Count rates from X-ray Fluorescence Spectrum

[hhhmortal]

My question is, when extracting the count rate from a particular peak in the energy dispersive spectrum (e.g. X-ray fluorescence) Is this done by simply drawing a straight horizontal line from the top of the peak to the y-axis and the corresponding intercept will be the count rate? What if the peak has a large spectral width (i.e. large FWHM), does this change the count rate for that peak?



Thanks

 

[hhhmortal]

Can anyone provide a yes or no answer at least? :/

 

[SpectraCat]

Sorry .. missed your post before. Anyway, I think you need to integrate the peak to get the total intensity. Basically, if you just draw the line you described, I think you would only know the count-rate at max intensity. I am not that familiar with X-ray fluorescence data, so I can't really say more than that off the top of my head. I don't know the conventions of the field for describing data to others. It is possible that the count-rate at max intensity is the proper way to report data ... that can sometimes be just fine if all your peaks have the same shapes and the peak width is constant (or at least doesn't change much). However if you are comparing peaks or spectra with drastically different peak-widths, then it doesn't seem correct to mention only the max count rate.

Are your peaks gaussian or Lorentzian shaped, or are they some other shape entirely?

 

[hhhmortal]

They are gaussian. I'm just curious how this is done in practise. I assume as you mentioned, the gaussian is just integrated to get the total count rate. Of course the smaller the FWHM the more accurate it would be to just read the count rate at max-intensity.Thanks, this has helped!

 

[SpectraCat]

They are gaussian. I'm just curious how this is done in practise. I assume as you mentioned, the gaussian is just integrated to get the total count rate. Of course the smaller the FWHM the more accurate it would be to just read the count rate at max-intensity.


Thanks, this has helped!

Glad to help .. just one additional point that might need clarification .. it doesn't matter so much if the peaks are narrow or broad, what matters is that they all have the same width (within some acceptable tolerance). Since the peaks are gaussian, if they all have the same width, then the ratios of their areas are identical to the ratios of their maximum heights.