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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A. A. Alzubadi^*, A. H. Hamade

Department of Physics, College of Science, University of Baghdad, Baghdad, Iraq

^*Corresponding author. E-mail address: ali.abdullatif@sc.uobaghdad.edu.iq

Abstract: The radiative proton capture reactions ¹²C(p, γ)¹³N, ¹⁴N(p, γ)¹⁵O, and ¹⁷O(p, γ)¹⁸F have been investigated within the framework of a direct capture model employing Woods - Saxon potentials. These reactions play a fundamental role in hydrogen burning through the carbon-nitrogen-oxygen (CNO) cycles in stellar interiors. Nuclear structure inputs constrained by experimental data have been used to calculate astrophysical S factors and scattering phase shifts. The calculated results show good agreement with available measurements, accurately reproducing both non-resonant contributions and narrow resonance features in the ¹²C(p, γ)¹³N and ¹⁷O(p, γ)¹⁸F reactions. The rate-limiting behavior of the ¹⁴N(p, γ)¹⁵O reaction in the CNO-I cycle has also been described with satisfactory precision. The findings provide improved inputs for stellar nucleosynthesis modeling and contribute to the understanding of low-energy nuclear capture processes relevant to astrophysics.

Keywords: radiative proton capture, CNO nuclear cycle, astrophysical S factor, direct capture model, stellar nucleosynthesis.

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