- Single and Dual 32k Digital MCA & Pulse Processor
- Fully supported by Quantus High Performance Quantitative Spectrometry Software
- Provides Pulse Height Analysis (PHA with MSS* and coinc/antocoinc), Time-stamped Lists and Multichannel Scaling (MCS*) modes
- Ideally suited for high resolution spectroscopy applications utilizing HPGe, CZT, Silicon, and scintillation detectors such as NaI and LaBr3
- Supports Resistive Feedback and Transistor Reset preamplifiers as well as PMT anode signals
- User-selectable DC or AC Coupling (includes software-selectable time constants for input rate matching)
- Equipped with Digital I/Os for multiple functions (PHA start/stop, SCA, ICR, MCS start/stop, MCS Advance and Sweep)*
- BNC connector specific for TRP inhibit or ADC gate on each input
- Two triple-range, hardware protected, HVPS channels managed by software to match bias to specific detector types (PMT, HPGe, Silicon)
- Two DB9 connectors provide ±12 V and ±24 V to power preamplifiers as well as a dedicated input for Detector Temperature feedback
- Digital and analog signal inspector (waveforms and filters) for a fast setup and multi-trace monitoring
- Includes auto-set pole/zero compensation, baseline restore, pile-up rejection, and live time correction capabilities
- SATA connectors for system building and multi-board synchronization
- Front panel OLED Display for diagnostics and statistics
- On-board SSD memory supports List and Spectrum data storage capability (up to 200,000+ spectra)
- On-board user-accessible ARM processor running Linux OS enables user to develop custom processing routines and supports 100% unattended operations
- Software Development Kit (SDK*) for both host PC environment and Hexagon embedded Linux environment
- Web interface for quick retrieval of board details, firmware upgrading, and output data file browsing
- 10/100T Ethernet and USB 2.0 readout intefaces
(*) Coming Soon
Hexagon is a stand-alone, single or dual digital 32k MCA, integrating input stage for the signal conditioning, fast analog-to-digital converter (ADC), digital processing algorithms, HV and Preamplifier Power Supply in a compact desktop form factor.
The instrument is suitable for high energy resolution semiconductor detectors, such as HPGe and Silicon detectors, for CZT, but also for scintillation detectors as Nal and LaBr3. It can manage positive and negative signals from resistive feedback or transistor reset preamplifier detectors; additionally accepts signals coming from PMT anodes.
Hexagon can be configured to operate in Pulse Height Analysis (PHA) and in Multichannel Scaling (MCS) acquisition mode; the two modes can even work simultaneously. Multiple PHA spectra can be collected in Multispectral Scaling (MSS) mode with no data loss when switching to a new spectrum. Besides, the Time-stamped List mode permits time and energy events to be saved (on-board or on host PC) for further analysis. Analog input signals as well as internal digital filters outputs can be inspected by the Signal Inspector mode. Exploiting the presence of two input channels, Compton/AntiCompton data acquisition is possible basing on Concidence/Anticoincidence criteria.
I/O Equipment and Additional Features
Hexagon is equipped with a set of I/O panel connectors making it possible to add extra features to the basic MCA. A DB25 I/O connector provides PHA Start/Stop, SCA, MCS, Coincidence/Anticoincidence, Acquisition Start/Stop, ICR, Run Status, Sample Changer and Sample Ready signals. BNC input connectors are reserved for the Transistor Reset Preamp (TRP) inhibit, where the inhibit takes place on an external digital signal and can be extended by a programmable time. Two SATA connectors make possible to synchronize multiple Hexagon units, ensuring easy clock Daisy chain and time stamp alignment with high accuracy.
Panel LED indicators inform the user on the status of the input or output connectors, on the polarity of the power supply channel, or on the correct locking in case of multi-board synchronization. A OLED display provides real-time statistics information like ICR, OCR, real, live and dead time, as well as information on the HVPS channels.
HV and LV Power Supply
Up to two detectors can be supplied by Hexagon. Three ranges of bias voltage and current, software controlled and hardware protected, permit to work with the most used categories of detectors, like PMTs (2 kV / 1 mA), HPGe (5 kV / 30 µA) and Silicon (500 V / 50 µA) detectors. The Positive-Positive, Negative-Negative, or Mixed HVPS polarity can be decided by ordering option, except for the single-input Hexagon version, which is Mixed type only. HV inhibit is supported with both negative and positive polarity. Hexagon integrates also low voltage outputs (±12 V / 100 mA and ±24 V / 50 mA) to supply preamplifiers. External sensor interfacement is possible for Temperature or Nitrogen level readout.
Hexagon is controlled by Quantus, a general-purpose gamma-ray quantitative spectroscopy software. Independently of the detector geometry or sample used, Quantus can analyze any recorded gamma-ray spectrum for radionuclide identification and quantification. Multiple spectra can be analyzed at the same time, and/or acquiring data from several connected detectors is supported. The advanced Graphical User Interface incorporates tools for a wide set of necessary analysis functions: peak searching, peaks continuum subtraction, peak qualification, automatic ROI location, energy calibration with visual interaction, FWHM calibration, efficiency calibration, nuclide identification and activity calculation.
Hexagon keeps the compatibility with MC2Analyzer (MC2A), CAEN multi-board configuration and data acquisition software with basical spectrum analysis (ROI, energy calibration, FWHM, statistics), supporting all CAEN MCAs and digitizers running the DPP-PHA algorithm.
The embedded Linux-based ARM processor makes Hexagon well suited for unattended operations. Taking advantage of the available SDK tool, the user can customize the software (running embedded or on an external PC). The parameters of the processing algorithms can be tuned according to the detector or the application, and custom routines can be developed for automated operations, such as on-board spectrum and list recording, acquisition settings, logging and autonomous data acquisition when unconnected from external hosts.
Hexagon versatility is given also by the supported communication interfaces: point-to-point direct connection through the USB2.0 link and remote network connection by the Ethernet 10/100T port.
The module features a web inteface to perform basic operations without need of any spectroscopy software, but just opening a web browser. It is possible to get the board information (e.g. model type, serial number, firmware version, CPU load averages, real memory occupancy), the list of files saved on the on-board memory, and make operations on each run (order, cut, copy, paste the files, creating and deleting directories, changing the rights, etc.), to manage the network settings and to upgrade the firmware.
Metal with hard rubber supports.
262 W x 66.2 H x 171.6 L mm3 (without connectors)
262 W x 66.2 H x 195 L mm3 (including connectors)Weight
INPUT 0 / 1 (front panel)
– Analog signal input connector; one unit in Hexagon single-input version; BNC type
– Accepts positive or negative signals from PMT anode or both Resistive Feedback and Transistor Reset detector preamplifier; 500 Ω input impedance
– AC or DC coupling selectable by register with 5 µs, 11 µs or 33 µs possible value for the AC time constant; input range is 1 Vpp divided by the selected gain, 4 Vpp with x0.25 or 2 Vpp with x0.5 attenuation activated
HV INH (rear panel)
– High voltage inhibit connector; two units; BNC type
– Inhibit function is duplicated on the rear PREAMP connector; DB9 type.
– Polarity is software selectable (default: Positive polarity)
TRP INH / GATE (front panel)
– Transistor Reset Preamp/Gate Input connector; two units; BNC type; software selectable compatible logic TTL or NIM and function:
– TRP-INH: Transistor Reset Preamplifier Inhibit
– GATE: Input signal acts as gate for coincidence/anticoincidence acquisition mode
DC POWER IN (rear panel)
– 12V DC power jack; mechanically lockable for a safe connection
– Imax: 2.5 A
– AC Adaptor (12 V, 3.75 A) included in the kit
HV 0 / 1 (rear panel)
– Detector High Voltage power supply output connector; two units; SHV type.
– Software selectable triple range of Voltage/Current bias:
– 20 V to 2000 V @ 1 mA
– 20 V to 5000 V @ 30 μA
– 20 V to 500 V @ 50 μA
– Ripple < 5 mVpp.
– HVPS polarity selectable by ordering option (Positive-Positive, Negative-Negative, Mixed); single-input Hexagon version mounts only Mixed HVPS channels.
– Polarity LED identifies positive or negative channel by color
PREAMP 0 / 1
– Preamplifier power supply output connector; two units; DB9 type.
– Two power rails: ±12 V (± 2%) @ 100 mA; ±24 V (± 2%) @ 50 mA
– Ripple < 5 mVpp.
