Data Acquisition Electronics Research Articles

A front end ASIC for the readout of the PMT in the KM3NeT detector

In this work, we describe the front end ASIC to readout the Photo-Multiplier-Tube of the KM3NeT detector, in detail. Stringent power budgeting, area constraints and lowering cost motivate us to design a custom front-end ASIC for reading the PMT. The ASIC amplifies the PMT signal and discriminates it against a threshold level and delivers the information via low voltage differential signals (LVDS). These LVDS signals carry highly accurate timing information of the photons . The length of the LVDS signals or Time over Threshold (ToT) gives information on the number of detected photons. A one-time programmable read-only memory (PROM) block provides unique identification to the chip. The chip communicates with the data acquisition electronics via an I2C bus. The data is transmitted to shore via fiber optics, where processing is done. The ASIC was fabricated in 0.35u CMOS process from AustriaMicroSystems (AMS).

Advanced digital self-triggering of radio emission of cosmic rays

Radio detection provides information about the electromagnetic part of an air shower in the atmosphere complementary to that obtained by water-Cherenkov detectors predominantly sensitive to the muonic content of an air shower at ground. For the measurement of ultra-high-energy cosmic rays (UHECR) by the detection of their coherent radio emission, several test setups have been developed and deployed at the Pierre Auger Observatory in Argentina. However, these UHECR radio pulses are significantly polluted by man-made radio frequency interferences (RFI). This requires a special design of antennas, analog, data acquisition (DAQ), and communication electronics, which are under investigation at the Pierre Auger Observatory. In large-scale detector arrays sophisticated self-triggering methods are necessary, to use the limited available communication data rate efficiently. This paper gives an overview of the electronics and self-triggering methods used in the test setups at the Pierre Auger Observatory and describes the experiences gained so far.

Data acquisition electronics for gamma ray emission tomography using width-modulated leading-edge discriminators

We present a new high-performance and low-cost approach for implementing radiation detection acquisition systems. The basic elements used are charge-integrating ADCs and a set of components encapsulated in an HDL (hardware definition language) library which makes it possible to implement several acquisition tasks such as time pickoff and coincidence detection using a new and simple trigger technique that we name WMLET (width-modulated leading-edge timing). As proof of concept, a 32-channel hybrid PET/SPECT acquisition system based on these elements was developed and tested. This demonstrator consists of a master module responsible for the generation and distribution of trigger signals, 2 × 16-channel ADC cards (12-bit resolution) for data digitization and a 32-bit digital I/O PCI card for handling data transmission to a personal computer. System characteristics such as linearity, maximum transmission rates or timing resolution in coincidence mode were evaluated with test and real detector signals. Imaging capabilities of the prototype were also evaluated using different detector configurations. The performance tests showed that this implementation is able to handle data rates in excess of 600k events s−1 when acquiring simultaneously 32 channels (96-byte events). ADC channel linearity is >98.5% in energy quantification. Time resolution in PET mode for the tested configurations ranges from 3.64 ns FWHM to 7.88 ns FWHM when signals from LYSO-based detectors are used. The measured energy resolution matched the expected values for the detectors evaluated and single elements of crystal matrices can be neatly separated in the acquired flood histograms.

Data acquisition electronics and reconstruction software for directional detection of dark matter with MIMAC

Directional detection of galactic dark matter requires 3D reconstruction of low energy nuclear recoils tracks. A dedicated acquisition electronics with auto triggering feature and a real time track reconstruction software have been developed within the framework of the MIMAC project of detector. This auto-triggered acquisition electronic uses embedded processing to reduce data transfer to its useful part only, i.e. decoded coordinates of hit tracks and corresponding energy measurements. An acquisition software with online monitoring and 3D track reconstruction is also presented.

