REX: A Computer Program for PIXE Spectrum Resolution of Aerosols

REX is a Fortran program for analysis of spectra obtained in PIXE analysis. The underlying model is still under development; however, one year of experience has demonstrated REX’s capability to be a fast reliable tool. The modeling of the different components and effects of the physical model is briefly discussed. Evidence is shown that secondary effects mostly due to Compton-scattering in and around the detector are important factors. In order to assure that heavy elements are recorded with sufficient sensitivity during short bombardment times, low energy X-rays are suppressed but not completely absorbed by use of a Mylar absorber with a hole. Such an absorber sometimes introduces severe problems for other techniques of spectrum analysis. However, to REX there is only the job to find the transmission curve of the absorber. (Less)