Yazar "Dehghani, V." seçeneğine göre listele

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    Calculations on the proton decay with modified preformation probability
    (World Scientific Publ Co Pte Ltd, 2022) Soylu, A.; Koyuncu, F.; Alavi, S. A.; Dehghani, V.
    In this paper, the investigations have been conducted on the half-lives of proton radioactivity of 32 nuclei. The main goal of the paper is to improve the formation probability (S-p) that proposed by Chen et al. [Eur. Phys. J. A 57 (2021) 1]. The obtained results in mentioned paper have been reproduced with uncertainties for all parameters by fitting the experimental data of proton emitters. To carry out the further investigations, we have proposed a new S-p which has a different type of shape from linear. The replacement of the linear form with an exponential, one of the formation probabilities, has affected the rms result positively. The new form of S-p, which has been presented in this study, depends on the mass number of daughter nucleus like the previous one but in exponential form. The obtained findings here may be important for studies while making new predictions.
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    ?-decay half-lives of uranium isotopes using a two-potential approach
    (Amer Physical Soc, 2024) Alavi, S. A.; Dehghani, V.; Soylu, A.; Koyuncu, F.
    Using three methods, the two-potential approach (TPA), the direct method, and the distorted-wave method, the decay widths of uranium isotopes were calculated. Wider ranges of application of the TPA were checked and independence of the decay width to the separation point, from the prebarrier position to the postbarrier position, was observed. The equivalence of the direct and the distorted-wave methods for spherical nuclei was discussed Simplified versions of the TPA and the direct method were used and satisfactory results for the TPA version and the same results for two forms of the direct method were obtained. By presenting different experimental half-lives with remarkable uncertainties, especially for lighter isotopes, the calculated preformation probabilities using the TPA bound wave function and the TPA decay width were compared and reasonable agreement was observed for favored transitions.
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    Proton radioactivity half-lives with nuclear asymmetry factor
    (Iop Publishing Ltd, 2021) Soylu, A.; Koyuncu, F.; Gangopadhyay, G.; Dehghani, V.; Alavi, S. A.
    The dependence of proton emission half-lives on the nuclear asymmetry parameter is investigated using the WKB method and two types of empirical formula. Using the single-folding formalism with asymmetry-dependent nuclear radius and surface diffuseness of nuclear matter, the nuclear potential and consequently the half-life are functions of the asymmetry factor. Despite small values of asymmetry in neutron-deficient proton emitters, noticeable changes in the half-lives are observed. The addition of an asymmetry parameter term to the two forms of empirical formulas leads to a reduction in the rms error for ground state and isomeric transitions. A noticeable reduction of about 43% is obtained for isomeric transitions in the second form of the empirical formula. Considering ground state transitions in two categories, odd-even and odd-odd emitters, and adopting deformation and asymmetry-dependent empirical formulas, the rms decreases remarkably. The lowest values of rms errors, viz. 0.1492, 0.2312, and 0.1999, are obtained for the aforementioned empirical formulas for ground state transitions of odd-even and odd-odd emitters and for all isomeric transitions, respectively.