Closed-orbit distortions of periodic FODO lattices due to plane ground waves

An analytical investigation of the closed-orbit distortions due to ground waves has been made for a model periodic FODO lattice. The response of the closed orbit to a single wave and the rms response to an ensemble of uncorrelated waves are expressed as a function of C/λ (ring circumference /wavelength). It is found that transverse focusing (represented by the tune Q) and superperiodic lattice geometry (represented by the number of FODO cells N) can resonantly amplify the closed-orbit response to certain frequencies. As a consequence, as C/λ increases through some values mN±Q (m positive integer), the response function is expected to show a steplike behavior followed by a slow fall off. The results are compared with models that have both continuous focusing and uncorrelated quadrupole motion. Numerical examples are presented. (author) 5 refs., 5 figs