May be it is relevant... I use references to align the data in energy, not to measure energy shift between different samples, because the references may be (not always are though, but why to take chance...) inherently worse quality data compared to the bulk of the relevant standard compound that I want to compare with my sample. For the purpose of aligning 10 scans before averaging (merging) them, their respective reference files are aligned, and no merging is needed. Then, if I want to find a shift between the unknown sample and a standard compound (say metal foil) I align 10 scans not relative to the reference taken for the first scan, but relative to the standard compound measured in transmission in some prior experiment, or during the same experiment but as a separate measurement. Of course, if Pt foil is the standard compound then Pt foil should also be a reference used for alignment. Then, the 10 samples are aligned correctly (and can be merged), and the merged data can be compared directly to the standard compound that is conveniently located in the same Athena project. Thus, no merging of references is needed. Anatoly ________________________________ From: ifeffit-bounces@millenia.cars.aps.anl.gov on behalf of Scott Calvin Sent: Thu 11/19/2009 1:48 PM To: XAFS Analysis using Ifeffit Subject: Re: [Ifeffit] Bug in Athena? Hi Bruce, On Nov 19, 2009, at 11:48 AM, Bruce Ravel wrote:
Why does Athena make a merge of references? As Matt points out, that is an odd thing to do.
I may be confused as to what we're talking about. Why is this an odd thing to do? It seems perfectly normal to me to want the reference scans merged as well as the sample scans, in order to get a clean measure of chemical shift. --Scott Calvin Sarah Lawrence College _______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit