Haven't been able to find the answer anywhere IRL yet, so I thought I'd see if someone in the PhysicsForums could help me with this one. When doing SEM/EDS (EDX/EDXS) (~equivalent to x-ray fluorescence) analysis it looks as if my europium containing samples contain copper as well, which'd surprise me a lot. Actually, there seems to be a correlation in intensities so that made me suspicious. The Eu L series (of electron deexcitation) consists of several peaks, of which some are more prominent than others. The EDS analysis program fits the curves to an analytical function in order to render possible a quantitative analysis. According to the curve fit, the last peak at about 8.0 keV does not belong to the europium peaks - instead it fits quite well with the energy of Cu K alpha, but I'm starting to suspect that, in fact, it does, but is simply overlooked by the program - possibly because people normally don't have so much europium in their samples... I know that the L gamma peak is split but I don't know into how many peaks; also the program doesn't make any difference between the gamma peaks. Does somebody have a good reference here where one can see clearly which peaks belong to europium? - how many L alpha, beta, gamma etc. peaks are there, and at what energies? I've been able to find some info on relative intensities but that doesn't help without the positions on the energy scale. E.g. för the EuM peaks I see that one peak is always exaggerated compared to the theoretical intensity and another peak is always too low. So could somebody give me a reference with a graph, or a table of fluorescence energies?