Asymptotic behavior of solutions of the linearized Euler equations near a shear layer

In this article, thanks to a new and detailed study of the Green’s function of Rayleigh equation near the extrema of the velocity of a shear layer, we obtain optimal bounds on the asymptotic behaviour of solutions to the linearized incompressible Euler equations both in the whole plane, the half plane and the periodic case, and improve the description of the so called “vorticity depletion property” discovered by F. Bouchet and H. Morita by putting into light a localization property of the solutions of Rayleigh equation near an extremal velocity.