Backward rise in the 16O-12C inelastic scattering and the deformation of the repulsive core potential

Strong absorption is a common observation in the case of heavy ion collision. The strong absorption characteristic arises because of the opening up of large number of reaction channels. For certain light heavy ions such as 12C and 16O however, weaker absorption has been observed which manifests itself in the form of the presence of fairly high lying molecular resonances as well as nuclear rainbows. For systems in this category with non identical colliding partners there has been observation of significant rise of the elastic cross section at angles larger than 90 deg which is often accompanied by oscillatory structure. This is usually understood in terms of exchange of projectile target identity by the exchange of the residual entity made up of the differences of their masses and charges, which can be simulated by a repulsive core potential also. In the inelastic scattering of similar light heavy systems also a similar rise at the backward angles has been observed