Investigation of isomer ratios in the reactions (γ, n) and (n, 2n) on nuclei ⁷⁶Ge and ⁸²Se

Authors

Satimbay Palvanov, National University of UzbekistanFollow
Turgunali Akhmadzhanov, National University of UzbekistanFollow

Abstract

The method of the induced activity measured the isomeric yield ratios and cross-sections ratios of reactions (γ, n) and (n, 2n) on nuclei ⁷⁶Ge and ⁸²Se. Samples of natural have been irradiated in the bremsstrahlung beam of the betatron SB-50 of National University of Uzbekistan in the energy range of 10-35 MeV with energy step of 1 MeV. For 14 MeV neutron irradiation, we used the NG-150 neutron generator of Institute of Nuclear Physics. The gamma spectra reactions products were measured with a spectroscopic system consisting of HPGe detector CANBERRA with energy resolution of 1.8 keV at 1332 keV gamma ray of ⁶⁰Co, amplifier 2022 and multichannel analyzer 8192 connected to computer for data processing. The filling of the isomeric and ground levels was identified according to their γ lines. Values η = Y_m/(Y_m + Y_g) at E_{γ max} = 30 MeV for the reaction (γ, n) on nuclei ⁷⁶Ge and ⁸²Se are respectively: 0.55±0.02 and 0.36±0.01 (Y_m/Y_g = 0.56±0.02). In the range 26-35 MeV the isomeric yield ratios η of the reaction (γ, n) on ₇₆Ge and ₈₂Se are obtained at first. The isomeric cross-section ratios σ_m/σ_g was determined in the case of the reaction (n, 2n). In order to obtain the absolute values of the cross sections for the ground state and for the isomeric state, use was made of methods based comparing the yields of the reaction under study and the monitoring reaction. The reaction ²⁷Al(n, α) ²⁴Na (T_1/2 = 15 h, E_γ = 1368 keV), whose cross section γm was 121.57±0.57 mb at E_n= 14.1 MeV, was taken for a monitoring reaction.

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Recommended Citation

Palvanov, Satimbay and Akhmadzhanov, Turgunali (2019) "Investigation of isomer ratios in the reactions (γ, n) and (n, 2n) on nuclei ⁷⁶Ge and ⁸²Se," Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences: Vol. 2: Iss. 4, Article 3.
DOI: https://doi.org/10.56017/2181-1318.1043