– Included pins for 0 ÷ +10 Vdc level output, for detector temperature (PT100/PT1000 compliant) or Nitrogen level sensor readout, and for HVPS external inhibit input (in OR with HV INH connector; BNC type)
- General Purpose I/Os
GPIO (rear panel)
– Connector for TTL I/Os; one unit; DB25 type (adapter to BNC available on request)
– Inputs (LVTTL, Zin 1 kΩ):
– Trigger Time Stamp Reset: External reset of all the internal counters; software programmable polarity
– Acquisition Start/Stop: External Acquisition Start/Stop signal; minimum pulse width 15 ns; polarity, edge sensitive or level sensitive software programmable
– External Trigger: External Trigger signal; minimum pulse width 15 ns; software programmable polarity
– Acquisition Start/Stop: External Acquisition Start/Stop signal; minimum pulse width 15 ns; software programmable polarity; software programmable as edge sensitive or level sensitive
– MCS Acquire Start/Stop: External Multichannel Scaler Start/Stop signal; minimum pulse width 15 ns; polarity, edge sensitive or level sensitive software programmable
– MCS Channel Advance: External Multichannel Scaler Channel Advance signal; minimum pulse width 15 ns; software programmable polarity
– MCS Sweep Advance: External Multichannel Scaler Sweep Advance signal; minimum pulse width 15 ns; software programmable polarity; the sweep currently in progress can be reset by external pulse
– Sample Ready: Sample Ready signal; minimum pulse width 15 ns; software programmable polarity; acquisition starts on inactive signal, while active signal will delay the start of acquisition
– Outputs (LVTTL, do not require 50 Ω termination):
– ICR: Incoming Count Rate; generates a positive pulse 150 ns wide at each event acquisition.
– SCA: Single Channel Analyzer; output pulse width 150 ns; software programmable polarity; a pulse is generated for each event whose energy stays between the upper and lower level discriminators (ULD, LLD).
– Sample Changer: Sample Changer signal; pulse width 140 ms; software programmable polarity; a pulse is generated for each sample advance command received by the instrument.
- LED Indicators
Front Panel LEDs
– COMM: communication LED; colour green; turns on in case of activity over the USB or the ETHERNET channel.
– STATUS: Status LED; bi-colour red/green:
– Continuous green: the board is ready to start
– Blinking green: the board is in RUN state
– Continuous red: the board is in BUSY state
– HV: HVPS LED; red colour; turns on in case of HV fail.
– INPUT: Trigger LED; colour green; turns on when a trigger is generated on the associated analog input channel.
– TRP-INH/GATE: Transistor Reset Preamplifier inhibit LED; colour green; turns on when the inhibit is active on the associated TRP input channel.
Rear Panel LEDs
– INH: HVPS channel inhibit LED; colour red; turns on when inhibit is active.
– OVC: HVPS channel over-current LED; colour red; turns on if the channel tries to draw more current than the programmed limit.
– ON: HVPS channel enable LED; colour red; turns on when the HVPS channel is active.
– POS: HVPS positive polarity LED; colour green; turns on in case of positive HVPS channel.
– NEG: HVPS negative polarity LED; colour yellow; turns on in case of negative HVPS channel.
– SYNC: Synchronization LED; colour green; turns on when the clock of the board is locked with the clock signal on SYNC IN.
- Acquisition Modes
All settings are saved while the module is in power-off state; last configuration is automatically reloaded at power-on.
– Signal Inspection: the analog input and the outputs of the digital filters can be inspected and plotted to optimize the algorithm parameters for the best spectrum composition.
– PHA: setting the digital pulse processing programmable parameters, energy histograms are built up by the board and can be plotted and saved to file; channels can optionally be: 1024, 2048. 4096, 8192, 16384, 32768. PHA includes advanced modes for spectra management:
– MSS: collects multiple PHA spectra; supports software or external TTL input Spectrum Advance command; not affected by dead-time while switching to a new spectrum.
– Coincidence/Anticoincidence: configurable either for coincidence and anticoincidence between the board analog inputs (IN 0 and IN 1), or for external coincidence (GATE) and external anticoincidence (INH).
– Time-Stamped List: raw energy and time tag data are provided and can be saved to file; 62-bit time tag counter; resolution of 10 ns; roll-over tracking event.
– MCS: Multichannel Scaler mode; counts on fast discriminator, SCA or external inputs; the Start/Stop, the Channel Advance and the Sweep Advance can be on software command or on external signal (GPIO connector).
– Unattended: local storage of lists and spectra on the internal microSD memory without need of external PC control
- Software Selectable Controls (Gain, Offset)
– Setting the combination of coarse and fine gain, the overall gain can be continuously adjusted from x0.8 up to x563.2 with respect to the 1 Vpp input range:
– Coarse Gain: x1, x2, x4, x8, x16, x32, x64, x128, x256
– Fine Gain: from x0.8 up to x2.2 in steps of 0.001
– By selecting the gain attenuation, the input range can be extended to 2 Vpp or 4 Vpp preventing saturation conditions, particularly for preamp signals with large DC offsets or transistor reset preamplifiers with a large output ramp dynamic range:
– Gain Attenuation: x0.25, x0.5
– Configuring the conversion gain defines the number of channels for the acquired spectrum:
– Conversion Gain: 1024, 2048, 4096, 8192, 16384, 32768 channels
DC Offset: The DC offset of the analog input is adjustable in the whole input range
- Software Selectable Controls (Algorithm)
– Input Signal
Pulse Polarity: NEGATIVE or POSITIVE input polarity selection
– Trapezoid Filter: serves for energy calculation; Trapezoid, Trapezoid-Baseline and Peaking signals can be displayed in Signal Inspection mode
– Rise Time: trapezoid rise time corresponds to the shaping time of the traditional analog chain; configurable values between 0.02 μs and 37 μs
– Flat Top: the flat region of the trapezoid, in which the energy is calculated; configurable values between 0.02 μs and 3 μs
– Peak Delay: adjusts the point of the flat top where to calculate the energy value; Peaking (peak position) is a signal which can be displayed in Signal Inspection mode; configurable values between 0% and 100%
– Peak Mean: fixes the number of samples of the flat top where the energy mean is evaluated; configurable values are 1, 4, 16, 64
– Peak Hold-off: starts at the end of the flat top; plays a role in the pile-up rejection; configurable values between 0 µs and 81.84 µs
– Pole/Zero Compensation: exponential decay time fine adjustment to avoid trapezoid overshoot or undershoot for a correct evaluation of the energy value:
– Decay Time: manually and automatically configurable between 0.1 μs and 650 μs
– Baseline Restorer: operates on the trapezoidal filter output to calculate the baseline by averaging a programmable number of points before the start of the trapezoid.
– Fast, Medium, Slow: manual setting of the baseline restorer to a fixed rate
– Fast Discriminator: applies to time tagging and ICR; based on double triangular filter; manual and automatic setting of the threshold; time stamp resolution of 10 ns, 62-bit counter; trigger signal can be displayed in Signal Inspection mode.
– Fast TRG Shaping: configurable values between 0.01 μs and 0.8 μs
– Coupling & TRP: DC/AC coupling selection and Transistor Reset settings
– Coupling: DC coupling option for Charge Sensitive Preamplifiers; AC coupling option for Resistive Feedback and Transistor Reset Preamplifier with three selectable shaping constants: 5 μs, 10 μs and 30 μs (the trapezoid Decay Time must then be set accordingly)
– Reset Length: inhibit time due to the reset discharge (AC coupling); applies to the Transistor Reset Preamplifier
– Pole Zero (%): analog pole zero compensation in case of Resistive Feedback Preamplifier (AC coupling)
– Dwell Time: 1 µs up to 4000 µs with resolution of 1µs
– Channels: 1024, 2048, 4096, 8192, 16384, 32768 selectable channels
16 bitsSAMPLING RATE
SYNC IN (rear panel)
– Input connector for the synchronization of multiple Hexagon boards; one unit; type SATA
– Clock sync, Time tag reset and list marker functions; daisy chainable to multiple boards in combination with SYNC OUT
SYNC OUT (rear panel)
– Output connector for the synchronization of multiple Hexagon boards; one unit; type SATA.
– Daisy chainable to multiple boards in combination with SYNC IN
- Active Buttons
POWER (front panel)
– Power on/off button; blue illuminated when the power is on
RESET (rear panel)
– Holding this button down for 3 seconds causes a global reset of the board (i.e. HVPS channels ramp-down and board reset)
- Monitoring Display
GRAPHIC DISPLAY (front panel)
– Monochrome 1.3ʺ OLED display only for monitoring usage.
– Screen 1: Time acquisition data
– Live Time [hh mm ss] / Real Time [hh mm ss] / Dead Time [%]
– Screen 2: Readout data.
– ICR [Hz], [kHz], [MHz] / OCR [Hz], [kHz], [MHz] / Dead Time [%]
– Screen 3: HVPS data.
– Vmon / Vset [V] / Imon[μA]
BROWSE BUTTONS (front panel)
– Channel select (0<—>1): switches between the two analog input channels (if Screen1 and Screen 2) or the two HPVS channels (if Screen 3).
– Screen select: switches among the different screens.
- Communication Interfaces
USB (rear panel)
Connecting Hexagon to a host PC for the first time, the driver is automatically installed, and Hexagon is directly recognized by the operating system (Windows® and Linux™) also as an external storage unit containing the documentation and the software.
