Study of the effects of Pauli blocking and Pauli non-locality on the   optical potential
  Elastic scattering angular distributions for systems with reduced mass between 3 and 34 and energies varying between 25 and 120 MeV/nucleon were analyzed. The stable $^4$He, its exotic partner $^6$He, and the weakly bound $^{6,7}$Li nuclei were included as projectiles in the systematics. Optical model data analyzes were performed with an adjustable factor of normalization included in the imaginary part of the potential. These analyzes indicated a reduction of absorption for systems with small reduced masses that was detected due to the refractive nature of the scattering by light systems. 
M. A. G. Alvarez, N. Alamanos, L. C. Chamon and M. S. Hussein