A full relativistic treatment in analyzing α -12 C and α -40,42,44,48 Ca elastic scattering data at 1.37 GeV

A simple optical potential of Woods–Saxon form is used within the framework of the Klein–Gordon equation, for the first time, to analyze the elastic differential cross sections for 1.37 GeV (lab) incident α -particles on 12 C and calcium isotopes 40,42,44,48 Ca. The relativistic energy–momentum relation assures the need for relativistic calculations. As such, the previously determined parameters of all optical potential forms, used in the nonrelativistic Schr¨odinger equation and successfully analyzing the α - 12 C and α - 40,42,44,48 Ca data at 1.37 GeV, are to be revised. In the presence of Coulomb potential, as in the cases under consideration, the asymptotic solution of the Klein–Gordon equation differs from the corresponding one for the Schrödinger equation and the codes are modified accordingly.