Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

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I. M. Vyshnevskyi, V. O. Zheltonozhskyi, A. M. Savrasov, E. P. Rovenskykh

Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine

Abstract: Isomeric yield ratios of ⁹⁰Rb, ¹³³Te, ¹³⁴I and ¹³⁵Xe fission fragments have been measured. Fragments have been created in photofission of ²³³U nuclei by bremmsstrahlung photons with end-point energy near 10.5 and 17 MeV and of ²⁴¹Am nuclei irradiated by bremmsstrahlung photons with end-point energy near 9.8 MeV. Experimental values of isomeric yield ratios have been calculated with allowing for the contribution from beta-decay of isobaric nuclei in yields of investigated isotopes. Average angular moments of investigated fission fragments have been determined using the statistical model of decay.

Keywords: photofission, isomeric yields ratios, activation method, TALYS calculations.

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