Truncating a Spectrum

The data in the spectrum is truncated to the selected range and is displayed with a TR trace label. The range displayed on the axis of the truncated trace is the range of the original data file, and may be wider than the range of the truncated spectrum.

6.To return to the original trace, see “Returning to the original spectrum” on page 5-3.

Example Figure 5-18and Figure 5-19illustrate the effects of truncating a Voyager spectrum and eliminating the Low Mass Gate peak.

Figure 5-18includes a Low Mass Gate spike. Because the Low Mass Gate spike is the most intense peak in the spectrum, it is identified as the base peak, and:

•All other peaks in the spectrum are scaled as a percentage of the base peak.

•A default peak detection threshold, %Base Peak Intensity, is set to 1 percent of the base peak. One percent of an intense peak yields a high default threshold, and many peaks in the spectrum are not detected.

Low Mass Gate spike

Figure 5-18 Complete Spectrum with Low Mass Gate

Spike

Figure 5-19shows the spectrum truncated to eliminate the

Low Mass Gate spike. The peak at 3772 Da is identified as the 5 base peak, the %Base Peak Intensity is set to a lower value,

and more peaks in the spectrum are detected.

Data Explorer™ Software User’s Guide

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