Cross sections and resonance integrals for capture and fission in long-lived americium isotopes

Bak, M. A.; Krivokhatskii, A.S.; Petrzhak, K.A.; Petrov, Yu. G.; Romanov, Yu. F.; Shlyamin, E.A.

doi:10.1007/bf01120465

Cited by 19 publications

(9 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…3) However, there are discrepancies among reported data for the thermal-neutron capture cross section ( 0,g ) and the resonance integral (I 0,g ) of the 241 Am(n, ) 242g Am reaction. Measured data [4][5][6][7][8][9][10][11][12][13][14] are listed in Table 1. Conflicting data have been reported by many measurements for the neutron capture cross section of 241 Am.…”

Section: Introductionmentioning

confidence: 99%

Thermal-Neutron Capture Cross Section and Resonance Integral of Americium-241

Nakamura

Ohta

Harada

et al. 2007

J. Nucl. Sci. Technol.

View full text Add to dashboard Cite

The thermal-neutron capture cross section (0;g) and the resonance integral (I 0;g) leading to the ground state of 242 Am were measured by an activation method for neutron capture by 241 Am. A method with gadolinium, which was similar to the cadmium difference method, was used to measure the cross section 0;g with attention to resonances of 241 Am. Americium chloride samples containing 241 Am radioisotope were irradiated for 68 h in the long-irradiation plug of the Kyoto University Research Reactor, KUR. Wires of Co/Al and Au/Al alloys were used as monitors to determine thermal-neutron fluxes and epithermal Westcott's indexes at the irradiation positions. An-ray spectrometer was used to measure the activity ratios of 242 Cm to 241 Am. On the basis of Westcott's convention, the 0;g and I 0;g values were determined as 628 AE 22 b and 3:5 AE 0:3 kb, respectively.

show abstract

Section: Introductionmentioning

confidence: 99%

Thermal-Neutron Capture Cross Section and Resonance Integral of Americium-241

Nakamura

Ohta

Harada

et al. 2007

J. Nucl. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…As for the irradiation sample, a standardized 243 Am solution was used. The radionuclidic purity is 99.49% for 243 Am -1810AE70 a) Schuman and Berreth (1969) 19) -2160AE120 Folger et al (1968) 20) 78 2250 b) Bak et al (1967) 21) 73AE6 2300AE200 Ice (1966) 22) 84, 66 -Butler et al (1957) 23) 73:6AE1:8 2290AE50 a) Cut-off energy was taken as 0.625 eV. b) Cut-off energy was taken as 0.83 eV.…”

Section: Measurementsmentioning

confidence: 99%

Measurement of Effective Capture Cross Section of Americium-243 for Thermal Neutrons

Ohta

Nakamura

Harada

et al. 2006

J. Nucl. Sci. Technol.

View full text Add to dashboard Cite

The effective capture cross section of 243 Am for thermal neutrons was measured with an activation method. A sample of 243 Am was irradiated for 10 hrs at Kyoto University Reactor, KUR. After the irradiation, the sample was cooled for one month. In the cooling time, 244m Am and 244g Am produced by the irradiation decayed out to 244 Cm. The rays emitted from 243 Am and 244 Cm were measured with a silicon surface barrier detector. The neutron flux at the irradiation position was monitored using Au/Al and Co/Al wires. The effective capture cross section was deduced as 174:5AE5:3b from the-ray counts and the neutron flux. The quantity r ffiffiffiffiffiffiffiffiffiffi T=T 0 p in Westcott's convention was 0:037AE0:004. The present result was compared with the effective capture cross sections from the JENDL-3.3 and the Mughabghab evaluations.

show abstract

“…The differences in data are reflected in the resonance parameters found in evaluated libraries. The evaluation present in JEFF-3.2 adopts essentially the results provided by Lampoudis Gavrilov (1976) [64] 1800(90) 1570(10) b Harbour (1973) [65] 1538(118) 1330(117) b Hellstrand (1970) [66] 2700 c Bak (1967) [67] 2400 (200) 2100(200) b Nakamura 3500 (2007) [68] (300) b Maidana (2001) [69] 1665(91) b Deal (1964) [70] 900 Additional information concerning the capture cross section in the few-eV neutron energy range can be obtained from direct measurements of the resonance integral I 0 , I 0 = ∞ E c σ γ (E)/EdE, with E c usually being taken as 0.5 eV. In the case of the 241 Am(n,γ ) cross section the contribution of the first three resonances to I 0 is ∼75%, whereas the value of the integral above 20 eV represents less than 10%, according to parameters from JEFF-3.2.…”

Section: Comparison With Previous Measurements and Evaluationsmentioning

confidence: 99%

“…The total resonance integral is given by I 0 = I m 0 + I g 0 . Depending on the experimental technique, the integral experiments provide either all three resonance integrals [63][64][65]67], the total resonance integral [66], or the resonance integral feeding the ground state [68][69][70].…”

Section: Comparison With Previous Measurements and Evaluationsmentioning

confidence: 99%

Measurement and analysis of theAm241neutron capture cross section at the n_TOF facility at CERN

Mendoza¹,

Cano‐Ott²,

Altstadt³

et al. 2018

Phys. Rev. C

View full text Add to dashboard Cite

The 241 Am(n,γ ) cross section has been measured at the n_TOF facility at CERN with the n_TOF BaF 2 Total Absorption Calorimeter in the energy range between 0.2 eV and 10 keV. Our results are analyzed as resolved resonances up to 700 eV, allowing a more detailed description of the cross section than in the current evaluations, which contain resolved resonances only up to 150-160 eV. The cross section in the unresolved resonance region is perfectly consistent with the predictions based on the average resonance parameters deduced from the resolved resonances, thus obtaining a consistent description of the cross section in the full neutron energy range under study. Below 20 eV, our results are in reasonable agreement with JEFF-3.2 as well as with the most recent direct measurements of the resonance integral, and differ up to 20-30% with other experimental data. Between 20 eV and 1 keV, the disagreement with other experimental data and evaluations gradually decreases, in general, with the neutron energy. Above 1 keV, we find compatible results with previously existing values.

show abstract

Cross sections and resonance integrals for capture and fission in long-lived americium isotopes

Cited by 19 publications

References 7 publications

Thermal-Neutron Capture Cross Section and Resonance Integral of Americium-241

Thermal-Neutron Capture Cross Section and Resonance Integral of Americium-241

Measurement of Effective Capture Cross Section of Americium-243 for Thermal Neutrons

Measurement and analysis of theAm241neutron capture cross section at the n_TOF facility at CERN

Contact Info

Product

Resources

About