Fitting and Subtraction of Background

In the area of expected amorphous humps (also for very great 2Q 120° the background may increase again) one can admit a minor increase of the background above that of adjacent points by about -2g, i.e. omit the substitution by the estimated value (or substitution only if the original 

Another method for fitting the background is used by the program EVA of Bruker AXS. Here parabolas with a variable curvature (set by the user) are shifted upwards from below the pattern until they touch the background. The envelope of all these parabolas is then taken as background curve. 

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