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The concept of structure engineering has been proposed for exploring the next generation of radiation detectors with improved performance. A TOF-PET geometry with heterostructured scintillators with a pixel size of 3.0x3.1x15 mm3 was simulated using Monte Carlo. The heterostructures consisted of alternating layers of BGO as a dense material with high stopping power and plastic (EJ232) as a fast light emitter. The detector time resolution was calculated as a function of the deposited and shared energy in both materials on an event-by-event basis. While sensitivity was reduced to 32% for 100 μm thick plastic layers and 52% for 50 μm, the CTR distribution improved to 204±49 ps and 220±41 ps respectively, compared to 276 ps that we considered for bulk BGO. The complex distribution of timing resolutions was accounted for in the reconstruction. We divided the events into three groups based on their CTR and modeled them with different Gaussian TOF kernels. On a NEMA IQ phantom, the heterostructures had better contrast recovery in early iterations. On the other hand, BGO achieved a better contrast to noise ratio (CNR) after the 15th iteration due to the higher sensitivity. The developed simulation and reconstruction methods constitute new tools for evaluating different detector designs with complex time responses.

Sending and receiving information with electromagnetic radiation is fundamental to imaging and communications. Humankind’s ability to utilise this radiation is dependent on how efficiently we can detect it, and improving detectors will advance these technologies. Visible light and X-rays make up two regions of the electromagnetic spectra, both key bands for imaging in different modalities. The visible spectrum represents the energies we can detect with our eyes, while X-rays are highly penetrative and allow the inside of opaque objects to be imaged. While their applications are highly complementary, their detector technologies also share commonalities, allowing the development of both simultaneously. In this thesis, the unique properties of metal halide perovskites are utilised to advance both visible light and Xray detectors. However, other properties of perovskites, such as ion migration, can provide challenges when characterising performance, and so techniques to accurately measure their detecting ability are also developed. Metal halide perovskites are exploited to design two new detector device structures, increasing the functionality of photodetectors and overcoming the existing limitations of direct X-ray detectors. A unique photodetector, utilising the band gap tunability of perovskites, is developed to produce a multiband response that can controllably detect different regions of the visible spectrum. The resulting device is employed in a method to send communications with added encryption. Additionally, a concept for a novel X-ray detecting device is developed, using the ability of perovskites to retain impressive properties after low-temperature solution deposition. The device structure decouples the dimensions of photon absorption and charge carrier collection to retain performance across the X-ray spectrum, overcoming the limitations currently preventing the commercial success of direct X-ray detectors. The potential of perovskites as scintillators for indirect X-ray detection is investigated. The published performances are contextualised with a detailed analysis of the operating mechanism. This mechanistic insight highlights the advantages this material could bring, and we propose the applications that would benefit most from perovskite scintillators, as well as the origins of the remaining limitations. The concurrent understanding of perovskites in other optoelectronic devices is utilised to suggest pathways to overcome the remaining challenges and bring the material closer to commercialisation. These suggestions are applied, and impressive scintillation performance is demonstrated from an emerging Cs2ZrBr6 nanocrystal scintillator system. This work also highlights the specific considerations required when characterising perovskitebased detectors. The large defect density in these materials is shown to be a double-edged sword; making measurements under low light intensities prone to errors, but also acting as another lever to control detection performance. The challenges of characterising direct X-ray detectors are also discussed, alongside the development of experimental procedures to robustly measure halide perovskite devices. Overall, this thesis utilises the unique properties of perovskites to develop detectors with new functionality, whilst ensuring the same properties do not reduce the accuracy when characterising their performance. The work brings perovskite detectors one step closer to a commercial reality.

Time-of-Flight positron emission tomography scanners demand fast and efficient photo sensors and scintillators coupled to fast readout electronics. This article presents the high resolution flexible Time-over-Threshold (HRFlexToT), a 16-channel application-specific-integrated circuit for silicon photomultipliers (SiPM) anode readout manufactured using XFAB 0.18- \mu \text{m} CMOS technology. The main features of the HRFlexToT are a linear Time-over-Threshold with an extended dynamic range (10 bits) for energy measurement, low power consumption (≈ 3.5 mW/ch), and an excellent timing response. The experimental measurements show an energy linearity error of ≈ 3% and an energy resolution of about 12% at 511 keV. Single-photon time resolution measurements performed using an Fondazione Bruno Kessler (FBK) SiPM NUV-HD ( 4 \times 4 mm2 pixel, 40- \mu \text{m} cell) and a Hamamatsu SiPM S13360-3050CS are around 142 and 167 ps full width at half maximum (FWHM), respectively. Coincidence time resolution (CTR) measurements with small cross-section pixelated crystals (LSO:Ce,Ca 0.4%, 2 \times 2 \times 5 mm3) coupled to the same Hamamatsu S13360-3050CS and FBK NUV-HD sensors yield a CTR of 117 ps and 119 ps, respectively. Measurements performed with a large cross-section monolithic crystal (LFS crystal measuring 25 \times 25 \times 20 mm3) and a Hamamatsu SiPM array S13361-6050NE-04 show a CTR of 324 ps FWHM after time-walk and time-skew correction.

