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formulaphysicsdm-script

How can I automatically get both the signal and error from edges in EELS spectra?


Is there some DM-script function, or any other way, to obtain both the signal integral and the error of the signal integral from a Spectrum-Image or series of background-subtracted EELS Spectra?

I am analysing a series of EELS spectra in DigitalMicrograph. I use the normal tools in DM to get the signal counts in the different windows after background subtraction. When I analysis the spectra one at a time (for instance with EELS\Quantification…, and selecting “single spectrum”), I get the estimation of the error in addition to the spectrum signal.

For instance I get: Signal (counts): 2.91e+004 ± 1366.

However, if I analyse the full series of spectra in a spectrum-image or a spectrum-line (SI\Map\Signal(Dynamics)… or with ELLS\Quantification, but selecting parent spectrum-image), I am not able to obtain the errors, I only obtain the signal counts.


Solution

  • There is no script-access to this functionality. However, one can easily do the maths oneself.

    The error given in the EELS analysis (GMS 2) is just the uncertainty from the detector readout calculated by Poisson statistics, i.e. Sqrt(N) where N is the integrated intensity of the according energy region (before background subtraction). If intensity calibration is present, it is taken into account.