My intention is to do combined ED-WD quant analyses. Are the EDS-acquired elemental calibrations handled/stored in PfEPMA or do they need to be set up/calibrated in the NS7 software?
Hi David,
When PFE performs "integrated" EDS-WDS, it really is truly integrated. That is, for every WDS analysis point, there is a corresponding full EDS spectrum acquired at the same time. Therefore, in Probe for EPMA, your standard EDS spectra are collected and stored just like your unknown EDS spectra.
At analysis (not acquisition) time, the app retrieves and sends the full spectra to have net intensities extracted for specific elements for *both* the standards and unknowns. Then a full k-ratio is calculated and run through the specified matrix correction routine together with the other WDS elements.
Two points here: one, you don't have to decide in advance what elements you want to analyze by EDS and two, this way you get a self consistent matrix correction applied to both WDS and EDS elements.
Based on recollections from my Bruker EDS days on the UTasmania CAMECA SX100, what specific info (peak cts, bgd cts, net peak cts, etc etc....) does PfEPMA collect/need from the EDS system/software? That is, how much 'setup' is needed on the Thermo Noran system and how much of it is done/handled in PfEPMA??
Probe for EPMA handles everything. That said you can certainly force different pulse processing speeds in the NSS software and there is even an option in PFE to just use the default EDS acquisition time, even though you can specify that in PFE also.
Note: when specifying the EDS acquisition time here:
That the specified acquisition time is "livetime", that is, without the deadtime. Therefore, if your DT is 50%, then your EDS acquisition time will be approximately 1.5 times longer than you actually specify- again, this is dependent on the beam current and even sample composition to some extent.
My memory re the Bruker-CAMECA combine is that I had to set up the Bruker carefully as PeakSight only called net counts (or cps?) for each element acquired by ED for quantification. The ED std calibrations themselves were performed and stored within PeakSight...
Yes, that is true for the Bruker-PeakSight situation, however, since we store the full EDS spectra, that is not an issue for Probe for EPMA when integrated with either the Bruker or the Thermo systems.
David Rohde from Thermo USA is currently here and has installed the Ultradry detector (very nice!! 124eV FWHM at MnKa, 35eV at B Ka) and NS7 software. He's doing 'training' for the rest of this week.
Sounds like fun, please say "hi" to David R. for me...
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