INVESTIGATION OF THE Th-232 NEUTRON CROSS-SECTIONS IN RESONANCE ENERGY RANGE

Authors & Affiliations

Grigoriev Yu.V.1, Kitaev V.Ya.1, Sinitsa V.V.1, Zhuravlev B.V.1, Borzakov S.B.2, Faikov-Stanchik H.2, Ilchev G.L.2, Panteleev Ts.Ts.2,Kim G.N.3
1Institute of Physics and Power Engeneering, Obninsk, Russia
2Joint Institute for Nuclear Research, Dubna, Russia
3Pohang Accelerator Laboratory, POSTECH, Korea

Abstract

The alternative path in the development atomic energy is the uranium-thorium circle. In connection with this, the measurements of the 232Th neutron capture and total cross-sections and its resonance self-shielding coefficients in resonance energy range are necessary because of theirs insufficient accuracy. In this work, the results of the investigations of the thorium-232 neutron cross-sections are presented. The measurements have been carried out the gamma-ray multisection liquid detector and neutron detector as a battery of boron counters on the 120 m flight path of the pulsed fast reactor IBR-30. As the filter samples were used the metallic disks of various thickness and diameter of 45 mm. Two plates from metallic thorium with thickness of 0,2 mm and with the square of 4,5x4,5 cm2 were used as the radiator samples. The group neutron total and capture cross-sections within the accuracy of 2-7% in the energy range of (10 eV - 10 keV) were obtained from the transmissions and the sum spectra of gamma-rays from the fourth multiplicity to the seventh one. The neutron capture group cross-sections of 238U were used as the standard ones for obtaining of thorium ones. Analogous values were calculated on the GRUCON code with the ENDF/B-6, JENDL-3 evaluated data libraries. Within the limits of experimental errors there is observed an agreement between the experiment and calculation, but in some groups the experimental values are larger than the calculated ones.

Keywords
total cross-sections, resonance self-shielding coefficients, 232Th, 238U, accuracy, group cross-sections, evaluated data libraries, ENDF/B-6, JENDL-3

Article Text (in English, PDF, Translated by IAEA)

References

UDC 539.17.013

Problems of Atomic Science and Technology. Series: Nuclear Constants, issue 2, 2000