A versatile Monte Carlo package for computation of efficiencies of Si(Li), SDD and Ge detectors

摘要

Currently, most detector efficiency calculations for X-ray detectors assume that the source is a point source on the axis of symmetry of the detector, but this is not always accurate. We have devised a Monte Carlo program to simulate photon transport in Si(Li), SOD and planar Ge detectors that natively handles finite, tilted and off-axis sources. Although electron transport is not handled at this stage, photon transport is completely handled, including absorption from filters and multiple scattering in the detector crystal. The K escape peak is handled for both silicon and germanium detectors, and the L escape peak is also handled for germanium detectors. Our efficiency results compare very well with previous work when idealized systems are simulated, and the effect of a non-idealized system is presented. Escape peak intensity ratios are given for both silicon detectors (K peak only) and germanium detectors (K and L peaks), and the results for the K escape peaks agree well with previous work. Results are presented for a recent annular detector system, which is a good example of systems that are poorly handled under previous efficiency calculations.