A CAPILLARY CONCENTRATOR FOR AN X-RAY MICROPROBE

Capillary concentrators are examined analytically and by computer simulations for applications in third-generation synchrotron-radiation bean-dines. A comparison is made between them and focusing mirrors for producing a small spot of X rays. Both devices are achromatic and useful for experiments that require an X-ray microprobe which delivers X rays over a broad band of energies. It is shown that the capillary concentrator produces an order of magnitude more intensity than the focusing mirror for spots below micrometer dimensions. The simulations also show that the exact profile of the capillary is not important except for the region near the outlet.