Canberra Lynx DSA, Руководство пользователя

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Chapter 5 Web-Based Operations
146 Lynx DSA User's Manual - 9240227J
MULTISPECTRUM SCALING (MSS)
If configured for MSS data acquisition, the Lynx acquires data into its two PHA
memory groups in a “ping-pong” fashion – acquiring alternately into one group while
the other group is stored to computer and cleared. If a group has not finished clearing
when it is time to switch groups, acquisition continues in the first group until the
second group is ready to receive data.
Minimum count time with no data loss between acquisitions is 100 ms limited by the
host computer’s ability to process and store the data such that it can be cleared from
Lynx memory and the memory reused for the next acquisition.
DUAL LOSS FREE COUNTING (LFC)
Dual Loss Free Counting (DLFC) mode allows accumulation of a loss-free corrected
spectrum simultaneously with an uncorrected spectrum. Analysis of the two spectra
together allows more accurate quantification of the data than analysis from a single
spectrum.
Peak centroid (energy), net area, background and counts per second are computed
from the corrected spectrum, while the uncertainty in the computed peak area is
derived from the uncorrected spectrum. This results in a better estimate of the error
than if the computation were performed using the corrected spectrum (due to the non-
Poisson nature of the corrected spectrum).
List (LIST) and Time-Stamped List (TLIST) modes
Note: The List modes (LIST and TLIST) of operation may require special
engineering or assistance for the communication libraries involved. Contact
your local representative concerning this feature. A sample program is
provided with the Software Development Kit (SDK).
ADC events are stored sequentially (similar to a list) in the Lynx’s buffer memory in
the order received from the detector, until the buffering is exhausted or read and
processed by a client application.
The Lynx can be programmatically set to stream (or push) LIST data to listening
client(s) on a periodic basis; this method (streaming) eliminates the overhead of the
internal buffering.
All LIST and TLIST data produced by the Lynx consist of 32-bits per event.
During LIST/TLIST acquisition, digitized energy events from the fast ADC are
recorded by the Lynx in the order received from the detector. For LIST mode, only
the energy component of the event is stored by the Lynx. For TLIST mode, both the
energy component and the associated time stamp for each event is recorded by the
Lynx using 1.0 µ Sec or 0.1 µ Sec clock resolution