ERYA-Bulk and ERYA-Profiling: An application for quantitative PIGE analysis

Compute the gamma-ray yield coming from a sample bombarded by a energetic (few MeV) beam of charged particles (namely protons). The yield corresponding to a given element depends on the mass fraction of this element and on the major composition of the sample which determines the rate of energy loss by the beam. It also depends on the detector efficiency, the collected beam charge (i.e., number of projectiles) and the cross-sections of the relevant gamma-producing nuclear reaction. All data inputs can be loaded from a file or inserted by the user. The energy straggling along the beam interaction with the sample, irrelevant for bulk analysis, is determinant for depth profiling. The yield calculation is made by numerical integration of an analytical formula that depends on several quantities which can be analytical in nature or approximated by interpolation (the cross-section data interpolation is one example). The straggling and energy dispersion also depends on energy distributions which have different numerical approximations. A modular approach using the object-oriented programming helps to implement different models to the main integration routine, and make the source code more readable and prone for future extensions. A fitting feature was implemented on ERYA-Bulk to adjust the sample composition to the experimental yield results.