The authors have studied the Gamma ₈ Jahn-Teller system in linear and equal coupling and have used the invariance of the resulting model under the five-dimensional rotation group to reduce the problem to the solution of a pair of radial differential equations. They have computed the energy levels, the absorption spectrum at 0K, the emission spectrum at 0K and the Ham reduction factors in the ground state. They have examined low-lying energies in strong coupling and have identified Slonczewski resonances. The absorption spectrum was compared with that found for the ²P_1/2 to ²P_3/2 transition of Tl⁰ in alkali halides by Delbecq et al. (1967) and was found to agree qualitatively.