Mapping Panel: List-Mode Data Acquisition; List Mode Variant - National Instruments NI PXI-1042 Quick Start Manual

STJ Quick Start Guide v 2.01
Enter the desired Calibration Energy and Acquisition Time(s). Note that the Acquisition Time
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should be sufficient, based on the Input Count Rate, to acquire a peak whose Mean and FWHM
can be measured; a few thousand events are typically necessary and sufficient.
Fig 13: The GainMatch panel for a 32-channel system with Channel 15 disabled, after the Gain Matching sequence has been
executed. Note that the Acquisition Time is 3 seconds, which corresponds to 3,000 counts at 1 kcps. Note that the Lower and
Upper fields were set conservatively to select the built-in pulser peak at roughly 1 keV on all channels. Note that the data for
channel 15 has been omitted, as indicated by the red 'X' in the Channel display area. Finally note that the resulting data in the
Energy histogram shows all channels calibrated to 1 keV, per the Calibration Energy (keV) setting.

MAPPING PANEL: LIST-MODE DATA ACQUISITION

The Mapping panel is used for list-mode acquisition, e.g. each event generates an event record with
channel ID, time-stamp and energy value. Event records during a run are saved to a binary file.
Please refer to the STJ List Mode Specification for further details on the different list-mode
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options, and the event record, buffer header, and binary file formatting.
Some of the labels may be confusing on this panel, because it also supports other 'mapping' or scanning
modes for other products and applications. The term "pixel" refers an event on any channel, so the Total
Number of Pixels setting constrains the total number of events on all channels.

LIST MODE VARIANT

Perhaps the most important setting is the 'List Mode Variant', which defines the type of information
stored in the output binary file, as described in the STJ List Mode Specification. At present, this setting is
not directly accessible in the Mapping panel.
To change the List Mode Variant, open the DSP Parameters... window accessible under the
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Tools menu, as shown in Figure 14 below. Edit the integer value for LISTMODEVAR and press
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April 1, 2021