The Digital Gamma Finder (DGF)
family of digital pulse processors feature unique capabilities for
measuring both the amplitude and shape of pulses in nuclear spectroscopy
applications. The DGF architecture was originally developed for
use with arrays of multi-segmented HPGe gamma-ray detectors, but
has since been applied to an ever broadening range of applications.
With a general and highly programmable design for digital signal
capture and processing, coupled with a flexible triggering system
that can span multiple modules, the DGF is a powerful instrument
that works directly with a wide variety of x-ray, gamma-ray, and
particle detectors.
- Simultaneous amplitude measurement and pulse shape analysis
for each channel.
- Pulse heights measured with up to 16 bits accuracy with the
Polaris (i.e. 64K spectrum length).
- ADC sampling rates up to 100MHz with the Pixie-16
- Module-to-host transfer rates up to 109MB/s with the Pixie-4
- Dead times as low as 1 microsecond per event are achievable
(limited by DSP algorithm complexity). Events at even shorter
time intervals can be extracted via off-line ADC wave form analysis.
- Digital constant fraction algorithm measures event arrival
times down to a few ns accuracy .
- Programmable gain, input offset, and peaking times between
0.25 and 40 microseconds.
- Programmable pileup inspection criteria include trigger filter
parameters, threshold, and rejection criteria.
- Analog type multiplicity input and output can be daisy chained
across multiple DGF modules.
- Supports multiparametric data acquisition of events distributed
over many detectors as well as independent spectrum acquisition.
- Waveform capture up to 100 microseconds in length for each
channel.
- On-board MCA memory for data taking or for monitoring when
in multiparametric mode.
- External fast first-level event trigger ("GFLT"
or gate) and delayed second-level trigger ("GSLT"
or validation) facilitate complex data acquisition system construction.
- Simultaneous data run start and stop across many DGF modules
via "Busy out" and "Sync in".
- Common dead times across all modules via "Trigger out"
and "GFLT in".
- Clocks can be synchronized for all DGF modules in a system.
In multiparametric mode, events are time stamped for off-line
identification and relative time measurements.
- Supports 16 bit Level-1 FAST CAMAC transfers (5 Mbytes/second).
- Optional Data readout via IEEE 1394 (Firewire) interface.
The DGF comes in four standard implementations, and can be customized
for OEM customers.
Pixie-4 Modules are PXI (Compact
PCI) 3U standard modules comprising 4 integrated DGF channels.
These are the new building blocks for scalable multi-element detector
instrumentation systems.
Pixie-16 Modules are PXI (Compact
PCI) 6U standard modules comprising 16 integrated DGF channels.
DGF-4C Modules are NIM standard CAMAC
modules comprising 4 integrated DGF channels, with sophisticated
timing inputs and outputs.
DGF Polaris Modules comprise a
standalone DGF channel with integrated 5kV detector bias supply
and preamplifier power.
DGF-OEM Modules are custom and semi-custom
DGF circuit boards suited to fit the needs of larger customers under
OEM contract.
Further online information:
- To learn more about the Digital Gamma
Finder topology, its applications and history, please visit
the DGF Introduction page.
- The DGF software
page contains description of the host applications and drivers
available from XIA.
- The user
resources page contains links to software and firmware downloads,
datasheets, manuals and other documentation.
- The support
page describes common problems and solutions
|
