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Enhancements in gamma-ray spectral resolution have been realized through hardware development, including low-defect scintillation materials, solid-state detector technology, and low-noise read-out electronics. Enhanced resolution has also been provided by deconvoluting hardware response through the application of spectral unfolding techniques. However, fusing data from multiple independent measurements, both before and after spectral unfolding, to obtain more information than exists from a single measurement represents a largely unexplored path. This work provides a statistical foundation from which data acquired from an arbitrary number of independent gamma-ray spectra can be fused to yield higher resolution than the constituent measurements yield in isolation. Specifically, three data fusion techniques are considered: (i) pulse-height spectrum fusion, (ii) unfolded fluence linear opinion pool, and (iii) unfolded fluence logarithmic opinion pool. We explore the qualitative characteristics of these methods. We then apply them to spectra of thallium-doped sodium iodide [NaI(Tl)] and bismuth germanate (BGO), where all spectra are provided by MCNP simulations. Our results demonstrate improved resolution, thus establishing the methods as an inexpensive alternative to hardware upgrades. Moreover, our results demonstrate that these results have the potential to expand the capability of cutting-edge technology to provide currently unachievable resolution. [ABSTRACT FROM AUTHOR]

The spectroscopic performances of the new integrated ASIC (Application-Specific Integrated Circuit) preamplifiers for highly segmented silicon detectors have been evaluated with an early silicon detector prototype of the TRacking Array for light Charged Ejectiles (TRACE). The ASICS were mounted on a custom-designed PCB (Printed Circuit Board) and the detector plugged on it. Energy resolution tests, performed on the same detector before and after irradiation, yielded a resolution of 21 keV and 33 keV FWHM respectively. The output signals were acquired with an array of commercial 100-MHz 14-bit digitizers. The preamplifier chip is equipped with an innovative Fast-Reset device that has two functions: it reduces dramatically the dead time of the preamplifier in case of saturation (from milliseconds to microseconds) and extends the spectroscopic dynamic range of the preamplifier by more than one order of magnitude. Other key points of the device are the low noise and the wide bandwidth. [ABSTRACT FROM AUTHOR]

We report a new high-precision lifetime measurement of the first excited 5 / 2 + state of 133Cs using NaI(Tl) and LaBr 3 (Ce) detectors. The time difference between the coincident decays of two successive states was measured using fast-timing electronics. The 356-keV (1 / 2 + → 5 / 2 + ) gamma transition was tagged by the successive 81-keV (5 / 2 + → 7 / 2 + ) transition of 133Cs. The half-life of the first excited 5 / 2 + 133Cs state was measured as T 1 / 2 = 6.283 ± 0.004 (stat.) ± 0.011 (syst.) ns. [ABSTRACT FROM AUTHOR]

A 256-channel time-of-flight electronics system has been developed for a facility called “Back-n white neutron source (WNS)” in China Spallation Neutron Source (CSNS). This paper presents the structure and performance of the electronics system and test results at CSNS-WNS. A piece of lithium glass scintillator, coupled with a 256-channel multi-anode photomultiplier tube, is placed at the center of the neutron beam line as the detector. A 256-channel readout electronics system, including one front-end board (FEB), four time-to-digital converter (TDC) cards and one clock distribution module (CDM), measures the arrival time of each signal from the detector. Signals are sent to FEB from the detector through 15-cm cables and discriminated on FEB. FEB drives differential signals over 2-m cables to the TDC cards. Each TDC card has 64 channels, using a field-programmable gate array (FPGA) to measure the arrival time of each signal. The CDM supplies clock signals to the TDC cards to make them work synchronously. The TDC cards and CDM are housed in one peripheral component interconnect (PCI) eXtensions for Instrumentation chassis. The TDC cards achieve a timing precision of 3.5 ns. The electronics system meets the requirement of the experiment and is currently being used in CSNS. [ABSTRACT FROM AUTHOR]

