Low energy scattering in an argon and methane system

The theory for an argon-methane scattering system and several calculations in both the close coupling and coupled states schemes are presented. The problem is reduced to the irreducible A, E, and T representations and calculations in all these symmetries are performed and combined. Methane is treated as a rigid rotor. Two interaction potentials are employed and both contain an angle dependent term. Compound state resonances in this system are studied extensively and characterized. Close coupling and coupled states cross sections are compared in calculations with both interaction potentials and in the A and E representations. Coupled states cross sections in all three representations are presented over a range of energies from 25 to 90 MeV