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In this study, we introduce the concept and construction of an innovative Digital Miniature Cathode Ray Magnetometer designed for the precise detection of magnetic fields. This device addresses several limitations inherent to magnetic probes such as D.C. offset, nonlinearity, temperature drift, sensor aging, and the need for frequent recalibration, while capable of operating in a wide range of magnetic fields. The core principle of this device involves the utilization of a charged particle beam as the sensitivity medium. The system leverages the interaction of an electron beam with a scintillator material, which then emits visible light that is captured by an imager. The emitted scintillation light is captured by a CMOS sensor. This sensor not only records the scintillation light but also accurately determines the position of the electron beam, providing invaluable spatial information crucial for magnetic field mapping. The key innovation lies in the combination of electron beam projection, CMOS imager scintillation-based detection, and digital image signal processing. By employing this synergy, the magnetometer achieves remarkable accuracy, sensitivity and dynamic range. The precise position registration enabled by the CMOS sensor further enhances the device's utility in capturing complex magnetic field patterns, allowing for 2D field mapping. In this work, the optimization of the probe's performance is tailored for applications related to the characterization of insertion devices in light sources, including undulators. [ABSTRACT FROM AUTHOR]

The FAZIA apparatus is a multi-detector array designed to identify a wide range of charge and mass of reaction products in heavy-ion collisions in the Fermi energy domain. The basic module of FAZIA is the block, consisting of 16 three-layer telescopes. The first two layers are highly homogeneously doped Si detectors with thicknesses of 300 μ m and 500 μ m , respectively, and the third layer is a 10 cm thick CsI(Tl) scintillator read out by a photodiode. The detector signals are extracted in real time based on the digital signal processing implemented on the FPGAs. The recent experiments demonstrated that the charge could be discriminated up to more than Z = 54 using the Δ E-E technique and the pulse shape analysis. In addition, the isotopic discrimination has been achieved up to Z ∼ 25 with the Δ E-E technique and up to Z ∼ 20 with the pulse shape analysis in the silicon layer. Recently, there have been activities for the FAZIA detector upgrade to use thicker and thinner silicon layers for enlarging the kinematic coverage. In addition, R&D is in progress to make the front-end electronics board more compact and versatile. This paper is dedicated to the description of the current status of the FAZIA detector and some highlights of the R&D activities for the upgrade. [ABSTRACT FROM AUTHOR]

Precise measurement under high counting rates has been a major challenge for γ -ray spectroscopy, where signals generally pile up with each other and their characteristic values are deeply coupled. An off-line pile-up pulse recovery algorithm based on template matching is developed for LaBr 3 scintillation detectors and has been applied to data from China Spallation Neutron Source (CSNS) Back-n white neutron beamline. As an improvement to the traditional Template Matching methods, the predetermined template shape is associated with pulse amplitudes, which is found crucial to achieve the best fitting results. Moreover, a universal strategy of setting the initial values of fitting allows to resolve signals that are separated in time by less than the characteristic rise time. Processing of simulated pulses demonstrates that the lower limit of interval to distinguish successive events is 10 ns, which is a significant improvement to the previous works. The algorithm performs well under a counting rate of 6 × 1 0 7 s−1, and is still effective up to 1 0 8 s−1. Analysis of experimental data indicates that this algorithm recovers over 98% count yield under a counting rates of no more than 4 × 1 0 6 s−1 in this work, providing a more reliable approach to deduce neutron-induced reaction cross sections. [ABSTRACT FROM AUTHOR]

NaI(Tl) scintillators can detect thermal neutrons with surprising efficiency, even in the presence of ambient gamma radiation. This is due to a peculiarity of the 128I level scheme. Deexcitation cascades following neutron captures in 127I, a main constituent of NaI with quite large neutron capture cross section, unexpectedly often involve the 167.4 keV state of 128I with 175 ns half-life, which feeds another isomeric level at 137.9 keV having a half-life of 845 ns. The 29.5 keV transition between both levels, as well as the subsequent deexcitation sequence to ground state comprising 137.9 keV sum energy, are almost certainly absorbed in the crystal. Signals including three scintillation pulses within few microseconds, the first one caused by a prompt part of the cascade, the second and third one disclosing 30 and 138 keV energy depositions and characteristic delays, are clearly related to such neutron captures. Double-pulse sequences comprising only the primary pulse and a delayed 138 keV signal are also distinctive but more prone to load-dependent background by random pulse pileups. This article demonstrates neutron detection with a Ø2” $\times2$ ” NaI(Tl) scintillation detector by finding and analyzing such double- and triple-pulse sequences in digitized detector signals. It quantifies effect and background rates as a function of the detector load ranging up to 30 kcps. Complementary measurements with a 6Li codoped Ø2” $\times2$ ” NaI(Tl) (NaIL) scintillator allow relating the neutron detection yield by delayed-coincidence counting to the 6Li capture rate in the same crystal and thus to evaluate prospects and limits of this technique. [ABSTRACT FROM AUTHOR]