The Circular Electron Positron Collider (CEPC) is a proposing electron–positron collider in China, which aims for generating high center-of-mass energy colliding above 250 GeV. The high-granularity electromagnetic calorimeter (ECAL) is included in a calorimeter system, which is mainly responsible for the measurement of photon. A particle flow algorithm (PFA)-based ECAL solution will utilize about 400k channels/m3. Here, we present the design and development status of readout electronics based on SPIROC2b for the CEPC ECAL with high-granularity scintillants and silicon photomultipliers (SiPMs). The readout electronics consists of front-end electronics (FEE), data interface (DIF) board, and data acquisition (DAQ) board. The front-end board (FEB) carries SiPMs (S12571-010P), scintillants (PSD), and FEB application-specific integrated circuit (ASIC) (SPIROC2b). Two electronics were designed in this paper, one is for ASIC functionality and performance only, and the other is used as a single layer of a further prototype of ECAL. Electronic test and cosmic ray test have been done to electronics. The results indicate that a charge dynamic from 62 fC to 300 pC at S/N = 2 is successfully achieved, and the minimum ionizing particles (MIPs) are separated from the pedestal. [ABSTRACT FROM AUTHOR]

Abstract The motivation of the present paper is to study the performance of EJ 299-33 scintillator in online and off-line analysis in high rate scattering for nuclear reaction experiments performed with heavy ions. An experiment was carried out inside the CHIMERA chamber using 24Mg beams at 71.5 MeV and 81 MeV impinging on 92ZrO 2 target. The plastic scintillator was backed by a photomultiplier tube and the anode pulses were digitized through 100 MHz GET electronics for the purpose of pulse shape discrimination (PSD) studies. Performances of the plastic scintillator have been tested with respect to PSD capabilities and energy spectra analysis under beam irradiations in a high background environment. [ABSTRACT FROM AUTHOR]

We report the characterisation and performance of a low cost muon tracking system consisting of plastic scintillator bars and Silicon Photomultipliers equipped with a customised front-end electronics based on a fast preamplifier network. This system can be used as a detector test bench for astroparticle physics and for educational and outreach purposes. We investigated the device behaviour in self-trigger and coincidence mode, without using LED and pulse generators, showing that with a relatively simple set up a complete characterisation work can be carried out. A high definition oscilloscope, which can easily be found in many university physics or engineering departments, has been used for triggering and data acquisition. Its capabilities have been exploited to discriminate real particles from the background. [ABSTRACT FROM AUTHOR]

The uncertainty in time of particle detection within a scintillator detector, characterised by the coinci- dence time resolution (CTR), is explored with respect to the interaction position within the scintillator crystal itself. Electronic collimation between two scintillator detectors is utilised to determine the CTR with depth of interaction (DOI) for different materials, geometries and wrappings. Significantly, no rela- tionship between the CTR and DOI is observed within experimental error. Confinement of the interaction position is seen to degrade the CTR in long scintillator crystals by 10%. [ABSTRACT FROM AUTHOR]

We describe the optimisation of RadLine®; a small, real time, remotely operated radiation detector, which consists of an inorganic scintillation crystal coupled to a fibre optic cable transporting produced photons to a CCD camera some distance away. RadLine® is tested in a beta and gamma narrow radiation field of 2.4 GBq, from a Caesium-137 (662 KeV) source, at doses rates between 0.125 mSvhr−1 and 10 mSvhr−1. Our results establish that the lower limit of the device corresponds to a dose rate of 0.2 mSvhr−1, constrained by the signal to noise ratio of the instrument. We also demonstrate the process of characterising the RadLine® for utilisation underwater due to its partial electrical inactiveness; and to consider how the instrument might perform in aquatic environments and ultimately in a First Generation Magnox Storage Ponds (FGMSP). The RadLine® brings a marked difference to actual underwater radiation monitoring devices such as; HPGe, CZT and GM detectors, which not only incorporate the whole electronics within and are more bulky, only perform over a short range. The RadLine®’s design offers signification value for intermediate (>100 m) and long range detection. [ABSTRACT FROM AUTHOR]