The ClearPEM breast imaging scanner

We present results on the characterization of the ClearPEM breast imaging scanner. ClearPEM is a dual-head positron emission mammography scanner using APD-based detector modules that are capable of measuring the depth-of-interaction (DOI) with a resolution of 2 mm in LYSO:Ce crystals. The full system comprises 192 detector modules with a total of 6144 LYSO:Ce crystals and 384 32-pixel APD arrays read out by ASICs with 192 input channels. The scanner includes front-end and data acquisition electronics and a robotic gantry for detector placement and rotation. The software implements calibration (energy, time and DOI), normalization and image reconstruction algorithms. In this conference, the scanner main technical characteristics, the calibration strategies and the spectrometric performance in clinical environment were presented as well as the images obtained with point sources and with a microDerenzo phantom. The image resolution was found to be of the order of 1.3 mm FWHM (center of field-of-view) and the DOI capability has shown to have a strong impact on the image sharpness. An assessment of the first clinical experience was also presented at the conference.

Explicit modeling of timing characteristics in Compton camera simulation with Geant4

In the present study, a Compton camera, including detailed timing characteristics of the component detectors and related data acquisition (DAQ) electronics, was modeled very accurately with Geant4. The results are very convincing—the inclusion of the timing characteristics in the simulation reduced the imaging sensitivity discrepancy between the simulated and measured data to a negligible level (1–2%) for a 22Na point source; this is a significant accuracy improvement compared with the results obtained previously without modeling the timing characteristics, for which the discrepancies were 30% and 6% for 511 and 1275 keV, respectively. The imaging resolution accuracy was also significantly improved.

GaN-Based High Temperature and Radiation-Hard Electronics for Harsh Environments

We develop novel GaN-based high temperature and radiation-hard electronics to realize data acquisition electronics and transmitters suitable for operations in harsh planetary environments. In this paper, we discuss our research on metal-oxide-semiconductor (MOS) transistors that are targeted for 500 (sup o)C operation and >2 Mrad radiation hardness. For the target device performance, we develop Schottky-free AlGaN/GaN MOS transistors, where a gate electrode is processed in a MOS layout using an Al2O3 gate dielectric layer....

LHCb Silicon Tracker DAQ and ECS Online Systems

The LHCb experiment at CERN is designed to perform precision measurements of b quark decays. The Silicon Tracker plays a crucial role in reconstructing particle trajectories and consists of two silicon micro-strip detectors, the Tracker Turicensis and the Inner Tracker. The radiation environment and the magnetic field represent new challenges for the implementation of the Experiment Control System (ECS) and the data acquisition (DAQ). The DAQ has to deal with ~272 000 analog read-out channels and real-time DAQ at a rate of ~ 1.1 MHz with data processing at the Trigger Electronics and L1 (TELL1) board level. The TELL1 real-time algorithms for clustering thresholds and other computations run on dedicated FPGAs. After data processing the total throughput amounts to about 6.4 GB from an input data rate of ~ 337 GB per second. The ECS is based on the hierarchical finite state machine paradigm and allows distributed control access and multi-platform use. The ECS is able to control and monitor the detector hardware infrastructure (power supplies, DAQ electronics ...) as well as monitor the environmental parameters. It can also take automated actions on warnings or alarms. Finally a completely independent, hardware based safety system ensures the detector safe operation.

The Space Qualified Read-Out Electronics for the e.m. Calorimeter (ECAL) of the AMS-02 Experiment

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a fine grained lead-scintillating fiber sampling calorimeter that allows precise, 3-dimensional imaging of the longitudinal and lateral shower development, providing high electron/hadron discrimination (<formula formulatype="inline"> <tex Notation="TeX">$\sim 10^{6}$</tex></formula>) in combination with the other AMS-02 detectors and a good energy resolution: <formula formulatype="inline"> <tex Notation="TeX">$\Delta E/E\simeq 10\%/\sqrt {E( {\rm GeV})}$</tex></formula>. The ECAL is instrumented with several custom developed electronics subsystems. In addition to the front-end electronics mounted directly on the calorimeter, specific custom boards were developed for supplying high and low voltages and for data acquisition, slow control and trigger. In this article, the ECAL data acquisition, slow control and trigger electronics are described. These boards are composed of two completely independent and separately powered sectors, each capable of carrying out the same functionality. In the case of any fault it is possible to switch from one sector to the other while maintaining full functionality of the ECAL. As for the entire AMS detector, these cards are Space qualified and have been constructed to meet the performance requirements on orbits during 3–5 years of operation. </para>

Depth‐profiling ambient noise in the deep ocean.

