QUANTUM-MECHANICAL SCATTERING OF AN ATOM FROM A RIGID HEMISPHERE ON AFLAT SURFACE

The scattering of a monoenergetic beam of atoms by a hard hemisphere o n a hard flat surface is formulated quantum mechanically. Differential and integral cross sections are calculated as a function of incident beam energy and incident angle and compared with the familiar results of scattering from a free hard sphere. Two types of interference proce sses are identified. In addition to the previously discussed off-specu lar reflection symmetry interferences, Rayleigh oscillations are found in the integral cross sections. They result from the interference of specular scattering from the hemisphere and from the flat surface. The ir phases are found to be independent of the angle of incidence when p lotted versus the normal component of the incident wave vector. (C) 19 97 American Institute of Physics.