User`s guide

Chapter 6 Acquiring Mass Spectra

6-16 PerSeptive Biosystems

During

acquisition

During acquisition:

• The Live/Current Spectrum trace in the Spectrum window

updates to display the spectrum that results from each

laser shot.

NOTE: If your system includes an oscilloscope, the

Current Spectrum does not display a trace until

acquisition is complete. The spectra that result from

each laser shot are displayed on the oscilloscope

screen.

• The system averages all spectra acquired since you

started acquisition.

When acquisition is complete, the software displays the

averaged spectrum in a Current trace in the Spectrum window.

Evaluating data

As data is acquired, observe the trace in the Spectrum

window:

1. Examine the number at the top of the right axis in the

Current Spectrum trace to determine if signal is

saturated (Figure 6-4). Signal with counts greater than

64,000 may be saturated. Adjust the laser intensity as

needed.

For information, see “Signal saturation” on page 5-59.

2. Use the Resolution calculator or the Signal-To-Noise

calculator on the Current trace to determine if data is

acceptable. For more information see Section 6.5,

Evaluating Data in the Instrument Control Panel.

Hint: You can accumulate traces to improve resolution

and signal-to-noise ratio. For more information, see

Section 6.2.2, Manually Accumulating Spectra

from Multiple Acquisitions.