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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K. A. Shaulskyi^*, S. P. Maydanyuk

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

^*Corresponding author. E-mail address: shaulskyi_kostiantyn@outlook.com

Abstract: Quantum effects in pycnonuclear reactions in compact stars at zero temperatures are studied with high precision. The reaction ¹⁶O + ¹⁶O was analyzed using the method of multiple internal reflections. The study of such reactions requires full consideration of quantum fluxes in the internal nuclear region. This reduces the rate and number of pycnonuclear reactions up to 1.8 times. This leads to the appearance of new states (which we call quasibound states) where the compound nuclear system is formed with maximal probability. As shown, the minimal energy of such a state is slightly higher than the energy of zero-mode oscillations in the lattice nodes in the pycnonuclear reaction, however, the probability of the formation of a compound system in a quasibound state is significantly greater than the corresponding probability in a state of zero-mode oscillations. It is reasonable to say that the frequency of reactions in quasi-bound states is more likely than in states of zero-mode oscillations. This can lead to significant changes in estimates of reaction rates in stars.

Keywords: pycnonuclear reactions, compact star, neutron star, multiple internal reflections, coefficients of penetrability and reflection, fusion, quasibound state, compound nucleus, dense nuclear matter, zero mode oscillations, tunneling.

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