Airy minima in 4He + 28Si elastic and inelastic scattering

We present the results of the S-matrix description of the He-4 + Si-28 elastic and inelastic scattering differential cross-sections between 40 and 240 MeV with allocation of Airy minima of various orders. The first-order Airy minima have been unambiguously identified in the differential cross-sections for elastic scattering and inelastic scattering to the first 2(+) state of Si-28 at energies E = 40-166 MeV, and the second-order Airy minima - at E = 40-58 MeV. The angular positions of these minima obey an inverse dependence on energy. The intensities of nuclear refraction and absorption also obey the same energy dependence.