Abstract: A novel method for direct electronic “fast-timing” lifetime measurements of nuclear excited states via coincidences using an array equipped with equally shaped very fast high-resolution LaBr3(Ce) scintillator detectors is presented. Analogous to the mirror symmetric centroid difference method, the generalized centroid difference method provides two independent “start” and “stop” time spectra obtained by a superposition of the time difference spectra of the N detector fast-timing system. The two fast-timing array time spectra correspond to a forward and reverse gating of a specific cascade. Provided that the energy response and the electronic time pick-off of the detectors are almost equal, a mean prompt response difference between start and stop events is calibrated and used as a single correction for lifetime determination. These combined fast-timing arrays mean time-walk characteristics can be determined for with an accuracy less than 5ps using a 152Eu source. Due to reduction and cancellation of many possible systematic errors, the lifetime determination limit of the method over the total dynamic range is mainly determined by the statistics. The setup of an N=4 detector fast-timing array delivered an absolute time resolving power of 3ps for 10000 events per total fast timing array start and stop time spectrum. The new method is tested over the total dynamic range by the measurements of known picosecond lifetimes in standard sources. [Copyright &y& Elsevier]

Abstract: The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a fine grained lead-scintillating fibres sampling calorimeter that allows for a precise three-dimensional imaging of the longitudinal and lateral shower development. It provides a high ( ) electron/hadron discrimination with the other AMS-02 detectors [1] and good energy resolution. The calorimeter also provides a standalone photon trigger capability to AMS-02. The mechanical assembly was realized to ensure minimum weight, still supporting the intrinsically heavy calorimeter during launch. ECAL light collection system and electronics are designed to measure electromagnetic particles over a wide energy range, from GeV up to TeV. A full-scale flight-like model was tested using electrons and proton beams with energies ranging from 6 to 250GeV. [Copyright &y& Elsevier]

Abstract: The Fibre Active Scintillator Target (FAST) experiment at the Paul Scherrer Institute (PSI) is designed for a high-precision measurement of the lifetime, in the order of a few parts per million. This paper describes the design, construction and performance of the FAST detector and its readout electronics, trigger and data acquisition system. [Copyright &y& Elsevier]

Abstract: The ATLAS Tile Calorimeter is a sampling detector composed by cells made of iron-scintillator tiles. The calorimeter cell signals are digitized in the front-end electronics and transmitted to the Read-Out Drivers (RODs) at the first level trigger rate. The ROD receives triggered data from up to 9856 channels and provides the energy, phase and quality factor of the signals to the second level trigger. The back-end electronics is divided into four partitions containing eight RODs each. Therefore, a total of 32 RODs are used to process and transmit the data of the TileCal detector. In order to emulate the detector signals in the production and commissioning of ROD modules a board called ROD Injector and Multiplexer Board (RIMBO) was designed. In this paper, the RIMBO main functional blocks, PCB design and the different operation modes are described. It is described the crucial role of the board within the TileCal ROD test-bench in order to emulate the front-end electronics during the validation of ROD boards as well as during the evaluation of the ROD signal reconstruction algorithms. Finally, qualification and performance results for the injection operation mode obtained during the Tile Calorimeter ROD production tests are presented. [ABSTRACT FROM AUTHOR]

While the original Compton coincidence technique provided accurate measurements of electron response in scintillators, the data rate was low and measurements took weeks. We present the conceptual design for a high throughput version that is predicted to collect data at 65 cps, reducing measurement times from weeks to hours. In this design, a collimated 1 mCi 137Cs source will illuminate the scintillator sample from a distance of 18 cm and 5 high-purity germanium (HPGe) detectors placed 10 cm from the scintillator will measure the energy of the scattered gamma ray. The source can be placed in either of two positions spaced 15deg apart, allowing relatively uniform scattering angle coverage from 0deg to 146deg, corresponding to electron energies in the scintillator from 0 to 466 keV. The scintillator will be coupled to a hybrid photodetector (HPD), which has extremely linear response, and the HPD's ability to resolve single photoelectrons provides a built-in calibration mechanism. The output of each HPGe detector and the HPD will be digitized with a free-running 12-bit, 200 MHz ADC, providing accurate measurement of the signal amplitudes and the ability to measure the electron response for different temporal components of the scintillator signals. The facility will be located at Lawrence Livermore National Laboratory (LLNL) and is intended to be made available to the community at large. The goals are to facilitate scintillator development and to understand the nature of the light-yield non-proportionality and its effect on the energy resolution. [ABSTRACT FROM PUBLISHER]

