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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N. P. Saeed Abdulla¹, A. Pavithran¹, M. K. Preethi Rajan², R. K. Biju<sup>1,3,*

1</sup> Department of Physics, Government Brennen College, Dharmadam, Thalassery, Kerala, India
² Department of Physics, Payyanur College, Kannur University, Payyanur, Kannur, Kerala, India
³ Department of Physics, Pazhassi Raja N. S. S. College, Mattanur, Kannur University, Kannur, Kerala, India

^*Corresponding author. E-mail address: bijurkn@gmail.com

Abstract: In this study, we investigated two-proton radioactivity using the two-potential approach with a cosh-type potential to calculate the half-lives. The depth parameter V₀ = 58.405 MeV and diffuseness a = 0.537 fm in the cosh-type nuclear potential show the lowest standard deviation between the calculated and experimental half-lives. We proposed a linear formula for the formation probability using the linear relationship between log₁₀S_2p and A^1/3_d for the angular momentum state l = 0, 2 and 4. The model achieved the lowest standard deviation (σ = 1.09) using this linear formula compared to previous models and empirical formulas. The proposed formula significantly improved the accuracy of half-life predictions by reducing the standard deviation from 1.73 to 1.09. The predicted half-lives exhibit a hindrance factor in the range of -1.62 to 2.42, which is the lowest compared to earlier theoretical predictions. These results indicate that the proposed linear formation probability formula is suitable for reproducing experimental half-lives. The linear formula for formation probability was generalized for different angular momentum states by conducting least squares fit. We extended the half-life and formation probability predictions to 48 nuclei, and the predicted half-lives are in good agreement with the previous five theoretical models and two empirical formula predictions.

Keywords: two-potential approach, formation probability.

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