ◽  
Thermal Cross Section ◽  
Integral Data

Values of the ratio of the reduced activition resonance integral to the thermal cross section, I′/σ0, of 146Nd, 148Nd, and 150Nd were determined relative to gold by measuring cadmium ratios. A lithium-drifted germanium gamma-ray spectrometer was used to resolve the activities of the irradiated samples. The results are: for 146Nd I′/σ0 = 1.42 ± 0.10 and with an assumed σ0 = 1.4 b, I′ = 1.99 ± 0.20 b; for 148Nd I′/σ0 = 4.22 ± 0.14 and with an assumed σ0 = 2.5 b, I′ = 10.5 ± 0.9 b; and for 150Nd I′/σ0 = 13.7 ± 0.8 and with an assumed σ0 = 1.2 b, I′ = 16.4 ± 2.8 b.The resolved and unresolved epithermal integrals of 146Nd, 148Nd, and 150Nd were calculated. Values of the spectral correction factor were also calculated, so the resonance integral could be obtained from the epithermal integral data measured in our reactor spectrum in this experiment. Epithermal integral and spectral correction factors are listed in the text.The most important result of this investigation is that the 148Nd activation reduced resonance integral is about half of the previously recommended value and consequently the radiative width for 148Nd is also about half of the previously accepted value.

Thermal Cross Section and Resonance Integrals of Cadmium-114

1967 ◽  
Vol 28 (1) ◽  
pp. 158-158
Author(s):  
S. Pearlstein ◽  
R. F. Milligan
Keyword(s):  
Cross Section ◽  
Thermal Cross Section
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