Dear members of the Ifeffit list, I recently collected some EXAFS data with some significant monochromator glitches that I am looking to remove. I have used a python script graciously written by the beamline scientist to remove the offending regions, but when I import the data into Athena, Athena does some funny business in an attempt to join together the regions outside of the data gap. (See the bending away in the dataset and/or attached image.) I have confirmed by plotting with other software that the strange step-like behaviour in the mu(E) is present only after importing into Athena (the raw data is fine).
I have looked through the mailing list archives and also the user manual, but can't seem to find anything that explains it, or other people who have experienced this problem in the past. From what I can determine, Athena joins together the segments to obtain a linear interpolation in the norm(E)? This leads to a warping in the mu(E). ==How does Athena try to treat this data?== I was wondering if other people have had similar issues, and what steps can be taken to remedy the problem. For example, replacing removed data points with artificial points along a linear interpolation would be possible, but the act of adding artificial points that don't exist is concerning to me. ==What is the best way to treat data with mono glitches to reduce spurious features not intrinsic to the sample?== If you are interested, I have included links to .prj datasets and images to highlight these problems below. With thanks for your time, Michael ---------- .prj file with 4 ways of working up the same data: http://bit.ly/2bnfNZ5 1) raw data 2) mono glitches removed 3) rebinned data 4) rebinned and manually removed points (This leads to some strange-looking features in k-space, and this would be less than desireable on the many datasets we have collected) images to highlight these problems: a) mu(E) http://bit.ly/2aYaJIf b) norm(E) http://bit.ly/2aYaX27 c) k http://bit.ly/2baWh0h
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