Deep Sound is an untethered instrument platform designed to free‐fall from the sea surface to a preassigned depth, at which point a burn wire releases a weight, allowing the system to return to the surface under buoyancy. The descent and ascent rate is 0.6 m/s. A Vitrovex glass sphere houses lithium‐ion batteries and a suite of microprocessor‐controlled electronics for data acquisition, data storage, power management, and system control. Outside the sphere, several hydrophones are arranged in vertical and horizontal configurations, a CTD returns environmental data, and motion sensors monitor pitch, roll, and yaw. Data may be downloaded, and the batteries may be recharged, via throughputs in the sphere. The hydrophones, with a bandwidth of 30 kHz, are rated to a depth exceeding 11 km, and the sphere itself has a depth‐rating of 9 km. The system made three descents in the Philippine Sea in May 2009, to depths of 5100, 5500 and 6000 m; and in November 2009, two descents were made in the Mariana Trench to a depth of 9000 m. On all these deployments, ambient‐noise time‐series were recorded continuously, yielding the power spectrum and vertical coherence of the noise as functions of depth. [Research supported by ONR.]

Development of double-scattering-type Compton camera with double-sided silicon strip detectors and NaI(Tl) scintillation detector

In the present study, a double-scattering-type Compton camera, which incorporates two double-sided silicon strip detectors (DSSDs) as the scatterer detectors and an NaI(Tl) detector as the absorber detector, was constructed as a proof-of-principle system for a compact high-imaging-resolution Compton camera. The energy and timing resolutions of the component detectors were determined accurately for effective Compton imaging. Then, the Compton camera was used to image an 22Na point source at 3.7 cm. The imaging resolutions of the current system were 9.0 and 4.8 mm FWHM for 511 and 1275 keV, respectively, which are fairly good considering the limitations of the detectors and data acquisition (DAQ) electronics employed. Given the characteristics of the component detectors, it is believed that the double-scattering Compton camera can be developed as a very compact system (similar in size to a hand-held radiation survey meter) providing very high imaging resolution.

Portable LTCC gas viscometer for determining Wobbe number

This work presents the continued development of an autonomous portable system for measuring the Wobbe number (calorific content) of gases for the purpose of determining the quality of natural gas. Past research has shown the Wobbe number can be determined if the dynamic viscosity is known. The sensor described here operates on this principle and is essentially a gas viscometer. The sensing components are integrated into single low temperature co-fired ceramic (LTCC) device making the sensor compact and low cost. The sensor was placed within a compact enclosure with data acquisition electronics and was connected to a PC from which a LabVIEW program controls the sensors operation and records the data. It is an evolution of previous work where the sensor concept was proven using a non-integrated system. Preliminary results show the sensor could operate autonomously and was stable when measuring the viscosity of air.

Tactile sensor hardware based on programmable SoC

This reported work focuses on the implementation of data acquisition electronics for a piezoresistive tactile sensor. It commonly involves the use of quite bulky electronics not very suitable to be housed in artificial hands, for instance. A very compact implementation because it is not based on a conventional microcontroller but on a programmable system-on-chip (SoC) is presented. This device implements analogue blocks that are not present in standard microcontrollers, so they do not have to be added as extra integrated circuits on the PCB, and a compact implementation based on a single chip plus a few electronic components is obtained.

Deep Sound: A Free-Falling Sensor Platform for Depth-Profiling Ambient Noise in the Deep Ocean

