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, Russian   Periodicity: 4 times per year   Open access peer reviewed journal

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A. Yu. Buki, I. S. Timchenko^*

National Science Center “Kharkiv Institute of Physics and Technology”, Kharkiv, Ukraine

^*Corresponding author. E-mail address: timchenko@kipt.kharkov.ua

Abstract: The experimental values of longitudinal response function of the ⁷Li nucleus have been obtained and these results have been used as the basis to find the Coulomb sum values at momentum transfers ranging from 0.55 to 1.625 fm^-1. The obtained experimental Coulomb sum values have been used to determine the total Coulomb energy of the ⁷Li nucleus. The result of the comparison of the Coulomb energy for the ⁷Li nucleus with the Coulomb energies for the ⁶Li and ⁴He nuclei a) is consistent with the paradox (revealed in the elastic electron scattering experiment) that the ⁷Li rms charge radius is smaller than the one of the ⁶Li nucleus; b) leads to the conclusion that, within the framework of the two-cluster model of the ⁷Li nucleus (α + t), the size of the α-cluster should be larger than the one of the ⁴He nucleus.

Keywords: ⁷Li, longitudinal response function, Coulomb sum, Coulomb energy, clusters.

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