On Sun, Apr 3, 2016 at 6:56 PM, Matteo Busi <basebush@gmail.com> wrote:

Hi Bruce,
Thanks for your help, it's really appreciated.
I was trying to keep it simple but it seems I'm just messing around.

What I am trying to do is to perform a new developed self-absorption correction using collected fluorescence absorption coefficient data on a CuSO4 (pentahydrate) capillar (cylinder) and spherical sample with Cu as absorber, having different values of molarity and penetration depth.
The correction expression requires these measured quantity:
μX(E) : the absorption coefficient due to a given core excitation of the absorbing atom
- I used the background function for this ( bkg(E))

Wouldn't using bkg(E) suppress the fine-structure you are trying to recover? Anyway what are the units, are you normalizing bkg(E) to something meaningful? I would suggest using data from Chantler or Cromer-Liberman here. Or perhaps match mu(E) or bkg(E) to these.

μo = μ(E) : photoelectric total linear absorption coefficient of the sample at incident energy E
- I used the xmu(E) for this

Again, be mindful of what the units are.

μh = μ(E) :photoelectric total linear absorption coefficient of the sample at fluorescence emission Ef
- I used the xmu(Ef) with Ef the K absorption edge of Cu ( 8.9789 eV)

I am pretty sure that this is not what you want. You probably want mu(E) at the Cu fluorescence energy (8.046 keV). This can make a significant difference.

HTH,

--Matt