Semiconductors are ubiquitous in modern life, existing as transistors in electronics, light emitting diodes in visual displays, and solar cells on houses and company rooftops. Scientists continue to push the limits of material properties to ameliorate the most technologically challenging problems facing humanity, such as climate change, the breakdown of Moore’s law, and the continued need for affordable, widely-available technology for our expanding population. At the heart of semiconductor technology is the necessity to deeply understand and control material-dependent structure-property relationships. However, single-component materials can have trade-offs or intrinsic limitations that hinder further advancement. But with a plethora of semiconductors available, increasingly-clever design of multi-component, hybrid materials with complementary properties have proven instrumental in overcoming intrinsic limitations of single-phase materials. In this work, we utilize organic semiconductors, three-dimensional perovskites, two-dimensional perovskites, and quantum dots to exploit their unique properties to enhance structure-property relationships. In this work, we first combine organic semiconductors with two-dimensional perovskites, and second, we incorporate quantum dot dopants in three-dimensional perovskites. In the first pairing, we leveraged the structural tunability of two-dimensional perovskites to finely control the crystal structure of a small molecule organic semiconductor, 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene), whose propensity to adopt multiple molecular packing motifs with highly-contrasting optoelectronic properties has been an ongoing challenge. Next, we studied singlet fission, an exciton multiplication process with applications in organic photovoltaics, of the perovskite-templated TIPS-pentacene structures to show that a key exciton separation process is enhanced by a factor greater than two when molecular packing structural disorder is reduced. Finally, modeling of TIPS-pentacene/perovskite interfacial structures revealed that perovskite surfaces allow for closer packing of TIPS-pentacene molecules. In the second pairing, we doped three-dimensional perovskite with lead sulfide quantum dots to utilize the outstanding charge carrier mobility of three-dimensional perovskites with the quantum-confined, narrow band emission of the quantum dots for its application as scintillation X-ray detectors. We show that the light yield, a key performance metric for scintillators, of quantum-dot-doped perovskites is substantially improved compared to that reported for single-phase perovskites. These works motivate the interface engineering of hybrid semiconductor material systems to control structural-optoelectronic properties.

The correct quantification of the dose released in charged particle therapy treatments requires the knowledge of the double differential fragmentation cross section of particles composing both the beam and the target. The FragmentatiOn Of Target (FOOT) experiment aims at measuring these cross sections for ions of interest for charged particle therapy applications. This article describes the performance of the time-of-flight (TOF)-wall detector of the experiment. The detector is composed of two layers of 44 cm $\times 2$ cm $\times 3$ mm plastic scintillator bars (20 for each layer), arranged orthogonally and read-out by silicon photomultipliers. The detector is designed to identify the charge of fragments ranging from protons to oxygen ions, with a maximum energy of 700 MeV/u, by measuring the energy released in the scintillators and the TOF with respect to a start counter. In this study, the detector was scanned with carbon ions of energy between 115 and 400 MeV/u and with a 60-MeV proton beam. The measurements show an energy resolution ( $\sigma _{E}/\mu _{E}$ ) between 6% and 4% and a contribution of the detector to the TOF system time resolution between 25 and 20 ps (standard deviation) for carbon ions and between 100 and 80 ps for protons.

The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7 × 6 × 7.2 m3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP's successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components.

