Theoretical calculations for the reaction 241Am(n, 2n) in the framework of the Hauser-Feshbach model

The cross section of the reaction 2ilAm(n, 2n), has been measured by the activation method in the range from 9.6 to 11.4 MeV, at the Tandem accelerator facility of NCSR Demokritos. Statistical model calculations in the framework of the Hauser- Feshbach theory have been performed, and the first results are presented. Experimental data on the neutron induced fission cross section of 241Am, have been used as a constraint for the calculations. The results of the investigation are presented in comparison with experimental data and previous theoretical evaluations.

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High-resolution evaluation of the U5(n,f) cross section from 3 keV to 30 keV

EPJ Web of Conferences ◽

10.1051/epjconf/201921102003 ◽

2019 ◽

Vol 211 ◽

pp. 02003

Author(s):

I. Duran ◽

C. Paradela ◽

M. Caamaño ◽

P. Cabanelas ◽

L. Tassan-Got ◽

...

Keyword(s):

Experimental Data ◽

High Resolution ◽

Cross Section ◽

Resonance Region ◽

Fission Cross Section ◽

Energy Calibration ◽

Fine Grid ◽

Resonance Analysis ◽

Reference File ◽

Induced Fission

235U neutron-induced fission cross-section is commonly used as reference for determining other isotope fission cross-section. However, below 150 keV this cross section is only included as Standard at the thermal point and recently its integral value between 7.8 eV and 11 eV [1]. The resolved resonance region, spanning up to 2.25 keV, has been reevaluated with high resolution in the last ENDF/B-VIII release [2] and a SAMMY resonance analysis was done by L. Leal et al. [3] including the CERN-nTOF experimental work of Paradela el al. [4] up to 10 keV, taken into account the IAEA Reference file. In this work the 235U(n,f) low-background and high-resolution experimental data obtained at the CERN-nTOF facility is combined with previous high-resolution experimental data, in order to produce a very fine grid dataset with normalisation to the IAEA Reference file. The extremelyhigh energy calibration required to reproduce the resonance sharp profiles is based on the nTOF DAQ system with a resolution below 0.1% with reference to the 8.78 eV resonance and to the sharp Al(n,g) capture dip at 5.904 keV. The comparison of the so-evaluated profile with the experimental data and with the evaluated ones will be discussed.

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Study of the neutron-induced fission cross section of 237Np at CERN's n_TOF facility over a wide energy range

EPJ Web of Conferences ◽

10.1051/epjconf/202023905006 ◽

2020 ◽

Vol 239 ◽

pp. 05006

Author(s):

A. Stamatopoulos ◽

A. Tsinganis ◽

M. Diakaki ◽

N. Colonna ◽

M. Kokkoris ◽

...

Keyword(s):

Experimental Data ◽

Energy Range ◽

Cross Section ◽

Fuel Cycle ◽

Fission Cross Section ◽

Nuclear Model ◽

Wide Energy Range ◽

Model Parameters ◽

Wide Range ◽

Induced Fission

Neutron-induced fission cross sections of isotopes involved in the nuclear fuel cycle are vital for the design and safe operation of advanced nuclear systems. Such experimental data can also provide additional constraints for the adjustment of nuclear model parameters used in the evaluation process, resulting in the further development of fission models. In the present work, the 237Np(n,f) cross section was studied at the EAR2 vertical beam-line at CERN's n_TOF facility, over a wide range of neutron energies, from meV to MeV, using the time-of-flight technique and a set-up based on Micromegas detectors, in an attempt to provide accurate experimental data. Preliminary results in the 200 keV – 14 MeV neutron energy range as well as the experimental procedure, including a description of the facility and the data handling and analysis, will be presented.

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Neutron-induced fission cross-section measurement of 234U with monoenergetic beams in the keV and MeV range using MicroMegas detectors

HNPS Proceedings ◽

10.12681/hnps.1875 ◽

2019 ◽

Vol 24 ◽

pp. 250

Author(s):

A. Kanellakopoulos ◽

A. Stamatopoulos ◽

A. Tsinganis ◽

M. Kokkoris ◽

R. Vlastou ◽

...

Keyword(s):

Cross Section ◽

Neutron Beam ◽

Cross Sections ◽

Fission Cross Section ◽

Incident Neutron ◽

Tandem Accelerator ◽

Cross Section Measurement ◽

Preliminary Results ◽

Section Measurement ◽

Induced Fission

The fission cross-section of 234U was measured at incident neutron energies between 300 and 500 keV and 4 and 5 MeV with a setup based on “microbulk” MicroMegas detectors. The standard 235,238U fission cross-sections were used as reference. The neutron beams were produced via the 7Li(p,n) and the 2H(d,n) reactions at the neutron beam facility of the 5.5 MeV Tandem accelerator laboratory at NCSR “Demokritos”. The mass of the actinide content of the targets used and of their impurities was quantitatively determined via α – spectroscopy. The developed methodology and preliminary results are presented.

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