Micromass Quattro Ultima, User Manual

Page: 128 / 227

When an instrument acquires data for a static calibration it first examines the
selected reference file for the expected reference masses. It then acquires data
over a small mass span around the expected position of each peak. Thus the
acquired data do not contain continuous scans, but each “spectrum” is made up
of small regions of acquired data around each peak separated by blank regions
where no data are acquired.
Static Span
sets the size of this small region around each reference peak. A value of
4.0 amu is typical.
Static Dwell determines how much time is spent acquiring data across the span. A
value of 0.1 second is suitable.
Slow Scan Time
and
Fast Scan Time
are not available when a static calibration
alone is selected.
Select OK from the Calibration Acquisition Setup to return to the Automatic
Calibration dialog box.
Acquiring Data
To start the acquisition:
Select
OK
from the Automatic Calibration dialog box.
The instrument acquires a calibration file ready for static calibration using the data file
name STAT. While data are being acquired:
Inject the reference solution.
Once the data have been acquired the instrument attempts to produce a static
calibration automatically. The data file contains only a few scans of the reference
compound, the remaining scans being of background.
As the automatic calibration procedure combines all of the scans in the data file to
produce a calibration spectrum, the resulting spectrum may be too weak to give a
successful calibration. Whether the calibration is successful or failed, it is wise to
check the calibration manually.
Mass Calibration
Page 128
Quattro Ultima
User's Guide