Upgrades to the Spallation Neutron Source at Oak Ridge National Laboratory will provide a second target station and an increased neutron flux, which will offer a more powerful tool for neutron reflectometry. To fully utilize the higher neutron flux, a high-speed, neutron-imaging device (an imaging plane) specifically for reflectometry is required. The neutron imaging plane requires a detection efficiency of 60% for 2 Å neutrons for event rates exceeding 2 Mcps/cm2 with less than 10% dead time. A novel organic glass scintillator material loaded with a boron compound demonstrated good neutron sensitivity. Simulations show that the detection efficiency for thermal neutrons can reach 60% with a 500- $\mu \text{m}$ thickness, if the glass is loaded with 99% enriched $^{10}\text{B}$ compound at 10% wt. A lower concentration of 95% enrichment at 5% wt loading can provide 60% efficiency with a thickness slightly above 1 mm. The decay time of the scintillator is less than 100 ns, providing a fast response for high rate counting. The instrument design is based on detecting the neutron with a fast scintillation material and integrating silicon photomultipliers (SiPMs) with high-speed digital electronics. Traditional pulse sampling using a high-speed analog to digital converter (ADC) to conduct pulse shape discrimination is not viable for imaging, and a new technique has been formulated for this material using a time over threshold (TOT) method to isolate neutrons from gamma-ray interactions. The gamma-neutron peak separation is greater than two sigma, and with a thin scintillator, the gamma-ray rejection per detected neutron should meet the design specification of $10^{-6}$. Using the TOT method, the digital information to be processed by an interfacing ADC is reduced allowing for readout per SiPM, providing a position resolution close to 1 mm. [ABSTRACT FROM AUTHOR]

The concept of an active dosimetry system for pulsed radiation dose rate measurements is presented. Real-time distinction of pulsed and non-pulsed radiation contributions is based on the time structure of a single interaction. A fast tissue equivalent plastic scintillator is exploited to minimize the pile-up effect influence on absorbed energy measurements. Being connected to a fully digital signal processing board, the detector creates an active dosimetry system with adjustable parameters. With this system, absorbed dose rate measurements were carried out in a photon field with a time structure mimicking a radiotherapeutic beam, but also in the presence of a constant radiation field. Measurements show a linear dependence of a pulsed radiation contribution on the accelerator current in the investigated range of the total dose rate up to 8 μGy h−1. While increasing the accelerator current by 1 μA, the pulsed radiation dose rate grows by (26.2 ± 0.9) nGy h−1 when considering pile-up events. [ABSTRACT FROM AUTHOR]

• A technique for the clustering of electrical signals is proposed. • The clustering algorithm has been customized for the electrical pulses from high-energy particle detectors. • Clustering has been applied on the electrical signal coming from scintillator under radiation. • The ability to identify neutrons and gamma patterns has been verified. In several nuclear applications, scintillators, coupled with a photomultiplier and pulse amplifier, are used in order to detect high energy particles, i.e. neutrons and gamma rays. The different particles incident on the scintillator produce electrical pulses having different shape; moreover, the amplitude of these signals is related to the particles energy. The electrical pulses of the scintillator chain are acquired by digital systems that, generally, perform a triggered acquisition consisting of a stream of pulse windows. The aim of this study is the development of a simplified clustering algorithm able to produce reference patterns in compliance with the pattern recognition algorithm based on the matched filter technique, starting from a stream of pulses generated by particles having different energy and type. This paper contains a general description of the clustering algorithm and of the main customizations performed for the scintillator signals. In order to test in real case the efficiency, the algorithm has been applied on the data acquired during a radiation test performed at Frascati Neutron Generator for Stilbene scintillator. The results show that this algorithm works properly, deriving the centroids of the clusters representing the neutron and gamma shapes, together with their occurrences in the analysed data stream. [ABSTRACT FROM AUTHOR]

