USE OF THE ALPHA-PARAMETER METHOD TO CALCULATE MATRIX CORRECTIONS FORINFINITELY THICK TARGETS (TTPIXE) WITH 2 DIFFERENT INCIDENT BEAM ENERGIES

The alpha parameter correction method for calculating matrix effects i n PIXE data does not require a priori knowledge of the major element c omposition of the matrix but implies the determination of a so-called alpha parameter linking two independent phenomena: X-ray absorption an d proton energy loss. The method extrapolated to the infinitely thick targets (TTPIXE) has been previously studied using two PIXE measuremen ts in two different geometric configurations. The present Study deals with the possibility of using pairs of PIXE measurements at two differ ent energies to obtain the alpha corresponding to thick samples (TTPIX E). The experimental conditions and error minimization problems are di scussed. General tables allowing an easy use of the method are present ed.