There seems to be some confusion regarding how PFE quantifies elements using EDS.
I've searched through the forum and not found a direct answer.
It is my understanding that PFE takes the net counts from "unknown" spectra and standard spectra from Pathfinder/NSS. That is to say that PFE takes the counts for the X-ray lines of the element of interest after Pathfinder/NSS accounts for sum peaks and escape peaks, removes the background, and deconvolves any interference. Is this understanding correct?
Furthermore, does PFE rely on the factory peak shapes in Pathfinder/NSS for deconvolution of the spectrum for extracting net counts, or does PFE load standard reference shapes into Pathfinder/NSS so that user-acquired standard spectra are used for deconvolution?
Thanks!
Hi Steve,
No that is not correct. PFE performs EDS quant just as WDS quant is performed. Specifically using a full k-ratio. That is, both EDS spectra on unknowns *and* standards are acquired, and PFE then sends the spectrum for the unknown *and* standard to Thermo (or Bruker) to obtain the net intensities on both, then constructs the k-ratio and then runs those EDS k-ratios through the quant (what ever it might be), along with the WDS k-ratios.
Because of this one obtains the most accurate quantification because each EDS element has a reference standard. In addition, we can also apply spectral interference corrections to both EDS and WDS elements (WDS by WDS, WDS by EDS, EDS by EDS and EDS by WDS!).
As for peak shape profiles, those can be defined in an NSS project and specified when PFE makes a connection to the EDS interface. With Bruker one can specify a peak profile separately for each sample, while Thermo applies the peak profile on a per project basis.
So the bottom line is that PFE only utilizes the peak stripping routines in Thermo or Bruker EDS to obtain the net intensities. The option to specify a Bruker "quant method" for dealing with peak shape fitting is shown here:
http://probesoftware.com/smf/index.php?topic=578.msg3305#msg3305For Thermo, when one connects to the Thermo Portal Server, PFE asks:
![](https://probesoftware.com/smf/gallery/1_17_12_16_12_33_52.png)
See here for details:
http://probesoftware.com/smf/index.php?topic=482.msg2826#msg2826and also here:
http://probesoftware.com/smf/index.php?topic=79.msg3005#msg3005I've also attached our EDS-WDS PPT filpe that I presented in May at the Madison TC below (login to see attachments).
john