[Ifeffit] Could you please give me some information?

[Bruce Ravel]

On 02/01/2016 11:58 PM, pinit wrote:
> Dear Bruce,
>
> I am Pinit from SLRI, Thailand. I have some questions concerning the
> Si-drift detector.
>
> Could you give me some suggestions if Si-detector can detect the
> corrected Si K-edge or not? This is because I have seen a significant
> EXAFS signal (higher in amplitude in FT) measured by Si-drift detector
> differs from Lytle detector or ionization chambers (TM mode).

Hi Pinit,

Nice to hear from you.  I am CCing my answer to the Ifeffit Mailing
List.  Someone else may have more insight into your question than I
do.  You should CC the list in your response.

I'd probably need to know more about the sample and the nature of the
measurement you made to understand why you are seeing a different
signal with the Si drift detector.

Normally one would expect that he EXAFS would be /attenuated/ either
due to self-absorption or due to the energy dependence of the I0
detector.  That you are seeing a larger EXAFS signal with the Si-drift
seems surprising.

One thing that occurs to me is that the Compton and elastic peaks
probably overlap the Si K alpha ROI quite a bit, even extending into
the EXAFS region.  I would have thought that, too, would serve to
attenuate the EXAFS (but maybe I am thinking about that wrongly).

Perhaps it would help to show us some of the data...?

B




-- 
  Bruce Ravel  ------------------------------------ bravel at bnl.gov

  National Institute of Standards and Technology
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