This paper investigates the potential of 6LiI(Eu)/photodiode (PD) detector systems for application as neutron counters in radioisotope identification devices (RIID). Those are exposed to mixed neutron-gamma fields. An effective suppression of signals due to gamma interactions with the scintillator or the PD bulk material is of major importance since neutron alarms in RIID are triggered by a few single neutron counts; any gamma signal not rejected may generate a false neutron alarm. Measurements demonstrated that digital signal processing combined with simultaneous pulse height and pulse shape analysis can provide efficient neutron-gamma discrimination. The results were obtained with a compact, basic detector configuration and sampling rates of only 10 MS/s. Such systems can be realized with state-of-the-art miniaturized electronics. [ABSTRACT FROM AUTHOR]

The PIENU experiment is going to be carried out at TRIUMF to measure the ratio of pion decay rates, R = Γ (π+ → e+νe)/Γ(π+ → μ+νμ), to an accuracy of 0.1%. In order to achieve this goal, a muon identification with waveform analysis in a target scintillator is necessary. Due to the short lifetime of pions, muon pulses tend to overlap onto the tail of pion pulses. Thus waveform analysis with a high frequency flash-ADC is essential for the identification and separation of muon pulses. We use the 500-MHz flash-ADC of the COmmon Pipelined Platform for Electronics Readout system, which was developed at KEK, to readout waveforms from the target scintillator. Muon pulse identification capability of this flash-ADC system was investigated by artificial pulses simulating photomultiplier signals. [ABSTRACT FROM AUTHOR]

Abstract: We have measured the performance of silicon photomultipliers (SiPMs) together with the front-end electronics developed for the Compact Muon Solenoid hadron calorimeter. We find a clean separation of the single PE peak above pedestal noise fluctuations, providing a signal to noise of about 8. The SiPMs may be useful in the near term for readout of the outer (HO) scintillators to significantly enhance the sensitivity to minimum ionizing particles for use in the muon trigger. In the longer term, the SiPMs may be useful for upgrading the detector to accommodate a luminosity upgrade. [Copyright &y& Elsevier]

The experimental application of a digital technique for high-resolution estimation of occurrence time of detected events is described. In particular, the method that achieves timing precisions well below the sampling time interval is tested for timing of events from scintillation detectors. The validity of the technique is demonstrated both in terms of achieved performances and of implementation simplicity in an electronic architecture based on a FPGA device. [ABSTRACT FROM AUTHOR]

Readout electronics for the scintillation bar tracking detector (SciBar) in the K2K neutrino oscillation experiment has been developed. SciBar has 14336 scintillator bars in total. The deposited energy and timing of particles from neutrino interactions in the scintillator bars are measured by 64-channel multianode photo-multiplier tubes (MAPMTs). Compact custom-designed electronics to record the MAPMT signals were developed, consisting of front-end circuit boards attached to each MAPMT and back-end electronics modules sitting in a VME crate. The front-end circuit board multiplexes pulse-height information from all 64 anodes and generates a fast triggering signal. Two sets of ASICs (IDEAS VA32HDR11 and TA32CG) are employed for these functions. The bias voltages and relay of control signals are also handled on the board. The back-end electronics module controls the front-end board by providing the control, timing, and low-voltage signals. The board also digitizes the multiplexed signal from the front-end. The electronics achieves low noise of less than 0.3 photoelectrons and and linearity up to 300 (150) photo-electrons for MAPMTs at the gain of 5 × 105 (106). [ABSTRACT FROM AUTHOR]

In this paper, we present a small prototype of Anger camera based on a monolithic array of silicon drift detectors (SDDs) coupled to a single LSO scintillator. The SOD photodetector consists of an array of 19 hexagonal units with on-chip JFET and has about 1 cm2 of total sensitive area. The SOD array was already successfully tested with a CsI(TI) crystal. However, the long scintillation decay time of CsI(TI) requires the use of a long shaping time to reduce the effect of the ballistic deficit. This requirement does not allow to fully exploit the low electronics noise of the SOD, which, on the contrary, reaches its minimum noise at short shaping times. Moreover, the use of a faster scintiliator would improve the overall counting rate capability of the Anger Camera. On the other side, the LSO scintillator is characterized by a lower scintillation conversion efficiency with respect to CsI(TI) and by a natural background. In this work the performances which could be expected from a LSOSSDD Anger Camera are first evaluated. Then, the results achieved in the experimental characterization of a prototype of this detector are presented. A position resolution better than 1 mm FWHM using a 57Co source (122 keV) has been measured. [ABSTRACT FROM AUTHOR]

