Ray travel time and distance for the planar polytrope

Abstract

Ray travel time and distance are determined for the planar polytrope using analytic techniques that are specialized to plane stratified media. It is found that an adiabatically stratified polytrope yields non-dispersed wave fields for a full circuit of a ray through a trapping region. Non-adiabacity, however, leads to dispersion, and a consequent loss of correlation with successive circuits of the trapping region. An acoustic waveguide with fixed boundaries and a similar waveguide containing an isothermal stratified medium are also examined to illustrate the approach and to highlight various aspects of the ray behavior.