This research focuses on LPE growth, and the examination of the optical and photovoltaic properties of single crystalline film (SCF) phosphors based on Ce3+-doped Y3MgxSiyAl5−x−yO12 garnets with Mg and Si contents in x = 0–0.345 and y = 0–0.31 ranges. The absorbance, luminescence, scintillation, and photocurrent properties of Y3MgxSiyAl5−x−yO12:Ce SCFs were examined in comparison with Y3Al5O12:Ce (YAG:Ce) counterpart. Especially prepared YAG:Ce SCFs with a low (x, y < 0.1) concentration of Mg2+ and Mg2+–Si4+ codopants also showed a photocurrent that increased with rising Mg2+ and Si4+ concentrations. Mg2+ excess was systematically present in as-grown Y3MgxSiyAl5−x−yO12:Ce SCFs. The as-grown SCFs of these garnets under the excitation of α–particles had a low light yield (LY) and a fast scintillation response with a decay time in the ns range due to producing the Ce4+ ions as compensators for the Mg2+ excess. The Ce4+ dopant recharged to the Ce3+ state after SCF annealing at T > 1000 °C in a reducing atmosphere (95%N2 + 5%H2). Annealed SCF samples exhibited an LY of around 42% and similar scintillation decay kinetics to those of the YAG:Ce SCF counterpart. The photoluminescence studies of Y3MgxSiyAl5−x−yO12:Ce SCFs provide evidence for Ce3+ multicenter formation and the presence of an energy transfer between various Ce3+ multicenters. The Ce3+ multicenters possessed variable crystal field strengths in the nonequivalent dodecahedral sites of the garnet host due to the substitution of the octahedral positions by Mg2+ and the tetrahedral positions by Si4+. In comparison with YAG:Ce SCF, the Ce3+ luminescence spectra of Y3MgxSiyAl5−x−yO12:Ce SCFs greatly expanded in the red region. Using these beneficial trends of changes in the optical and photocurrent properties of Y3MgxSiyAl5−x−yO12:Ce garnets as a result of Mg2+ and Si4+ alloying, a new generation of SCF converters for white LEDs, photovoltaics, and scintillators could be developed.

The effective prompt response function full width at half maximum, PRF FWHM of 637 ps (obtained from the prompt gamma pairs of 477 keV and 700 keV associated with the yrast 2+ state in 206Po), and 1007 ps (obtained from the Compton gamma pairs of 189 keV and 237 keV associated with the 192Os(18O,16O)194Os 2 neutron transfer reaction) were used in fitting the time difference spectra obtained from the gamma coincident pairsof 206 keV and 374 keV in a symmetrised LaBr3(Ce) associated with the gamma transitions in 192Os, using the Half-life program. The values of half-life measured by fitting these PRF FWHM of 637 ps and 1007 ps separately show an excellent agreement of 282(16) ps and 272(21) ps, respectively, which correspond to the global half-life value of 282(4) ps for the 192Os. The mean value of 277(12) ps from these two measurements was used in calculating the B(E2; IL ->IL-2) of 4233(114) e2fm4, which is equivalent to be 81(19) W.u.

The timing characteristics of scintillators must be understood in order to determine which applications they are appropriate for. Polyethylene naphthalate (PEN) and polyethylene teraphthalate (PET) are common plastics with uncommon scintillation properties. Here, we report the timing characteristics of PEN and PET, determined by exciting them with 120 GeV protons. The test beam was provided by Fermi National Accelerator Laboratory, and the scintillators were tested at the Fermilab Test Beam Facility. PEN and PET are found to have dominant decay constants of 34.91 ns and 6.78 ns, respectively., Comment: 5 pages, 3 figures

Agradecimentos: The ProtoDUNE-SP detector was constructed and operated on the CERN Neutrino Platform. We gratefully acknowledge the support of the CERN management, and the CERN EP, BE, TE, EN and IT Departments for NP04/ProtoDUNE-SP. This document was prepared by the DUNE collaboration using the resources of the Fermi National Accelerator Laboratory (Fermilab) , a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by FermiResearch Alliance, LLC (FRA) , acting under Contract No. DE-AC02-07CH11359. This work was supported by CNPq, FAPERJ, FAPEG and FAPESP, Brazil; CFI, IPP and NSERC, Canada; CERN; MSMT, Czech Republic; ERDF, H2020-EU and MSCA, European Union; CNRS/IN2P3 and CEA, France; INFN, Italy; FCT, Portugal; NRF, South Korea; CAM, Fundacion "La Caixa", Junta de Andalucfa-FEDER, and MICINN, Spain; SERI and SNSF, Switzerland; TuBiTAK, Turkey; The Royal Society and UKRI/STFC, United Kingdom; DOE and NSF, United States of America. This research used resources of the National Energy Research Scientific Computing Center (NERSC) , a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231 Abstract: The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7 x 6 x 7.2 m3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP's successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJ FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁS - FAPEG FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Aberto

