Hi Lisa,
On Mon, Oct 26, 2009 at 9:12 PM, Gudrun Lisa Bovenkamp
I am sure that Athena was tested a lot, but as Jeremy pointed out, which I think now is the answer: If the background is substracted before the fitting of the post edge. That is actually how we are normalizing XANES data in our group and that is what I tried in Athena. It is actually working much better with 2. order norm and flattening.
If you're concerned about normalization, do not flatten the data!!!
This time I attached a the example Athena project file.
I did not look closely at all the data in your project file, but the first group listed "Pb113 norm in Athena" has E0 = 13037.76. Extracting the mu(E) data, and looking in the region around E0 + 200 eV, I see these energy values: 13233.508 13235.121 13236.630 13238.452 13240.066 so that, in fact. there are no data between E0+199 = 13236.76 eV and E0+200 = 13237.76 eV.
But with this approach I rarely get the spectrum oscillating around one.
Actually, you're not supposed to get a spectrum that oscillates around one. Again, you will get a better normalization if you use a line (Normalization order=2) and a range of 100 to 250eV. When I do this with the "Pb113 norm Athena" and "Pb125 norm in Athena" data in your project, I get a mu(E) that starts out ~1 and decays away with energy, just as it should. The "norm in Orign" groups you have in your project all have about the same value for mu(E) at E=E0+200eV, but are not well normalized. --Matt