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We study the fusion reaction of light systems with one dimensional barrier penetration model using the α − α double folding cluster (DFC) potential. We especially analyze the fusion cross sections of the 12 C+ 12 C, 16 O, 24 Mg, 28 Si, 16 O + 16 O, 24 Mg + 24 Mg, 28 Si, and 28 Si + 28 Si reactions. The results are compared with the one obtained with M3Y double folding (DFM) and the Akyüz-Winther (A-W) potentials. It is found that the calculations with DFM and DFC potentials can reproduced the experimental data much better than the calculations using the A-W potential. We also carried out an analysis on the astrophysical aspect of the 12 C + 12 C, 16 O, and 16 O + 16 O reactions. The calculations using DFC and DFM potentials could fit the S-factor data reasonably well. However, the calculated reaction rates are lower than the compilation of Caughlan and Fowler at low temperatures. In the important range of temperatures in stellar evolution, the DFC potential reproduce very satisfactory fitting to the experimental cross section and the S-factor data and gives a consistent prediction of astrophysical reaction rates. This finding indicates that the DFC potential could be used as an alternative potential to study the fusion reactions in the astrophysical interest.

Nuclear astrophysics is an interdisciplinary research field of nuclear physics and astrophysics, seeking for the answer to a question, how to understand the evolution of the universe with the nuclear processes which we learn. We review the research activities of nuclear astrophysics in east and southeast Asia which includes astronomy, experimental and theoretical nuclear physics, and astrophysics. Several hot topics such as the Li problems, critical nuclear reactions and properties in stars, properties of dense matter, r-process nucleosynthesis, and ν-process nucleosynthesis are chosen and discussed in further details. Some future Asian facilities, together with physics perspectives, are introduced.

This ongoing work reports the heavy doping effect on the Aluminum Nitride ( AlN ) semiconductor (SC) material, illustrated via its energy-band structure (EBS). The research correlates the bandgap energy (BE) and depletion region (DR), which are then applied to the estimation of light-emitting diode (LED) luminescence spectrum (LS). The measurements are compared with different dopant concentrations (1 × 10 cm -1 10 cm ). Having the Gallium Arsenide (GaAs) properties as the 18 −3 × 21 −3

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The transmission coefficient through a Coulomb barrier in nuclear reaction is obtained by using the WKB approximation. Hence, we can determine the exact tunneling probability from this method. This probability can be applied in calculating the astrophysical thermonuclear reaction rates. One of the most important aspects in calculating the reaction rates is the value of the most effective energy, EQ for the reaction to occur. The Gamow peak produces a nonlinear equation that is solved iteratively to produce EQ.

Abstract. The relevant astrophysical reaction rates which are derived from the reaction cross sections are necessary input to the reaction network. In this work, we analyse several theoretical models of the nuclear potential which give better prediction of the cross sections for some selected reactions.