The multi-TeV energy region of the cosmic-ray spectra has been recently explored by direct detection experiments that used calorimetric techniques to measure the energy of the cosmic particles. Interesting spectral features have been observed in both all-electron and nuclei spectra. However, the interpretation of the results is compromised by the disagreements between the data obtained from the various experiments, that are not reconcilable with the quoted experimental uncertainties. Understanding the reason for the discrepancy among the measurements is of fundamental importance in view of the forthcoming high-energy cosmic-ray experiments planned for space, as well as for the correct interpretation of the available results. The purpose of this work is to investigate the possibility that a systematic effect may derive from the non-proportionality of the light response of inorganic crystals, typically used in high-energy calorimetry due to their excellent energy-resolution performance. The main reason for the non-proportionality of the crystals is that scintillation light yield depends on ionisation density. Experimental data obtained with ion beams were used to characterize the light response of various scintillator materials. The obtained luminous efficiencies were used as input of a Monte Carlo simulation to perform a comparative study of the effect of the light-yield non-proportionality on the detection of high-energy electromagnetic and hadronic showers. The result of this study indicates that, if the calorimeter response is calibrated by using the energy deposit of minimum ionizing particles, the measured shower energy might be affected by a significant systematic shift, at the level of few percent, whose sign and magnitude depend specifically on the type of scintillator material used., Comment: to be published in JINST

The T2K experiment widely uses plastic scintillator as a target for neutrino interactions and an active medium for the measurement of charged particles produced in neutrino interactions at its near detector complex. Over 10 years of operation the measured light yield recorded by the scintillator based subsystems has been observed to degrade by 0.9--2.2\% per year. Extrapolation of the degradation rate through to 2040 indicates the recorded light yield should remain above the lower threshold used by the current reconstruction algorithms for all subsystems. This will allow the near detectors to continue contributing to important physics measurements during the T2K-II and Hyper-Kamiokande eras. Additionally, work to disentangle the degradation of the plastic scintillator and wavelength shifting fibres shows that the reduction in light yield can be attributed to the ageing of the plastic scintillator., Comment: 29 pages, 18 figures. Prepared for submission to JINST

HERMES (High Energy Rapid Modular Ensemble of Satellites) is a space-borne mission based on a constellation of six 3U CubeSats flying in a low-Earth orbit, hosting new miniaturized instruments based on a hybrid Silicon Drift Detector/GAGG:Ce scintillator photodetector system sensitive to X-rays and gamma-rays. Moreover, the HERMES constellation will operate in conjunction with the Australian-Italian Space Industry Responsive Intelligent Thermal (SpIRIT) 6U CubeSat, that will carry in a Sun-synchronous orbit (SSO) an actively cooled HERMES detector system payload. In this paper we provide an overview of the ground calibrations of the first HERMES and SpIRIT flight detectors, outlining the calibration plan, detector performance and characterization., Comment: 9 pages, 7 figures. Proceedings of SPIE Astronomical Telescopes and Instrumentation 2022

Metal halide perovskites have recently been reported as excellent scintillators for X-ray detection. However, perovskite based scintillators are susceptible to moisture and oxygen atmosphere, such as the water solubility of CsPbBr3, and oxidation vulnerability of Sn2+, Cu+. The traditional metal halide scintillators (NaI: Tl, LaBr3, etc.) are also severely restricted by their high hygroscopicity. Here we report a new kind of lead free perovskite with excellent water and radiation stability, Rb2Sn1-x Te x Cl6. The equivalent doping of Te could break the in-phase bonding interaction between neighboring octahedra in Rb2SnCl6, and thus decrease the electron and hole dimensionality. The optimized Te content of 5% resulted in high photoluminescence quantum yield of 92.4%, and low X-ray detection limit of 0.7 µGyair s−1. The photoluminescence and radioluminescence could be maintained without any loss when immersing in water or after 480,000 Gy radiations, outperforming previous perovskite and traditional metal halides scintillators.

