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

Full text (en)

Yu. N. Pavlenko¹, V. L. Shablov², V. O. Kyva¹, O. K. Gorpinich¹, N. L. Doroshko¹, A. V. Stepanyuk¹, O. I. Rundel¹, L. L. Dulger³, D. V. Kasperovych<sup>3

1</sup>Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
²Obninsk Institute for Nuclear Power Engineering, Obninsk, Russia
³Taras Shevchenko National University, Kyiv, Ukraine

Abstract: The processes of excitation and decay of high excited ⁵He resonances into the d + t channel have been studied in the reaction ⁷Li(d, α)⁵He* at the energy of deuteron beam E_d = 37 MeV. In the inclusive spectra of α-particles in addition to the contributions of well known ⁵He resonances, the high excited states with excitation energies E_x ∼ 19 and E_x > 20 MeV were observed. Cluster decay of these resonances was also identified in αd- and αt-coincidence spectra. For the first time, the decay into the d + t channel was observed for ⁵He resonances with E_x = 22 and 26 MeV. The determined resonance energy and width are partly agreed with the R-matrix analysis of data obtained at the study of d + ³H and n + ⁴He binary reactions. The possible Coulomb effects in three-particle channels of reaction ⁷Li(d, α)⁵He* are also analyzed for different conditions of observation of high excited ⁵He resonances.

Keywords: three-particle nuclear reaction, kinematically complete experiment, coincidence spectra, high excited resonances, decay channels, Coulomb interaction, resonance parameters.

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