ANALYSIS OF NUCLEUS-NUCLEUS FUSION CROSS-SECTION AT EXTREME SUB-BARRIER ENERGIES

The nucleus nucleus potential is expressed phenomenologically by a new radial form as an alternative to the conventional Woods-Saxon form. By virtue of novel representation of the surface diffuseness, the potential added with the electrostatic part generates a unique barrier potential which provides simultaneous explanations of two important mechanisms namely elastic scattering and fusion in a heavy-ion reaction within the framework of optical potential model of scattering and region-wise absorption in analytical form. The drastic falloff of experimental results of fusion cross-section (sigma(fus)) at extreme sub-barrier energy (E) and its manifestation depicting maximum in S (= E sigma(fus)e(2 pi eta)) factor and steep rise in L (= dIn(E sigma(fus))/dE) factor are explained with remarkable success.