## Appendix A Signal-to-Noise for EELS and EDX  
The signal-to-noise for both EELS and EDX can be described when taking only counting statistics into account where the noise is determined by the square root of the total signal (signal and background) [34; 35]. \[SNR_{EELS}=\frac{C\sigma\cdot\sqrt{\epsilon_{e}It}}{\sqrt{C\sigma+B_{e}}} \tag{1}\]  
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