Process that Occurs During Peak Detection, Centroiding, and Integration

After peak detection

Centroiding

After peaks are detected:

•Centroid mass is calculated for spectral data, then modified by Gaussian peak fitting, if it is selected.

•Chromatographic and spectral peaks are integrated.

•Peak lists are generated for chromatograms and spectra.

The Data Explorer software calculates the peak centroid for spectral data by:

•Drawing a projected centroid baseline at the percentage of the peak height specified by the Centroiding% entered. Centroiding is measured between the top of the peak and 0. For example, a centroiding% of 10 uses the top ten percent of the peak, where peak height is determined from 0.

•Searching to the left and right of the apex for data points that bound the projected centroid baseline, then

interpolating the centroid baseline.

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•Calculating the intensity-weighted area of the peak from the left to the right intersection of the centroid baseline, then dividing by the area of the same region.

Data Explorer™ Software User’s Guide

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