Abstract Pulse digitization at high rates has paved the way for the use of complex, non-standard algorithms, beyond the conventional constant fraction discriminator (CFD) option to obtain the time-stamps of gamma photons arriving to nuclear detectors. Detector pulses can be shaped with digital filters in digital signal processing (DSP) hardware or software, and timestamps can be derived by interpolating or extrapolating the acquired samples. Digitized pulses can be stored in a computer for off-line analysis allowing for many different algorithm variations to be tried on the same data. One difficulty is that the number of filters and parameters to be tuned in order to optimize the timing performance may become too large to be done by hand. For this, in this work we use a genetic algorithm to tune in-silico digital filters, digital time pickup algorithms and their associated parameters. The data set consisted of 500,000 pulses obtained from the last dynode of two ultrafast photomultiplier tubes (model R9779 by Hamamatsu) coupled to monolithic fast inorganic LaBr 3 (Ce) scintillators, in a truncated cone geometry 1.5 × 1 × 1.5". With finely tuned conventional (CFD+TAC) timing electronics, a CRT of 155 ps (FWHM) for a 60Co source has been measured by our group, within the state of the art for detectors of this size. Our alternate digital, in-silico implementation of CFD+TAC, fine-tuned with the same parameters obtained during manual adjustment of the conventional DAQ and applied to pulses digitized at 5 GS/s and 14 bits of vertical resolution, reproduces the performance of the conventional DAQ. On the other hand, a genetic algorithm (GA) is employed to optimize digital recursive filters with up to 8 parameters, and different time-pickup strategies (upper level thresholding, CFD, time extrapolation). The same 500,000 pulses are employed for which the GA finds several families of filters outperforming the manually tuned algorithm by more than 10%. [ABSTRACT FROM AUTHOR]

Abstract An analysis of various n/ γ separation algorithms for a digital neutron spectrometer based on a stilbene crystal is performed. The same set of digital signals is used to test the following n/ γ separation algorithms: the algorithm based on the correlation analysis; the algorithms based on the direct comparison of the pulse fast component and the pulse tail; SDCC (Simplified Digital Charge Collection) algorithm; PGA (Pulse Gradient Analysis) and FGA (Frequency Gradient Analysis) algorithms. It is shown that the algorithm based on the correlation analysis makes it possible to carry out the most effective n/ γ separation for the entire pulse areas range. The shape of the distributions of the separation parameter for electrons and protons is analyzed. The correctness of these distributions approximation by the Gaussian curve is justified. An algorithm for the selection of the recoil protons resulting from the neutron interaction with the scintillator is proposed. It is based on the dynamic change of the separation parameter threshold depending on the pulse area. The distributions of the separation parameter for electrons and recoil protons strongly overlap for small pulse areas. In this case, the threshold for the separation parameter is chosen on the basis of the fixed probability of the event false identification. In our work, for example, the contribution of false events was fixed at 1%. With the increase of the pulse area, the distributions for electrons and protons begin to separate well. In this case it is convenient to set the threshold on the separation parameter at the point of their intersection. The use of this algorithm makes it possible to control the fraction of the falsely identified events for the entire range of the pulse areas. This is especially important for low-energy recoil protons, for which the probability of false event identification reaches its maximum. This algorithm was applied to the measurements performed by the time-of-flight method with a 252 Cf source. The suppression degree of the prompt gamma-ray peak was 1100 at the neutron detection threshold of 275 keV. The contribution of the falsely identified events for the different parts of the time-of-flight spectrum using the proposed event selection algorithm was studied. The largest contribution to the false pulses was found for the neutron distribution edges — for the neutrons with the energies above 8 MeV and below 0.5 MeV, and it did not exceed 0.23% in the entire range of the pulse areas. [ABSTRACT FROM AUTHOR]

Nowadays, it is possible to accelerate bunches of particles in the interaction of ultrahigh intensity (UHI) laser pulses with matter. Electrons, protons, ions, and high-energy photon beams can be produced in experiments and reach kinetic energies close to hundreds of megaelectronvolts for protons and gigaelectronvolts for electrons and for the associated Bremsstrahlung photons. At these energies, these beams can induce a large variety of nuclear reactions, which can be detected and studied using $\gamma $ -ray spectroscopy techniques. At standard accelerator facilities, scintillator detectors are commonly used to perform prompt $\gamma $ -ray spectrometry studies. However, during laser–matter interactions, high fluxes of X-rays (mostly soft) are generated, which lead to instantaneous huge energy deposits (~1 $\mu \text{J}$) in these scintillators. Depending on the laser characteristics (energy and pulse duration), the detector recovery time after these X-ray flashes can reach several milliseconds, which makes any prompt or “in beam” measurement impossible. The origin of this long-duration signal is investigated in the case of a LaBr3 crystal coupled to different photodetectors. While it was impossible using standard photomultiplier tubes to detect $\gamma $ -ray emissions before a few milliseconds after a laser shot, we could, using a hybrid photodiode, resolve single $\gamma $ -ray emission a few tens of microseconds after the laser shot. Furthermore, we have also shown that the LaBr3 scintillator presents an unexpected long-lived light emission (afterglow). Directions are suggested for future studies in order to minimize the effects of this afterglow emission. [ABSTRACT FROM AUTHOR]

