I've been developing protocols for doing standards based EDX analysis in my lab using DTSA-II. We have a Tungsten filament SEM with a 30mm Bruker SDD. The problem, my SEM not being a probe, is that the Faraday cup is a bit of a hike from my sample.
I've set up the system to monitor probe current over long timescales a couple of times to get a feel for what I'm dealing with (plot attached). On an hour long interval, it looks more or less linear.
So, the question is this: Is it acceptable to read the probe current, collect for 10 minutes, then read the probe current again, and assign probe current start and end values to the collected spectra using a linear interpolation between the points tied to the timestamp? Assume a sanity check for accepted probe current rise or fall is in place to catch transient spikes or dips as well as an appropriate warm up time of 30 minutes for the gun to stabilize.