– USB connector; USB2.0 compliant; type mini-A.
– USB cable included in the kit.
10/100 T (rear panel)
– Ethernet female connector; type RJ-45.
– Supports 10 or 100 Mbit/s connection to a PC or ETH hub.
– FTP cable included in the kit.
– Firmware updates are available for free download on CAEN website: www.caen.it.
– Firmware can be upgraded via USB/ETHERNET through the Web Interface.
- On-board CPU and Logging
– 1 ARM Cortex-A8 1 GHz (SDRAM Memory 512 MB DDR3L 800 MHz) running Linux Debian system.
– The embedded CPU is accessible for compiling customized routines and implementing unattended and automated operations by the provided SDK; 2 GB of space available for user installations.
– 32-GB microSD card, non-detachable.
– Logging capability more than 200.000 spectra.
– CAEN MCA Library: free Software Development Kit (SDK) based on a collection of C functions for developers, to be used both on a host PC and on the embedded Linux-based system running on Hexagon CPU; Windows® and Linux™ OS support; stored on Hexagon internal repository; includes practical examples and source files.
– Operable both via the USB and the Ethernet link.
– Network configuration settings, Firmware upgrade and File management functions supported.
– Default IP Address: 172.16.0.2.
– Quantus: High-performance, comprehensive and extensive software package for gamma-ray spectrum analysis and radionuclide identification and quantification; can analyze any recorded gamma-ray spectrum independently of the detector, geometry or sample used; provides all the necessary tools and functionality for performing the detailed analysis of complex gamma-ray spectra and the corresponding radionuclide quantification from the given sample; Windows®, Linux™ and macOS® support.
– MC2 Analyzer: Free software for board configuration, data acquisition in Oscilloscope (Signal Inspection), Time-stamped list or PHA mode; basic mathematical analysis on the acquired spectra (e.g. energy calibration, peak search, background subtraction, peak fitting, etc.); multi-board management; Windows® only supported.
Tested up to 200 kcps.
- Integral Non-Linearity (INL)
0.05% over the 99% of the full-scale range for Coarse Gain < 8; 0.1% for higher gains
- Differential Non-Linearity (DNL)
< ±1% over the 99% of the full-scale range.
Down to 4 keV @ 3 MeV FSR (noise peak at the same height of Compton); measured with 7229P HPGe Canberra detector
- Pile-up Rejection and Live Time Correction
Pulse Pair Resolution: < 0.5 μs typical (depending on the fast discriminator shaping time).
- Dead-Time Correction
Error < 5% on the net area of a static reference source offended by a variable rate source ranging from 1 to 100 Kcps (at fixed Live Time Preset)
Best result is:
– 0.61 keV @ 122 keV
– 1.63 keV @ 1332 keV
measured with Cryo-Pulse 5 Plus Electrically Refrigerated Cryostat HPGe Canberra detector, equipped with iPa Preamplifier
Digital MCAProduct page
|Name||File extension||File size||Revision||Date|
|Hexagon Firmware||CUP||201.95 MB||0.99.2||27/11/2018|
|Name||File extension||File size||Revision||Last update|
|Hexagon Datasheet||4.15 MB||0||14/11/2018|
|Name||File extension||File size||Revision||Last update|
|Hexagon Quick Start Guide||3.93 MB||0||21/09/2018|
|Name||File extension||File size||Revision||Last update|
|Hexagon - Dual Independent 32k Digital MCA with HV & Preamplifier Power Supply||1.31 MB||1||20/10/2017|
Compare with Multi Channel Analyzers.
|WDT5000XMAAA||DT5000M - HEXAGON Dual Dig. MCA - 1 HVPS +5kV/300uA, 1 HVPS -5kV/300uA, 2 LVPS ±12V/100mA, ±24V/50mA|
|WDT5000XNAAA||DT5000N - HEXAGON Dual Dig. MCA - 2 HVPS -5kV/300uA, 2LVPS +/-12V/100mA, +/-24V/50mA|
|WDT5000XPAAA||DT5000P - HEXAGON Dual Dig. MCA - 2 HVPS +5kV/300uA, 2LVPS +/-12V/100mA, +/-24V/50mA|
|WDT5001XMAAA||DT5001M - HEXAGON-one Dig. MCA - 1 HVPS +5kV/300uA, 1 HVPS -5kV/300uA, 1 LVPS ±12V/100mA, ±12V/50mA|