Comparative study of measured and critically evaluated resonance integral to thermal cross section ratios, III

1989 ◽  
Vol 133 (1) ◽  
pp. 131-151 ◽  
Author(s):  
F. De Corte ◽  
A. Simonits ◽  
A. De Wispelaere
Keyword(s):  
Comparative Study ◽  
Cross Section ◽  
Resonance Integral ◽  
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).

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.

Anomalous 96Zr resonance integral to thermal activation cross-section ratio and the neutron activation resonance integral of 94Zr and 96Zr

1970 ◽  
Vol 48 (20) ◽  
pp. 2362-2370 ◽  
Author(s):  
M. D. Ricabarra ◽  
R. Turjanski ◽  
G. H. Ricabarra
Keyword(s):  
Cross Section ◽  
Mass Region ◽  
Resonance Integral ◽  
Activation Cross Section ◽  
Energy Agency ◽  
Order Of Magnitude ◽  
Gamma Sources ◽  
Strength Functions ◽  
Thermal Cross Section ◽  
Reduced Activity

Values of the reduced activity resonance integral relative to the thermal cross section, I′/σ0, of 96Zr and 94Zr were determined relative to gold by measuring cadmium ratios in a reactor spectrum.Due to the anomalous characteristics of 96Zr a measurement of I′/σ0 for 96Zr was undertaken in a "quasi" thermal spectrum.96Zr and 94Zr activation resonance integrals were also determined by measuring the ratio of effective activation cross section of zirconium to 55Mn. International Atomic Energy Agency (IAEA) calibrated gamma sources were used to determine the samples' absolute activities. A lithium-drifted germanium γ-ray spectrometer was used in all cases to resolve the activities of the irradiated samples.The results for 96Zr are I′/σ0 = 879 ± 96, I′ = 4.97 ± 0.50 b, and σ0 = 5.7 ± 10 mb; for 94Zr I′/σ0 = 5.87 ± 0.05, I′ = 0.369 ± 0.037 b, and derived σ0 = 63 ± 8 mb.I′/σ0 for 96Zr is an order of magnitude or more greater than that found for stable isotopes. This suggests that almost 100% of the activation resonance integral of 96Zr consists of p-neutron captures. This fact is not consistent with the present knowledge of p-strength functions in the 90 < A < 130 mass region.

MEASUREMENT OF RADIATIVE CAPTURE RESONANCE INTEGRALS IN A THERMAL REACTOR SPECTRUM, AND THE THERMAL CROSS SECTION OF Pu-240

1960 ◽  
Vol 38 (1) ◽  
pp. 57-77 ◽  
Author(s):  
W. H. Walker ◽  
C. H. Westcott ◽  
T. K. Alexander
Keyword(s):  
Cross Section ◽  
Neutron Beam ◽  
Cross Sections ◽  
Radiative Capture ◽  
Effective Cross Section ◽  
Mean Value ◽  
Resonance Integral ◽  
Thermal Reactor ◽  
Thermal Cross Section ◽  
Radiative Neutron Capture

An apparatus is described which detects γ-rays emitted by a thin target placed in a well-denned neutron beam. It has been used to determine the Cd ratios of Au and Pu-240, from which the ratio of the resonance integral to the 2200 m/s cross section for radiative neutron capture in Pu-240 has been deduced, using Au as a reference standard. Using this ratio and previously measured values of the resonance integral of Pu-240 and its effective cross section in two positions in the NRX reactor, three separate estimates of the 2200 m/s cross section of Pu-240 have been made. The mean value is 270 ± 17 barns.In an auxiliary experiment to indicate the shape of the epithermal spectrum of the neutron beam, the activation Cd ratios of Mn and In were compared with that of Au. These results, combined with the known 2200 m/s capture cross sections of these nuclides, yield new values of the radiative capture resonance integrals for both Mn and In.

scholarly journals Thermal Cross Section And Resonance Integral Measurements Of57Co(n,γ)58Co Reaction

2002 ◽  
Vol 39 (sup2) ◽  
pp. 441-443 ◽  
Author(s):  
Nora Lía Maidana ◽  
Vito Roberto Vanin ◽  
Paulo Regmaldo Pascholati ◽  
Mauro da Silva Dias ◽  
Marina Fallone Koskinas
Keyword(s):  
Cross Section ◽  
Resonance Integral ◽  
Thermal Cross Section

THE CROSS SECTION FOR THE REACTION Cs135(n, γ)Cs136

1958 ◽  
Vol 36 (7) ◽  
pp. 863-870 ◽  
Author(s):  
A. P. Baerg ◽  
F. Brown ◽  
M. Lounsbury
Keyword(s):  
Cross Section ◽  
Reaction Rate ◽  
Effective Cross Section ◽  
Reaction Rates ◽  
Resonance Integral ◽  
A Value ◽  
The Cross ◽  
Thermal Cross Section

The effective cross section for the reaction Cs135 (n, γ) Cs136 with reactor neutrons is 10.4 ± 0.5 barns. The measured reaction rate under cadmium yields a value of 61.7 ± 2.3 barns for the resonance integral of Cs135. The thermal cross section is 8.7 ± 0.5 barns as obtained by combining the reaction rates for uncovered and cadmium-covered samples.

Sign in / Sign up

Export Citation Format

Share Document