Validity of Hill-Wheelar and WKB transmission coefficients at astrophysical energies

The study of fusion cross-section at deep sub-barrier energy regions for reactions involving light nuclei is of substantial importance in probing various astrophysical phenomena. In particular, the ¹²C+¹²C, ¹²C+¹⁶O and ¹⁶O+¹⁶O reactions play a central role in the later evolution stages of massive stars. In the present analysis, the nuclear potential is calculated using the double folding model embellished with the nuclear densities and R3Y effective nucleon nucleon interaction potential obtained within the relativistic mean-field formalism