2 3 D ec 1 99 8 Wave channeling of X - rays in narrow rough capillaries - non Andronov - Leontovich theory

The effect of capture of X-ray beam into narrow submicron capillary was investigated with account for diffraction and decay of coherency by roughness scattering in transitional boundary layer. In contrast to well-known Andronov-Leontovich approach the losses do not vanish at zero gliding angle and scale proporpional to the first power of roughness amplitude for small gliding angles. It was shown that for small correlation radius of roughness the scattering decay of coherency can be made of the same order as absorption decay of lower channeling modes to produce angular collimation of X-ray beams. Estimates were given for optimum capillary length at different roughness amplitudes for angular sensitivity of X-ray transmission and chenneling effects that can be useful for designing of detector systems.