AbstractAmbient noise in the deep ocean is traditionally monitored using bottom-mounted or surface-suspended hydrophone arrays. An alternative approach has recently been developed in which an autonomous, untethered instrument platform free falls under gravity from the surface to a preassigned depth, where a drop weight is released, allowing the system to return to the surface under buoyancy. Referred to as Deep Sound, the instrument records acoustic, environmental, and system data continuously during the descent and ascent. The central component of Deep Sound is a Vitrovex glass sphere, formed of two hemispheres, which houses data acquisition and storage electronics, along with a microprocessor for system control. A suite of sensors on Deep Sound continuously monitor the ambient noise, temperature, salinity, pressure, and system orientation throughout the round trip from the surface to the bottom. In particular, several hydrophones return ambient noise time series, each with a bandwidth of 30 kHz, from which the noise spectral level, along with the vertical and horizontal coherence, are computed as functions of depth. After system recovery, the raw data are downloaded and the internal lithium ion batteries are recharged via throughputs in the sphere, which eliminates the need to separate the hemispheres between deployments. In May 2009, Deep Sound descended to a depth of 6 km in the Philippine Sea and successfully returned to the surface, bringing with it a unique data set on the broadband ambient noise within and below the deep sound channel. The next deep deployment is planned for November 2009, when Deep Sound will descend almost 11 km, to the bottom of the Challenger Deep at the southern end of the Mariana Trench. If successful, it will return with continuous acoustic and environmental recordings taken from the sea surface to the bottom of the deepest ocean on Earth.

PET Performance Evaluation of an MR-Compatible PET Insert

A magnetic resonance (MR) compatible positron emission tomography (PET) insert has been developed in our laboratory for simultaneous small animal PET/MR imaging. This system is based on lutetium oxyorthosilicate (LSO) scintillator arrays with position-sensitive avalanche photodiode (PSAPD) photodetectors. The PET performance of this insert has been measured. The average reconstructed image spatial resolution was 1.51 mm. The sensitivity at the center of the field of view (CFOV) was 0.35%, which is comparable to the simulation predictions of 0.40%. The average photopeak energy resolution was 25%. The scatter fraction inside the MRI scanner with a line source was 12% (with a mouse-sized phantom and standard 35 mm Bruker 1H RF coil), 7% (with RF coil only) and 5% (without phantom or RF coil) for an energy window of 350-650 keV. The front-end electronics had a dead time of 390 ns, and a trigger extension dead time of 7.32 μs that degraded counting rate performance for injected doses above ~0.75 mCi (28 MBq). The peak noise-equivalent count rate (NECR) of 1.27 kcps was achieved at 290 μCi (10.7 MBq). The system showed good imaging performance inside a 7-T animal MRI system; however improvements in data acquisition electronics and reduction of the coincidence timing window are needed to realize improved NECR performance.

High Speed Multichannel Charge Sensitive Data Acquisition System with Self-Triggered Event Timing.

A number of modern experiments require simultaneous measurement of charges on multiple channels at > MHz event rates with an accuracy of 100-1000 e(-) rms. One widely used data processing scheme relies on application of specific integrated circuits enabling multichannel analog peak detection asserted by an external trigger followed by a serial/sparsified readout. Although this configuration minimizes the back end electronics, its counting rate capability is limited by the speed of the serial readout. Recent advances in analog to digital converters and FPGA devices enable fully parallel high speed multichannel data processing with digital peak detection enhanced by finite impulse response filtering. Not only can accurate charge values be obtained at high event rates, but the timing of the event on each channel can also be determined with high accuracy.We present the concept and first experimental tests of fully parallel 128-channel charge sensitive data processing electronics capable of measuring charges with accuracy of ~1000 e- rms. Our system does not require an external trigger and, in addition to charge values, it provides the event timing with an accuracy of ~1 ns FWHM. One of the possible applications of this system is high resolution position sensitive event counting detectors with microchannel plates combined with cross strip readout. Implementation of fast data acquisition electronics increases the counting rates of those detectors to multi-MHz level, preserving their unique capability of virtually noiseless detection of both position (with accuracy of ~10 μm FWHM) and timing (~1 ns FWHM) of individual particles, including photons, electrons, ions, neutrals, and neutrons.

FinnCRack, a cosmic muon telescope for detector studies

The Finnish Cosmic Rack (FinnCRack) is a position-sensitive telescope measuring the tracks of cosmic particles. The FinnCRack is based on silicon strip detectors and CERN CMS tracker data acquisition electronics. We present the FinnCRack as a reference tracker suitable for the characterization of novel detectors. The FinnCRack is unencumbered by accelerator beam time availability but suffers from a low tracking rate. The resolution of the reference tracks is 18.5 μ m .