This manuscript summarizes recent results on the development of composite luminescent materials based on the single-crystalline films and single crystals of simple and mixed garnet compounds obtained by the liquid-phase epitaxy growth method. Such composite materials can be applied as scintillating and thermoluminescent (TL) detectors for radiation monitoring of mixed ionization fluxes, as well as scintillation screens in the microimaging techniques. The film and crystal parts of composite detectors were fabricated from efficient scintillation/TL materials based on Ce3+-, Pr3+-, and Sc3+-doped Lu3Al5O12 garnets, as well as Ce3+-doped Gd3−xAxAl5−yGayO12 mixed garnets, where A = Lu or Tb; x = 0–1; y = 2–3 with significantly different scintillation decay or positions of the main peaks in their TL glow curves. This work also summarizes the results of optical study of films, crystals, and epitaxial structures of these garnet compounds using absorption, cathodoluminescence, and photoluminescence. The scintillation and TL properties of the developed materials under α- and β-particles and γ-quanta excitations were studied as well. The most efficient variants of the composite scintillation and TL detectors for monitoring of composition of mixed beams of ionizing radiation were selected based on the results of this complex study.

The Nucleus experiment aims to measure coherent elastic neutrino nucleus scattering of reactor anti-neutrinos using cryogenic calorimeters. Operating at an overburden of 3 meters of water equivalent, muon-induced backgrounds are expected to be one of the dominant background contributions. Besides a high efficiency to identify muon events passing the experimental setup, the Nucleus muon veto has to fulfill tight spatial requirements to fit the constraints given by the experimental site and to minimize the induced detector dead-time. We developed highly efficient and compact muon veto modules based on plastic scintillators equipped with wavelength shifting fibers and silicon photo multipliers to collect and detect the scintillation light. In this paper, we present the full characterization of a prototype module with different light read-out configurations. We conclude that an efficient and compact muon veto system can be built for the Nucleus experiment from a cube assembly of the developed modules. Simulations show that an efficiency for muon identification of >99 % and an associated rate of 325 Hz is achievable, matching the requirements of the Nucleus experiment.

An imaging heavy ion beam probe (i-HIBP) diagnostic, for the simultaneous measurement of plasma density, magnetic field and electrostatic potential in the plasma edge, has been installed at ASDEX Upgrade. Unlike standard heavy ion beam probes, in the i-HIBP the probing (heavy) ions are collected by a scintillator detector, creating a light pattern or strike-line, which is then imaged by a camera. Therefore, a good characterization of the scintillator response is needed. Previous works focused on the scintillator behaviour against irradiation with light ions such as hydrogen and alpha particles. In this work we present the characterization of several scintillator screens - TG-Green (SrGa2S4:Eu2+), YAG-Ce (Y3Al5O12:Ce3+) and P11 (ZnS:Ag) - against irradiation with 133Cs+ ions, in an energy range between 5 and 70 keV and ion currents between 105 and 107 ions/(s·cm2). Three main properties of the scintillators have been studied: the ionolumenescence efficiency or yield, the linearity and the degradation as a function of the fluence. The highest yield was delivered by the TG-Green scintillator screen with > 8·103 photons/ion at 50 keV. All the samples showed a linear response with increasing incident ion flux. The degradation was quantified in terms of the fluence F1/2, which leads to a reduction of the emissivity by a factor of 2. TG-Green showed the lowest degradation with F1/2= 5.4·1014 ions/cm2. After the irradiation the samples were analyzed by Scanning Electron Microscopy (SEM), Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE). No trace of Cs was found in the irradiated regions. These results indicate that, among the tested materials, TG-Green is the best candidate for the i-HIBP detector., This work received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 805162). G. Birkenmeier acknowledges funding from the Helmholtz Association under grant no. VHNG-1350. J. Galdon-Quiroga acknowledges funding from the Spanish Ministry of Science and Innovation under grant no. FJC2019-041092-I.

In proton therapy, the dose from secondary neutrons to the patient can contribute to side effects and the creation of secondary cancer. A simple and fast detection system to distinguish between dose from protons and neutrons both in pretreatment verification as well as potentially in vivo monitoring is needed to minimize dose from secondary neutrons. Two 3 mm long, 1 mm diameter organic scintillators were tested for candidacy to be used in a proton–neutron discrimination detector. The SCSF-3HF (1500) scintillating fibre (Kuraray Co. Chiyoda-ku, Tokyo, Japan) and EJ-260 plastic scintillator (Eljen Technology, Sweetwater, TX, USA) were irradiated at the TRIUMF Neutron Facility and the Proton Therapy Research Centre. In the proton beam, we compared the raw Bragg peak and spread-out Bragg peak response to the industry standard Markus chamber detector. Both scintillator sensors exhibited quenching at high LET in the Bragg peak, presenting a peak-to-entrance ratio of 2.59 for the EJ-260 and 2.63 for the SCSF-3HF fibre, compared to 3.70 for the Markus chamber. The SCSF-3HF sensor demonstrated 1.3 times the sensitivity to protons and 3 times the sensitivity to neutrons as compared to the EJ-260 sensor. Combined with our equations relating neutron and proton contributions to dose during proton irradiations, and the application of Birks’ quenching correction, these fibres provide valid candidates for inexpensive and replicable proton-neutron discrimination detectors.

