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arXiv · 1901.09705

Theoretical exploration of $S$-factors for nuclear reactions of astrophysical importance

Vinay Singh·Joydev Lahiri·D. N. Basu
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Abstract

We present here a robust analytical model based on nuclear reaction theory for non-resonant fusion cross sections near Coulomb barrier. The astrophysical $S$-factors involving stable and neutron rich isotopes of C, O, Ne, Mg and Si for fusion reactions have been calculated in the centre of mass energy range of 2-30 MeV. The model is based on the tunneling through barrier arising out of nuclear, Coulomb and centrifugal potentials. Our formalism predicts precisely the suppression of $S$-factor at sub-barrier energies which are of astrophysical interest. The cross sections can be convoluted with Maxwell-Boltzmann distribution of energies to obtain thermo- or pycno- nuclear reaction rates relevant to nucleosynthesis at high density environments and stellar burning at high temperatures as well as for $^{34}$Ne $+$ $^{34}$Ne fusion occurring in the inner crust of accreting neutron stars.

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Vinay Singh, Joydev Lahiri, D. N. Basu. 2019-01-28. Theoretical exploration of $S$-factors for nuclear reactions of astrophysical importance. https://doi.org/10.1016/j.nuclphysa.2019.05.005

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