[Ifeffit] Find white line position
Bruce Ravel
bravel at bnl.gov
Thu Aug 2 06:41:15 CDT 2018
It's not very sophisticated.
Starting with the "flattened" spectrum (see
http://bruceravel.github.io/demeter/documents/Athena/bkg/norm.html#the-flattening-algorithm),
it simply finds the highest point in the spectrum. Literally just the
ceiling function.
The flattened spectrum is used rather than the normalized spectrum
because the curvature of the post-edge (or even the curvature of the
pre-edge in fluorescence data with a energy dispersive detector) could
result in other regions being higher in value than the white line.
This is a pretty horrible algorithm. It is, I think, guaranteed to find
an obviously wrong point for a metal. Basically it works for spectra
with a white line and it will almost certainly fail for spectra without
a white line.
Use with caution!
HTH,
B
On 08/02/2018 01:28 AM, Hiroshi OJI wrote:
> Dear all,
>
> I have a question about one of the useful function, "find white line
> position" in Athena.
>
> Could anyone tell me how Athena find the white line position by this
> function? In other words, I would like to know the algorithm to find the
> white line position in Athena.
>
> Thank you very much for your help, in advance.
>
> Best regards,
>
> Hiroshi Oji
>
>
--
Bruce Ravel ------------------------------------ bravel at bnl.gov
National Institute of Standards and Technology
Synchrotron Science Group at NSLS-II
Lead Beamline Scientist, 06BM (BMM)
Building 743, Room 114
Upton NY, 11973
Homepage: http://bruceravel.github.io/home/
Beamline: https://www.bnl.gov/ps/beamlines/beamline.php?r=6-BM
Software: https://github.com/bruceravel
Demeter: http://bruceravel.github.io/demeter/
More information about the Ifeffit
mailing list