Recently, we have developed a compact micro-PIXE system
using a tapered glass capillary for beam focusing. The purpose of
this study is to evaluate the performance of the micro-PIXE system
and reveal limiting factors with the help of numerical simulations.
In this paper, we first evaluate an effective radius of a micro beam
focused by a £10-lm capillary by using an edge-scanning method
and demonstrate a two-dimensional element mapping of copper
fine mesh. One of the important parameters to evaluate the beam
focusing ability is the beam-focusing factor, which is defined as the
ratio of beam current density at the capillary outlet to that at the
capillary inlet. If we assume that the focusing effect is attributed