Fast and heavy inorganic scintillators with suitable radiation tolerance are required to face the challenges presented at future hadron colliders of high energy and intensity. Up to 5 GGy and 5 × 1018 neq/cm2 of one-MeV-equivalent neutron fluence is expected by the forward calorimeter at the Future Hadron Circular Collider. This paper reports the results of an investigation of proton- and neutron-induced radiation damage in various fast and heavy inorganic scintillators, such as LYSO:Ce crystals, LuAG:Ce ceramics, and BaF2 crystals. The experiments were carried out at the Blue Room with 800 MeV proton fluence up to 3.0 × 1015 p/cm2 and at the East Port with one MeV equivalent neutron fluence up to 9.2 × 1015 neq/cm2, respectively, at the Los Alamos Neutron Science Center. Experiments were also carried out at the CERN PS-IRRAD proton facility with 24 GeV proton fluence up to 8.2 × 1015 p/cm2. Research and development will continue to develop LuAG:Ce ceramics and BaF2:Y crystals with improved optical quality, F/T ratio, and radiation hardness.

The first time-of-flight positron emission tomography (TOF-PET) scanners were developed as early as in the 1980s. However, the poor light output and low detection efficiency of TOF-capable detectors available at the time limited any gain in image quality achieved with these TOF-PET scanners over the traditional non-TOF PET scanners. The discovery of LSO and other Lu-based scintillators revived interest in TOF-PET and led to the development of a second generation of scanners with high sensitivity and spatial resolution in the mid-2000s. The introduction of the silicon photomultiplier (SiPM) has recently yielded a third generation of TOF-PET systems with unprecedented imaging performance. Parallel to these instrumentation developments, much progress has been made in the development of image reconstruction algorithms that better utilize the additional information provided by TOF. Overall, the benefits range from a reduction in image variance (SNR increase), through allowing joint estimation of activity and attenuation, to better reconstructing data from limited angle systems. In this work, we review these developments, focusing on three broad areas: 1) timing theory and factors affecting the time resolution of a TOF-PET system; 2) utilization of TOF information for improved image reconstruction; and 3) quantification of the benefits of TOF compared to non-TOF PET. Finally, we offer a brief outlook on the TOF-PET developments anticipated in the short and longer term. Throughout this work, we aim to maintain a clinically driven perspective, treating TOF as one of multiple (and sometimes competitive) factors that can aid in the optimization of PET imaging performance. ispartof: IEEE Transactions on Radiation and Plasma Medical Sciences vol:5 issue:5 pages:598-618 ispartof: location:United States status: published

The paper addresses the development of composite scintillation materials providing simultaneous real-time monitoring of different types of ionizing radiation (α-, β-particles, γ-rays) in mixed fluxes of particles and quanta. The detectors are based on composite heavy oxide scintillators consisting of a thin single-crystalline film and a bulk single-crystal substrate. The film and substrate respond to certain types of ionizing particles, forming together an all-in-one composite scintillator capable of distinguishing the type of radiation through the different time characteristics of the scintillation response. Here, we report the structure, composition, and scintillation properties under different ionizing radiations of (Lu,Gd,Tb)3(Al,Ga)5O12:Ce films deposited using liquid phase epitaxy onto Gd3(Al1−xGax)5O12:Ce (GAGG:Ce) single-crystal substrates. The most promising compositions with the highest light yields and the largest differences in scintillation decay timing under irradiation with α-, β-particles, and γ-rays were selected. Such detectors are promising for environmental security purposes, medical tomography, and other radiation detection applications.

Neutron detectors perform key tasks in many research fields as nuclear, particle and astroparticle physics as well as neutron dosimetry, radiotherapy, and radiation protection. Neutron detectors exhibiting tracking capability are still missing, although several approaches to neutron momentum reconstruction have been proposed. In this context, we aim at developing a novel RecoIl-Proton Track Imaging DEtection system “RIPTIDE”, in which the light output of a fast scintillation signal is used to perform a complete reconstruction in space and time of the neutron-proton elastic scattering. The 3D track reconstruction is going to be implemented by state-of-the-art high-sensitivity imaging detector (CMOS, MCP-Timepix). Preliminary Geant4 simulations of the proposed set-up show up a good detection efficiency in a compact active volume. The envisaged electronic readout can be easily adapted according to a specific application (event-by-event mode or integration mode). The system can be rescaled by increasing the detection volume or by combining several detection modules. Further developments of the basic detection technique can be adapted for fast charged particle detection tracking as well.

