[Ifeffit] Fwd: Athena troubleshooting

[Bruce Ravel]

I am forwarding this message to the Ifeffit mailing list, which is the
proper forum for Ifeffit software support.  Please see
  http://cars9.uchicago.edu/iffwiki/BruceRavel/FormLetters/HelpRequest

I have some comments, which I will post once this gets distributed by
the mailing list.

B


----------  Forwarded Message  ----------

Subject: Athena troubleshooting
Date: Wednesday 07 October 2009
From: Tom Malizia <fezzooli at gmail.com>
To: bravel at bnl.gov

Hello, this is Tom Malizia.  I'm a master's student from the University at
Buffalo, and my advisor (Tracy Bank) and I have been granted access to use
beamline  X11A for the student teacher program.  Anyway, I'm emailing
because I'm having some trouble with how to manipulate my data and interpret
the results.
I have run 14 samples (each 4 times) on the beamline, and I'm looking for a
shift in the oxidation state of Uranium (4+ to 6+).  I'm not sure and can't
seem to find any literature on how significant the shift must be to prove
anything.  Of the 14  samples the uranium peaks for almost all are the
samples are at 17160 eV, however a couple samples are at 17158 and another
at 17159 eV.  The beamline was filtered for both Thorium and Strontium and a
zirconium foil standard was implemented.  I have aligned all of the
zirconium standards peaks, and still have this slight shift in the energy of
uranium. Do you have any insight?

Also, this is more of a software question.  I'm not sure why, but about half
of the samples flip their orientation 180 degrees (from positive y to
negative y) when "normalizing" them.  But when I'm trying to display several
samples at once about half are showing positive peaks and half are negative
peaks.  For instance, samples 10, 3 and 1 don't flip when normalized,
however all of the other samples do.  If this isn't a good enough
explanation I could send files or we could trouble shoot over the phone.
 I'd like to show as much as I can at the upcoming GSA conference next
weekend.  I appreciate your time.

Thanks so much
Tom Malizia
University at Buffalo
814-594-4281 cell

-------------------------------------------------------

-- 

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

 National Institute of Standards and Technology
 Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2
 Building 535A
 Upton NY, 11973

 My homepage:    http://xafs.org/BruceRavel
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