- 100MHz, 12-bit digitizing of input signal
- 32bit/33MHz PCI interface with module-to-host transfer rates up
to 109MB/s
- Simultaneous amplitude measurement and pulse shape analysis for
each channel
- Pulse heights measured with up to 16 bits accuracy on each of the
four channels
- Waveform acquisition up to 40us for each channel, in 10ns intervals
- 32k x 32bit on-board spectrum memory for each channel
- 128k x 16bit additional on-board FIFO memory for continuous readout
of list mode data
- Fixed gain, adjustable input offset, trigger and energy filter parameters
- Coincident data acquisition across channels and modules
- Triggers, run synchronization and clocks distributed over PXI backplane
- Graphical user interface and C-based driver libraries
- Operated through in-crate single board PC or through fiber optic
link from desktop
- Can be combined with commercial CompactPCI/PXI processor, power,
and computer modules
The Pixie-16 can operated through XIAs host control
software or by integrating C libraries into existing user acquisition
software. Users can set all parameters relevant to the data acquisition,
store them in settings files, and run the modules. Results can be displayed
from data files to provide instant feedback on the state of the experiment.
XIA’s host control software provides several
diagnostic tools for setting up a new system. There is a display of
triggered and untriggered waveforms as they are seen by the Pixie module.
The waveforms can also be subjected to a fast Fourier transformation
(FFT). These displays are useful to investigate if there is any electromagnetic
interference in the system, from 50/60Hz to radio-frequency pickup.
For system setup, users can employ automated tools to determine the
decay time of the preamplifier and to set the offset to a specified
fraction of the dynamic range.
Experiments that run their own data acquisition
software can use XIA’s driver (written in C) to integrate Pixie
modules into their system. Module setup, start and stop of runs, and
data readout can be performed using a small number of functions. The
Pixie Viewer is based on the same driver and can be used as a programming
example.
A basic data acquisition system can consist of
an 8-slot CompactPCI crate with integrated preamp power supplies, one
Pixie module, a single board host computer and a high voltage module.
The host computer is used to download software and settings to the Pixie
module, start and stop runs, read out the data and write it to disk.
Instead of a single board computer residing in
the CompactPCI crate, a regular desktop or laptop computer can act as
a remote crate controller using a set of adapter cards with a high speed
copper or fiber optic data link. Data readout speeds are equivalent
for local and remote controllers.
For bigger detector arrays, a larger PXI crate
(up to 14 slots) can be used. One or more slots can be occupied by commercial,
user-programmable DSP processor modules to process data for event reconstruction.
High speed I/O modules can be added, either on the DSP modules or in
a separate slot, for fast data readout from the Pixie front end electronics
to external data processing computers.
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