A compact, low noise, and low cost readout system based on commercially available application-specific integrated circuits (ASICs) is under investigation. These front-end circuits have been used to readout a prototype detector module comprising Lutetium Oxyorthosificate (LSO) scintillation crystals coupled to avalanche photodiode (APD) arrays. A major goal for this work is to build a dedicated high performance breast imaging PET system. Characteristics of signal response, noise, pedestals and gain of the chip have been evaluated. The channels have a linear response to within 2% across a ± 50 fC dynamic range. The circuits allow hardware adjustment of bias levels to allow gain uniformity of less than 5% for all channels within a chip and the gain performance is very stable over all channels. Initial tests of the chip when connected to a prototype APD array also showed good performance. 13% energy resolution was obtained with direct 5.9 keV X-ray interactions in an individual APD pixel. Initial performance evaluation indicates that the ASIC may serve as a foundation for front-end readout electronics for the proposed PET system. [ABSTRACT FROM AUTHOR]

Flash Analog-to-Digital Convertor (FADC) is frequently used in Nuclear and Particle Physics experiments, often as the major component in big multi-channel systems. The large data volume makes the optimization of operating parameters necessary. This article reports a study of a method to extend the dynamic range of an 8-bit FADC from the nominal 28 value. By comparing the integrated pulse area with that of a reference profile, good energy reconstruction and event identification can be achieved on saturated events from CsI(Tl) crystal scintillators. The effective dynamic range can be extended by at least four more bits. The algorithm is generic and is expected to be applicable to other detector systems with FADC readout. [Copyright &y& Elsevier]

This paper presents a simulation/experimental technique used in the design of optimum performance read-out electronics for a new cosmic ray telescope composed of scintillator bars. This new detector, called SciBar Cosmic Ray Telescope (SciCRT), is installed on top of Sierra Negra volcano in Mexico, operating at an atmospheric depth of 575 g cm−2. The severe atmospheric conditions and high background rate of the place currently limit the performance of the detector, therefore the requirements of our design are low power consumption and high throughput rate. The simulation developed considers the interaction of high energy cosmic ray muons with the scintillator bar, generation and propagation of photons inside a wavelength shifting fiber (WLS) fiber and the detection by a multi-anode photomultiplier (MAPMT). To produce realistic signals coming from the interaction of particles, our method relies on the extraction of different parameters throughout experiment to include them in the simulation. In addition, the paper presents a muon cosmic ray experiment designed to validate the results of the simulation and test the performance of the new electronics. [ABSTRACT FROM AUTHOR]

Measurements have been performed with scintillation crystals of LaBr 3 :Ce coupled to an array of Silicon Photomultipliers (SiPMs) in a 3 T magnetic field. The SiPMs were read out by digital data acquisition systems, including the GET electronics system. Inside of the B-field, energy resolution values of 3.82% FWHM at 661.7 keV are reported for a 1.5$\protect \relax \special {t4ht=′}\protect \relax \special {t4ht=′}$ cubic LaBr 3 :Ce crystal coupled to a 6 × 6 array of 6 × 6 mm2 SiPMs. No measurable degradation in energy resolution due to the presence of the strong magnetic field was observed. [ABSTRACT FROM AUTHOR]

Jiangmen Underground Neutrino Observatory (JUNO) is a next generation liquid scintillator neutrino experiment under construction phase in South China. Thanks to the anti-neutrinos produced by the nearby nuclear power plants, JUNO will be able to study the neutrino mass hierarchy, one of the open key questions in neutrino physics. One key ingredient for a successful measurement is to use high speed, high resolution sampling electronics located very close to the detector signal. Linearity in the response of the electronics is another important ingredient for the success of the experiment. During the initial design phase of the electronics, a custom design with the Front-End and Read-Out electronics located very close to the detector analog signal has been developed and successfully tested. The present paper describes the electronics structure and the first tests performed on the prototypes. The electronics prototypes have been tested and they show good linearity response, with a maximum deviation of 1.3% over the full dynamic range (1-1000 p.e.), fulfilling the JUNO experiment requirements. [ABSTRACT FROM AUTHOR]