In this article we present a method of characterizing scintillating materials by digitization of each individual scintillation pulse followed by digital signal processing. With this technique it is possible to measure the pulse shape and the energy of an absorbed gamma photon on an event-by-event basis. In contrast to time-correlated single photon counting technique, the digital approach provides a faster measurement, an active noise suppression, and enables characterization of scintillation pulses simultaneously in two domains: time and energy. We applied this method to study the pulse shape change of a CsI(Tl) scintillator with energy of gamma excitation. We confirmed previously published results and revealed new details of the phenomenon. [ABSTRACT FROM AUTHOR]

We report on the dedicated implementation of the blocking technique for a LaBr 3 (Ce) detector as well as associated electronics and data acquisition system for border protection applications. The detector is meant to perform delayed γ -ray spectroscopy of fission fragments produced via photofission induced by a high intensity pulsed photon beam. The gating technique avoids saturation of the detection chain during irradiation. The resulting setup allows us to successfully perform delayed γ -ray spectroscopy starting only 30 ns after the gating operation. The measured energy resolution ranges from 5% to 6.5% at 662 keV depending on the γ -ray detection time after the gating operation. [ABSTRACT FROM AUTHOR]

Deuterated ( 2 H -based) organic scintillators, unlike conventional 1 H -based scintillators can generate pulse-shape gated neutron energy spectra 1 to 30 MeV without need for time-of-flight (ToF). They are especially appropriate for measurements at high-intensity, low-energy accelerators where a pulsed beam is not available. Even when the latter is available, the loss in effective beam intensity combined with the need for suitable long-path ToF measurements can be very inefficient. In contrast, as we demonstrate, arrays of d- benzene scintillators (NE230, BC537, EJ315) and recently xylene-d10 (EJ301D) together with related digital signal processing (DSP) can provide highly efficient neutron energy measurements w/o n-ToF. We also report the recent synthesis and initial testing of crystalline d-stilbene as a neutron detector. [ABSTRACT FROM AUTHOR]

Scintillation detectors offer a single-step detection method for fast neutrons and necessitate real-time acquisition, whereas this is redundant in two-stage thermal detection systems using helium-3 and lithium-6, where the fast neutrons need to be thermalized prior to detection. The relative affordability of scintillation detectors and the associated fast digital acquisition systems have enabled entirely new measurement setups that can consist of sizeable detector arrays. These detectors in most cases rely on photomultiplier tubes, which have significant tolerances and result in variations in detector response functions. The detector tolerances and other environmental instabilities must be accounted for in measurements that depend on matched detector performance. This paper presents recent advances made to a high-speed FPGA-based digitizer. The technology described offers a complete solution for fast-neutron scintillation detectors by integrating multichannel high-speed data acquisition technology with dedicated detector high-voltage supplies. This configuration has significant advantages for large detector arrays that require uniform detector responses. We report on bespoke control software and firmware techniques that exploit real-time functionality to reduce setup and acquisition time, increase repeatability, and reduce statistical uncertainties. [ABSTRACT FROM AUTHOR]

X-ray computed tomography (CT) is non destructive visualization inside the human body. Recently, X-ray photon-counting CT (PC-CT) has drawn attention for reducing the high doses used for patients and acquiring spectral information to identify materials. To enable photon-counting imaging with a wide region (∼ 60 mm long) of a small animal, we developed a photon-counting system using a 64-channel multi-pixel photon counter (MPPC) array with a fast temporal response (a few nanoseconds) and a very large signal gain (∼ 1 0 6 ), combined with a 64-channel yttrium–gadolinium–aluminum–gallium garnet scintillator array. In particular, to realize ultra-fast analog and digital signal processing (> 10 MHz/channel), we developed a 64-channel large-scale integrated circuit (LSI) named MPPC-CT64. We had previously developed a 16-channel PC-CT system with a 16-channel LSI (MPPC-CT16). Although the MPPC-CT16 realized photon-counting imaging for a ∼ 16-mm-long phantom, there were some energy uncertainties in the LSI, which degraded the obtained CT image quality. The MPPC-CT64 implements a function for correcting the threshold energies and also increases the number of energy thresholds from four to six, which provides more precise measurements of CT values dependent on X-ray energy. In this paper, we briefly present the electric architecture and performance evaluation of the LSI combined with MPPCs. [ABSTRACT FROM AUTHOR]