A liquid scintillator consisting of linear alkylbenzene as the solvent and 2,5-diphenyloxazole as the fluor was developed for the SNO+ experiment. This mixture was chosen as it is compatible with acrylic and has a competitive light yield to pre-existing liquid scintillators while conferring other advantages including longer attenuation lengths, superior safety characteristics, chemical simplicity, ease of handling, and logistical availability. Its properties have been extensively characterized and are presented here. This liquid scintillator is now used in several neutrino physics experiments in addition to SNO+.

A synthetic fast-ion loss (FIL) detector and an imaging Heavy Ion Beam Probe (i-HIBP) have been implemented in the 3D hybrid kinetic-magnetohydrodynamic code MEGA. First synthetic measurements from these two diagnostics have been obtained for neutral beam injection-driven Alfvén Eigenmode (AE) simulated with MEGA. The synthetic FILs show a strong correlation with the AE amplitude. This correlation is observed in the phase-space, represented in coordinates (P, E), being toroidal canonical momentum and energy, respectively. FILs and the energy exchange diagrams of the confined population are connected with lines of constant E, a linear combination of E and P. First i-HIBP synthetic signals also have been computed for the simulated AE, showing displacements in the strike line of the order of ∼1 mm, above the expected resolution in the i-HIBP scintillator of ∼100 μm., This work received funding from the European Starting Grant (ERC) from project 3D-FIREFLUC and from the Spanish Ministry of Science under Grant No. FPU19/02267. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.

The JET FILD is a scintillator-based Fast-ion Loss Detector optimized to measure fusion-born alpha-particle losses. This work covers its upgrade and absolute calibration in preparation for the following JET DT experiments. A fast scintillator material (TG-Green) has been installed in the JET FILD. A heater jacket is installed around the fiber bundle, responsible for transmitting the light from the scintillator plate, to anneal the fiber obscuring due to neutron damage. The JET FILD has been upgraded with a 1 Mpx camera and 2 MHz photomultiplier data acquisition hardware. Full-orbit simulations give an estimate of the shading effects on the scintillator plate of the first wall structures and provide a synthetic signal of the JET FILD. A detector instrument function enables absolute values of fast-ion losses using calibration factors. The calibration factors are made available in a shot-to-shot basis for the characterized species and energies and with corrections for the diagnostic conditions. The fast acquisition system sets the Nyquist frequency (1 MHz) above the typical mode frequencies (≈10 kHz), thus making it possible to identify MHD-induced fast-ion losses., This work was carried out within the framework of the EUROfusion Consortium and received funding from the Euratom Research and Training Programme 2014–2018 and 2019–2020 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. This research received funding from the V Plan Propio de Investigación de la Universidad de Sevilla (Grant No. PP2016-7145). This scientific work was partly supported by the Polish Ministry of Science and Higher Education within the framework of the scientific financial resources in the year 2020 allocated for the realization of the international co-financed project (No. 5118/H2020/EURATOM/2020/2).

Data Availability Statement The ASIC presented in this study is available through SCIENTIFICA INTERNATIONAL, S.L.U. Check the website: https://www.scientifica.es/, accessed on 1 January 2021., The 8-channel Multiple Use Silicon Photo-multiplier (SiPM) Integrated Circuit (MUSIC) Application specific integrated circuit (ASIC) for SiPM anode readout has been designed for applications where large photo-detection areas are required. MUSIC offers three main features: (1) Sum of the eight input channels using a differential output driver, (2) eight individual single ended (SE) analog outputs, and (3) eight individual SE binary outputs using a time over threshold technique. Each functionality, summation and individual readout includes a selectable dual-gain configuration. Moreover, the signal sum implements a dual-gain output providing a 15-bit dynamic range. The circuit contains a tunable pole zero cancellation of the SiPM recovery time constant to deal with most of the available SiPM devices in the market. Experimental tests show how MUSIC can linearly sum signals from different SiPMs and distinguish even a few photons. Additionally, it provides a single photon output pulse width at half maximum (FWHM) between 5–10 ns for the analog output and a single-photon time resolution (SPTR) around 118 ps sigma using a Hamamatsu SiPM S13360-3075CS for the binary output. Lastly, the summation mode has a power consumption of ≈200 mW, whereas the individual readout consumes ≈30 mW/ch., Marc Ribó acknowledges support by the Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN), grant FPA2017-82729-C6-2-R (AEI/FEDER, UE) and grant PID2019-104114RB-C33/AEI/10.13039/501100011033. We also acknowledge financial support from the State Agency for Research of the Spanish Ministry of Science and Innovation through the “Unit of Excellence María de Maeztu 2020-2023” award to the Institute of Cosmos Sciences (CEX2019-000918-M).

