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The main purpose of this work is to determine values of the asymptotic normalization coefficients for the virtual decays 6He+p → 7 Li(g.s.) and 6He+p → 7 Li(0.48 MeV). For this purpose, the recently measured experimental differential cross-section of the proton transfer reaction d(6He,7Li)n has been analyzed. The modified distorted wave born approximation is used to determine the values of the asymptotic normalization coefficients. The peripheral character of this reaction has been tested. It has been shown that this reaction is peripheral. New values of the asymptotic normalization coefficients for the virtual decays 6He+p → 7 Li(g.s.) and 6He+p → 7 Li(0.48 MeV) with their uncertainties have been obtained. [ABSTRACT FROM AUTHOR]

The method of impulse approximation is used to check the validity of the first-order optical potential for the elastic scattering problem of the neutron on the bound system, namely, C 1 2 (n. n) C 1 2 , Ca 4 0 (n , n) Ca 4 0 and Pb 2 0 8 (n , n) Pb 2 0 8 at incident neutron energies of 155 and 225 MeV. The optical potential is derived as the first-order term within the spectator expansion of a nonrelativistic multiple scattering terms using the Lippmann–Schwinger equation. The Modern realistic two-body potential ArgonneV18 in the momentum space was used as input in the Lippmann–Schwinger equation. The obtained results for the elastic differential cross-sections are in a good agreement with the experimental data taken from EXFOR Database for all studied targets at neutron energy above 200 MeV. As the neutron energy decreases down to approximately 155 MeV, the discrepancies with experimental data appear, which is in accordance with the impulse approximation formalism. [ABSTRACT FROM AUTHOR]

The total elastic nucleon-nucleus cross-section is calculated at energies up to 600 MeV for the elements C, Pb, O, 9Be, 4He, 2H, U and Al using a finite electromagnetic potential, which is obtained considering a Randall-Sundrum II scenario modified by the inclusion of compact extra dimensions. The length scale bound is set in the potential to compare with known experimental data. [ABSTRACT FROM AUTHOR]

The importance of nuclear reactions in low-density astrophysical plasmas with ion temperatures T ≥1010 K has been recognized for more than thirty years. However, the lack of comprehensive data banks of relevant nuclear reactions and the limited computational power have not previously allowed detailed theoretical studies. Recent developments in these areas make it timely to conduct comprehensive studies on the nuclear properties of very hot plasmas formed around compact relativistic objects such as black holes and neutron stars. Such studies are of great interest in the context of scientific programs of future low-energy cosmic γ-ray spectrometry. In this work, using the publicly available code TALYS, we have built a large nuclear network relevant for temperatures exceeding 1010 K. We have studied the evolution of the chemical composition and accompanying prompt gamma-ray emission of such high-temperature plasmas. We present the results on the abundances of light elements D, T, 3He, 4He, 6Li, 7Li, 9Be, 10B, 11B, and briefly discuss their implications on the astrophysical abundances of these elements. [ABSTRACT FROM AUTHOR]

In the present work we describe our results concerning the calculation of equation of state of symmetric zero temperature nuclear matter and the microscopic optical potential using the soft-core Argonne inter-nucleon potentials in first order Brueckner-Hartree-Fock (BHF) theory. The nuclear matter saturates at a density 0.228 nucleon/fm3 with 17.52 MeV binding energy per nucleon for Argonne av-14 and at 0.228 nucleon/fm3 with 17.01 MeV binding energy per nucleon for Argonne av-18. As a test case we present an analysis of 65 and 200 MeV protons scattering from 208Pb. The Argonne av-14 has been used for the first time to calculate nucleon optical potential in BHF and analyze the nucleon scattering data. We also compare our reaction matrix results with those using the old hard-core Hamada-Johnston and the soft-core Urbana uv-14 and Argonne av-18 inter-nucleon potentials. Our results indicate that the microscopic potential obtained using av-14 gives marginally better agreement with the experimental data than the other three Hamiltonians used in the present work. [ABSTRACT FROM AUTHOR]

In the present work, we report a microscopic optical potential analysis of the extensive neutron elastic scattering data from 12C, 40Ca and 208Pb in the 65-225 MeV energy region. Brueckner-Hartree-Fock method has been used to calculate the optical potential, where one requires internucleon potential to calculate reaction matrices which are then folded over the nucleon densities in the target nuclei. We report the predictions of the calculated potential using Argonne v-18 and Urbana v-14 local nucleon-nucleon potentials. The modern potential v-18 has been used for the first time to calculate the nucleon-nucleus optical potential. We also compare our predictions with the empirical potentials. The results indicate that the predictions of our microscopic potential are in better agreement with the experimental data as compared with the empirical global optical potentials. [ABSTRACT FROM AUTHOR]

Microscopic local optical potentials from two sources were calculated by folding the numerical g-matrices over point proton and neutron RMF densities of target nuclei. The hard-core Hamada–Johnston and the soft-core Urbana v-14 local inter-nucleon potentials have been used to generate numerical g-matrices by solving Bethe–Goldstone integral equation. The calculated potentials have been used to analyze successfully both the proton and neutron differential elastic scattering and polarization data at 65 MeV over a wide mass region of targets: 12C–208Pb. Comparison of the present results with a phenomenological optical model analyzes is also presented. Mass number dependence of the mean square radii of the two microscopic potentials are in close agreement with each other as well as with empirical results. [ABSTRACT FROM AUTHOR]