[Ifeffit] Athena bug and a question

[Bruce Ravel]

On Wednesday 18 October 2006 12:00, Silvio Levy wrote:
> Bruce - thanks a lot for your post.  I've encountered this bug a few
> times, but I thought it might be a problem with my machine; in any
> case I could never replicate the problem and file a bug report.

Silvio,

The workaournd in the FAQ is not thoroughly tested, but I am pretty
confident.  If you still see the problem, let me know in personal
email and I can give you a copy of the next version of Athena to try.

As for the spike at low-k -- I dispute that the normalization is
effected.  The nromlaization is betwermined not using the background
function but by regressing a line to post-edge region.

That said, you most certainly have a spike at low k.  I think the
situation improves somewhat (without changing chi(R) significantly
since the FT range starts at 2.5 in your project file) by making the
lowr bound of the spline range 0 AA^-1 and making the k-weight for
background removal equal to 2.

And, of course, what Shelly said about using a standard is an
excellent idea.

B


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