ABSTRACT
This chapter is concerned with the calculation of X-ray spectra emitted from target materials after bombardment with electrons. It considers only X-ray sources that are thick target X-ray tubes with reflection geometries. The complexity and sophistication required in modeling X-ray spectra depends on the task at hand. The chapter discusses the empirical and the so-called “semi-empirical” spectrum models, as well as the use of Monte Carlo simulations. An X-ray spectrum is commonly specified in terms of photon flux per unit energy, intensity per unit energy, or intensity per unit frequency. Discussion of X-ray emissions has so far focused on the continuous spectrum of bremsstrahlung. However, an important part of the spectrum can consist of characteristic X-rays emitted from the L- or K-shells of the target atoms. The characteristic portion of the spectrum is only treated adequately in all the semi-empirical models to the extent that a large error is acceptable.