The in-beam positron emission tomography (ibPET) is dedicated to radiotherapy imaging of the heavy-ion medical machine (HIMM), which requires precise online measurement, as well as real-time signal processing capability of the electronics. In this paper, we present the implementation of real-time digital signal processing in the data acquisition unit (DAQU) for an ibPET system based on the photomultiplier tube (PMT) readout of lutetium-yttrium oxyorthosilicate (LYSO) scintillator crystals. We have designed 10-channel customized signal processing circuit on a high-performance FPGA, which supports 3 working modes (single event processing mode, self-calibration mode and raw ADC data mode), position calculation, crystal locating, event sorting, and etc. Moreover, the implementation of real-time corrections is capable of dealing with photon peak correction to 511 keV and crystal ID-based time correction. The implemented real-time ibPET system can achieve 46% data compression and beyond 1,000,000 events/sec/channel signal processing capabilities. A series of initial tests is conducted, and the results indicate that this design meets the application requirement on online processing. [ABSTRACT FROM AUTHOR]

Basic concepts and the development of a high counting rate digital spectrometry system based on efficient ADCs and latest available FPGA are presented with the aim of using such a system, coupled to fast scintillators, in plasma experiments. The prototype system is a 1 channel 12-bit 1 GSPS digitizer with 2~\mathrm V\mathrm {pp} input voltage. Preliminary results tested with different radioactive sources are shown for low (0.03 Mcps) and high (2.2 Mcps) counting rates. A comparison of energy spectra and energy resolution with what obtained by a commercial device is also shown. [ABSTRACT FROM PUBLISHER]

Pulse shape discrimination applied to certain fast scintillators is usually performed offline. In sufficiently high-event rate environments data transfer and storage become problematic, which suggests a different analysis approach. In response, we have implemented a general purpose pulse shape analysis algorithm in the XIA Pixie-500 and Pixie-500 Express digital spectrometers. In this implementation waveforms are processed in real time, reducing the pulse characteristics to a few pulse shape analysis parameters and eliminating time-consuming waveform transfer and storage. We discuss implementation of these features, their advantages, necessary trade-offs and performance. Measurements from bench top and experimental setups using fast scintillators and XIA processors are presented. [ABSTRACT FROM AUTHOR]

Recently invented plastic scintillator EJ-299-33 enables pulse-shape discrimination (PSD) and thus measurement of neutron and photon spectra in mixed fields. In this work we compare the PSD properties of EJ-299-33 plastic and the well-known NE-213 liquid scintillator in monoenergetic neutron fields generated by the Van de Graaff accelerator using the 3 H(d, n) 4 He reaction. Pulses from the scintillators are processed by a newly developed digital measuring system employing the fast digitizer card. This card contains two AD converters connected to the measuring computer via 10 Gbps optical ethernet. The converters operate with a resolution of 12 bits and have two differential inputs with a sampling frequency 1 GHz. The resulting digital channels with different gains are merged into one composite channel with a higher digital resolution in a wide dynamic range of energies. Neutron signals are fully discriminated from gamma signals. Results are presented. [ABSTRACT FROM AUTHOR]

This paper presents structure, design and implementation of a novel technique for determining the optimal shaping, in time-domain, for spectrometers by means of a Genetic Algorithm (GA) specifically designed for this purpose. The proposed algorithm is able to adjust automatically the coefficients for shaping an input signal. Results of this experiment have been compared to a previous simulated annealing algorithm. Finally, its performance and capabilities were tested using simulation data and a real particle detector, as a scintillator. [ABSTRACT FROM AUTHOR]

We present a digital signal processing system based on a photon counting approach which we developed for a thermal neutron detector consisting of ZnS(Ag): 6 LiF scintillating layers read out with WLS fibers and SiPMs. Three digital filters have been evaluated: a moving sum, a moving sum after differentiation and a digital CR-RC 4 filter. The performances of the detector with these filters are presented. A full analog signal processing using a CR-RC 4 filter has been emulated digitally. The detector performance obtained with this analog approach is compared with the one obtained with the best performing digital approach. [ABSTRACT FROM AUTHOR]

