Understanding the RBS/c spectra of irradiated tungsten: A computational study

Understanding and identifying the defect structure of irradiated materials is of utmost importance to understand the properties of the material. Many experimental techniques exist to detect defects, one of them is Rutherford Backscattering Spectroscopy in channeling mode. This method can reveal the disorder created by defects as a function of depth. However, in order to understand the underlying defect structure resulting in the measured disorder, we need to understand how different defect morphologies affect the experimental signal. In this article we computationally investigate how all commonly found irradiation-induced defect structures in tungsten affect the signal. We found that open volume defects, vacancies and voids, show practically no yield, whereas the interstitials and dislocation loops show significant yields. We was also found that dislocation loop orientation with respect to the RBS/c channeling direction affected the results significantly, where some loops became almost invisible.