Abstract: A PET imaging system demonstrator based on LYSO crystal arrays coupled to SiPM matrices is under construction at the University and INFN of Pisa. Two SiPM matrices, composed of 8×8 SiPM pixels, and 1,5mm pitch, have been coupled one to one to a LYSO crystals array and read out by a custom electronics system. front-end ASICs were used to read 8 channels of each matrix. Data from each front-end were multiplexed and sent to a DAQ board for the digital conversion; a motherboard collects the data and communicates with a host computer through a USB port for the storage and off-line data processing. In this paper we show the first preliminary tomographic image of a point-like radioactive source acquired with part of the two detection heads in time coincidence. [Copyright &y& Elsevier]

The electromagnetic calorimeter of the Belle II detector and its performance in the first SuperKEKB run during 2018 are described. It is a high-granularity calorimeter based on 8736 CsI(Tl) scintillating crystals. The scintillation light is detected by PIN photodiodes. Each calorimeter electronics readout channel includes a charge sensitive preamplifier attached to the crystal and a 2 MHz flash ADC followed by a wave form analysis (WFA) realized in FPGA which provides both amplitude and time reconstruction. Usage of the WFA reduces a contribution of the pile-up noise. High time resolution provides the beam background suppression. In the Belle II experiment the calorimeter is used for particle energy measurement, particle identification as well as for the collider luminosity measurement, it also contributes to the first-level trigger. [ABSTRACT FROM AUTHOR]

A detector system is designed for a high-energy phase-contrast computed tomography (CT) experimental device with an X-ray tube voltage of 80 kV. The spot size of the X-ray tube is 0.4 mm*0.7 mm. The Gd2O2S scintillator detector is adopted in our design, which is characterized by a high detection efficiency and high light yield. This system contains 2304 channels and the corresponding high-density read-out electronics. Considering the influence of the large spot size of the X-ray tube source, a detector pixel size of 0.75 mm*1 mm is adopted to obtain sufficient spatial resolution. Because the light intensity fluctuation caused by the phase shift is very weak, a 20bit ADC is used to achieve sufficient efficient resolution (ER). The electronics test shows that the SNR can reach 72. Compared to a commercial detector board, the detector system has better resolution for the sample used in the phase-contrast imaging experiment. [ABSTRACT FROM AUTHOR]

The PAMELA satellite-borne experiment, scheduled to be launched in 2004, is designed to provide a better understanding of the antimatter component of the cosmic rays. Its ToF scintillator system will provide the primary experimental trigger and time-of-flight particle identification. The time resolution requested is σt < 120 ps. To fulfill the detector requirements the digitization electronics should have a time resolution &les;50 ps and provide a wide dynamic range for charge measurements. The peculiarity of the developed electronics arises from the need to obtain such a time resolution operating in a satellite environment, which implies low-power consumption, radiation hardness, redundancy and high reliability. [Copyright &y& Elsevier]

The LHCb preshower is a scintillator plane preceded by a lead sheet of 2.5 radiation lengths. Its main task is to validate the electromagnetic nature of the showers for the Level 0 trigger. The readout system, working at the LHC frequency, has a large dynamics, high accuracy and allows successive triggers. It includes 64 anode photomultiplier tubes, an analogue very front end board and a digital front end board. The full readout system will be described in the following. [Copyright &y& Elsevier]

The Pierre Auger Observatory is the largest installation worldwide for the investigation of ultra-high energy cosmic rays. Air showers are detected using a hybrid technique with 27 fluorescence telescopes and 1660 water-Cherenkov detectors (WCD) distributed over about 3000 km 2 . The Auger Collaboration has decided to upgrade the electronics of the WCD and complement the surface detector with scintillators (SSD). The objective is to improve the separation between the muonic and the electron/photon shower component for better mass composition determination during an extended operation period of 8–10 years. The surface detector electronics records data locally and generates time stamps based on the GPS timing. The performance of the detectors is significantly improved with a higher sampling rate, an increased dynamic range, new generation of GPS receivers, and FPGA integrated CPU power. The number of analog channels will be increased to integrate the new SSD, but the power consumption needs to stay below 10 W to be able to use the existing photovoltaic system. In this paper, the concept of the additional SSD is presented with a focus on the design and performance of the new surface detector electronics. [ABSTRACT FROM AUTHOR]