The cathode strip chamber data acquisition electronics for CMS

Data Acquisition (DAQ) electronics for Cathode Strip Chambers (CSC) [CMS Collaboration, The Muon Project Technical Design Report, CERN/LHCC 97-32, CMS TDR3, 1997] in the Compact Muon Solenoid (CMS) [CMS Collaboration, The Compact Muon Solenoid Technical Proposal, CERN/LHCC 94-38, 1994] experiment at the Large Hadron Collider (LHC) [The LHC study group, The Large Hadron Collider: Conceptual Design, CERN/AC 1995-05, 1995] is described. The CSC DAQ system [B. Bylsma, et al., in: Proceedings of the Topical Workshop on Electronics for Particle Physics, Prague, Czech Republic, CERN-2007-007, 2007, pp. 195–198] includes on-detector and off-detector electronics, encompassing five different types of custom circuit boards designed to handle the high event rate at the LHC. The on-detector electronics includes Cathode Front End Boards (CFEB) [R. Breedon, et al., Nucl. Instr. and Meth. A 471 (2001) 340], which amplify, shape, store, and digitize chamber cathode signals; Anode Front End Boards (AFEB) [T. Ferguson, et al., Nucl. Instr. and Meth. A 539 (2005) 386], which amplify, shape and discriminate chamber anode signals; and Data Acquisition Motherboards (DAQMB), which controls the on-chamber electronics and the readout of the chamber. The off-detector electronics, located in the underground service cavern, includes Detector Dependent Unit (DDU) boards, which perform real time data error checking, electronics reset requests and data concentration; and Data Concentrator Card (DCC) boards, which further compact the data and send it to the CMS DAQ System [CMS Collaboration, The TriDAS Project Technical Design Report, Volume 2: Data Acquisition and High-level Trigger, CERN/LHCC 2002-26, 2002], and serve as an interface to the CMS Trigger Timing Control (TTC) [TTC system 〈http://ttc.web.cern.ch/TTC/intro.html〉] system. Application Specific Integrated Circuits (ASIC) are utilized for analogous signal processing on front end boards. Field Programmable Gate Arrays (FPGA) are utilized on all boards in the system to provide programmability. The DAQ system has been installed and commissioned, and is ready for LHC data taking.

Development of a new detector and DAQ systems for iBIX

A new photon-counting 2D detector and time-of-flight (TOF) data-acquisition (DAQ) electronics were developed as a system for iBIX diffractometer in J-PARC. The detector system is composed of two ceramic ZnS/ 10B 2O 3 scintillator sheets, 256×2 wavelength-shifting (WLS) fibers, eight 64 ch multi-anode photomultipliers (PMT), a high-speed 512-channel amplifier and discriminator, and a 512-channel encoder module with FPGA for time and position determination. The scintillator sheets have high detection efficiency, 30% and 45% at 1.8 Å for 0.2 and 0.3 mm in thickness, respectively. The WLS fibers (0.5-mm square type) are arranged along X and Y directions with gaps of 0.02 mm; therefore the size of one pixel is 0.52 mm. The PMT have 17% of quantum efficiency for the light from WLS fibers. The detective region (133×133 mm 2) has more than 66% in the front face of the detector. The amplifier and discriminator module has 300 MHz of frequency band, fixed gain (60), and 20–300 mV of discriminator level. The encoder module has many coincidence modes including various pattern-matching methods and a centroid-computation method. The pulse-pair resolution is 4–5 μs. For the DAQ module, we can use both of histogram and event modes for measurement. The recording rate is 5×10 5 events/s for the event mode. Maximum number of the time-channel bins is 4096 for the histogram mode.

Development of neutron detector for engineering materials diffractometer at J-PARC

A prototype neutron detector for engineering materials diffractometer TAKUMI at J-PARC has been developed under international cooperation between Rutherford Appleton Laboratory (RAL) and Japan Atomic Energy Agency (JAEA). The detector head is the same type one as installed in ENGIN-X, ISIS facility, RAL and neutrons are detected based on a nuclear reaction of 6Li(n, α) 3H using ZnS/ 6LiF scintillator. The data acquisition electronics and decoding module were also manufactured. The overall performances of the detector have been tested using various sources. The results showed that the detector met the requirements of TAKUMI and are described in this paper.