SOLITARY WAVES WITH DAMPED OSCILLATORY TAILS - AN ANALYSIS OF THE 5TH-ORDER KORTEWEG-DEVRIES EQUATION

We construct oscillatory solitary wave solutions of a fifth-order Kort eweg-de Vries equation, where the oscillations decay at infinity. Thes e waves arise as a bifurcation from the linear dispersion curve at tha t wavenumber where the linear phase speed and group velocity coincide. Our approach is a wave-packet analysis about this wavenumber which le ads in the first instance to a higher-order nonlinear Schrodinger equa tion, from which we then obtain the steady solitary wave solution. We then describe a complementary normal-form analysis which leads to the same result. In addition we derive the nonlinear Schrodinger equation for all wavenumbers, and list all the various anomalous cases.