Gamma ray spectrometry measurements at high detector counting rates (on the order of 107 s−1 and higher) are relevant for high-temperature plasma diagnostics for existing tokamaks and during the development of gamma ray diagnostic systems for the ITER tokamak under construction. At high loads, to obtain spectra without distortion and with a small amount of dead time, it is necessary to use advanced scintillation detector signal processing methods, which can resolve superimposed pulses. Two algorithms that can be used for digital signal processing of scintillation gamma ray detectors with many piled-up pulses are considered in this article, the fitting and deconvolution methods. These algorithms are compared with both one another and two less sophisticated pulse-height analysis algorithms (maximum height and total sum under the peak) in applications that process model and measured signals. Baseline detection algorithms are also considered, which are necessary when processing signals from detectors. The algorithms are applied to LaBr 3 (Ce) detector signal processing. For the modeled signals, the best results in terms of the number of resolved events and energy resolution at counting rates up to 2 × 107 s−1 of the LaBr 3 (Ce) detector are demonstrated by the fitting method. In the real gamma ray measurements at a loading of 5.1 106 s−1, the deconvolution method demonstrated the best energy resolution. [ABSTRACT FROM AUTHOR]

The proton light yield of organic scintillators has been measured extensively in recent years using fast waveform digitizers and large discrepancies exist in the values reported by different authors. In this letter, we address principles of digital signal processing that must be considered when conducting scintillator light yield measurements. Digitized waveform pulse height values are only proportional to the amount of scintillation light if the temporal shape of the scintillation pulse is independent of the amount of energy deposited. This is not the case for scintillation pulses resulting from fast neutron interactions in organic scintillators. Authors measuring proton light yield should therefore report pulse integral values and ensure that the integration length is long enough to capture most of the scintillation light. [ABSTRACT FROM AUTHOR]

A digital data acquisition system together with MATLAB software for data analysis were utilised to measure the pulse specification of the scintillation detector assembly. Besides, the sensitivity of a photomultiplier tube (PMT) window to gamma-rays was studied to discriminate the signals produced as a result of gamma-ray interactions inside the glass window from those originating from the scintillator cell. The result showed that an algorithm based on the time features was capable to evaluate the contributions of these two different signals. [ABSTRACT FROM AUTHOR]

Coincidence timing resolution (CTR) of 10 ps FWHM would drastically increase the contrast of images in pre-clinical and clinical positron emission tomography (PET) due to the capability to localize the annihilation site along the line of response with unprecedented accuracy. Currently, the scintillators and the photodetectors with their electronic readout are the two limiting factors to reach such a timing resolution. On the photodetector side, the single photon timing resolution (SPTR) must be improved below 4 ps RMS to reach a CTR of 10 ps FWHM. To this end, we propose to use a 3D digital silicon photomultiplier (3DdSiPM) where each single photon avalanche diode (SPAD) has its own quenching circuit (QC) and time-to-digital converter (TDC). To reach an SPTR of 4 ps RMS in an array of SPAD requires to correct each readout pixel individually to minimize the impact of TDC least significant bit (LSB) non-uniformities and SPAD-to-SPAD skew. For this purpose, we developed an array of 256 pixels of SPAD readout circuits optimized for high timing precision with embedded digital signal processing. The latter is a code-to-time conversion where each pixel is individually corrected for TDC LSB variation and skew. Measurement results on single pixels (QC and TDC) show timing jitter down to 8 ps RMS. The uncorrected array timing jitter is about 87 ps RMS and is reduced to 18 ps RMS after skew correction and TDC LSB correction. [ABSTRACT FROM AUTHOR]

The upcoming detector facility aims at developing new state-of-the-art particle detectors as well as providing hands-on training to postgraduate students using both analog and digital signal processing from nuclear radiation detectors. The project is two-fold and aims at developing: 1) ancillary detectors to be coupled with the new GAMKA array at iThemba LABS. Of particular interest to our group is the determination of nuclear shapes, which depend on the hyperfine splitting of magnetic substates; 2) PET scanners for cancer imaging using a cheaper technology. Performance of NaI(Tl) inorganic scintillator detectors has been evaluated using PIXIE-16 modules from XIA digital electronics. Gamma-ray energy spectra were acquired from 60Co and 137Cs radioactive sources to calculate the detector resolution as well as to optimize the digital parameters. The present study focuses on improving and optimizing the slow and fast filter parameters for NaI(Tl) detectors which can eventually be used in the list mode of data aquisition. [ABSTRACT FROM AUTHOR]