Hi there,
I have a question about this. This is how a spectrum of UO2 looks like on our 1011 Qtz crystal high pressure spectro (2 bars P10).
![](https://probesoftware.com/smf/oldpics/i58.tinypic.com/vnnll1.jpg)
![](https://probesoftware.com/smf/oldpics/i61.tinypic.com/kajswn.jpg)
So we have the Ar absorption edge on the short wavelength side of the U Ma peak.
1) how does this work with this stupid edge? I mean, in the sense of: Looking at the other posts in this thread, it affects also the background intensity. Is that the case for the whole "right" side of the spectrum? Will the intensity of the background be lower than on the "left" side for the rest of the spectrum? I am asking this, because I am thinking about where to measure the background for U Ma here. It is clearly super high on the short wavelength side.
2) So wouldn't it be a good idea to use the multi point background method? Like shown in the image? I would measure the backgrounds left and right of the whole are of U M lines and put some exponential fit through. However, what about this absorption edge then? Imagine how this area looks like in a sample where we have U, Np, Pu, and Am. It's like the REEs, just worse. I think the multipoint option is the only reasonable approach, whatever there is with the absorption edge of Ar.
3) Another question in this respect: Is it possible to correct for the Ar absorption? Let's say I would know exactly the ratio of the U Ma-Mb second order, would that be the same ratio as for the U Ma-Mb first order? Or would it be better to compare to the ratios of Np or Pu Ma-Mb? Or, in addition, could I "correct" for the Ar edge to bring the Th Ma line up to a level where I could compare it to Np Ma or Pu Ma?
What do you think?
Cheers
Ph