peer-reviewed Radiation dosimetry plays a crucial role in the quality assurance in radiotherapy. To date, this is limited to monitoring the overall dose over the complete beam time, and so, there is limited information on the actual beam quality. An optical fibre sensor is developed based on cerium-doped yttrium aluminum garnet (YAG:Ce) scintillator. The temporal resolution and the stability of this scintillator-based optical fibre sensor have been experimentally evaluated and directly compared with similarly fabricated sensors based on terbium activated gadolinium oxysulfide and commercial plastic scintillating fibre, BCF-12. The photon yield and repeatability of the YAG-based sensor are compared in the clinical setting with the BCF-12 sensor and both show a high stability. The coefficient of variation of the YAG sensor is 0.7%, which is lower than the BCF sensor with a coefficient of variation of 1.4%.

In this paper, an FPGA-based plain delay line time-to-digital converters (TDC) is presented, together with a theoretical model on its timing properties. The TDC features an automated calibration system implemented in the on-chip processor of an SoC-FPGA, uses a low amount of FPGA resources and is therefore suitable for applications requiring a high number of channels, such as time-of-flight positron emission tomography (PET). We first investigated the importance of calibration and validated the theoretical model on the TDC timing properties. Finally, the device has been embodied into a two channel PET acquisition system and tested. We found the calibration essential to obtain a good time resolution (38-ps FWHM in comparison with a 78-ps FWHM obtained with the uncalibrated device). The model we developed is able to predict the TDC timing properties. They are shown to be related to the fundamental parameters of the used FPGA technology. In particular, the best achievable time resolution of this specific architecture (plain tapped delay line on FPGA) is set to about 30 ps by the sum of the setup and hold times of the registers in the FPGA. The timing resolution of the two-channel setup is about 118 ps.

Typically, a time-of-flight (TOF) positron emission tomography (PET) block detector is built using application-specific integrated circuits (ASICs), since they integrate a high number of channels at a reasonable power consumption and into a small area. However, ASICs' flexibility is limited and prototyping times are long because a semiconductor fabrication process is required in every design iteration. Alternatively, fast terminal (FT) silicon photomultipliers (SiPMs) require a simplified analog front-end in order to achieve TOF accuracy. In addition, field-programmable gate arrays (FPGAs) can allocate time-to-digital converters as well as complex digital readout logics. In this paper, we propose building TOF-PET block detectors based on FPGAs, FT-SiPMs, and minimal amount of off-the-shelf components. In this way, TOE-PET accuracy is achieved with a full-flexible and fast prototyping solution. We evaluated the coincidence resolving time, performance degradations due to channel multiplexing, energy resolution, and scintillator pixel encoding performance of SiPM arrays utilizing the proposed approach. Experimental results show minimal timing degradations, when multiplexing FTs. Moreover, simulation results show a low reduction in the singles count rate of multiplexed channels at typical brain-PET radioactive doses.

YPO4 phosphors doped with trivalent ion Pr3+ were prepared by sol–gel method and treated with different doses of gamma radiation, from 0.25 MGy to 4 MGy. Effects of radiation on morphology, structure and luminescent properties were analyzed. Also, the influence of radiation on the change in the color of the samples was examined. The color efficiency of powders was evaluated by colorimetric analysis (CIE and L * a * b system). It has been observed that powders change color under the influence of radiation, i.e. they pass from white to pinkish red. Also, it has been determined that the radiation affects morphology change, as the particle size increases with increasing of the radiation dose. With the increase in the radiation dose, the emission intensity of samples decreases. The structure remains almost unchanged after irradiation, and the intensity constantly decreases with increasing of dose. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.

International audience; MultiLayer Phoswich (MLP) scintillators have been studied for fission neutron detection by Monte-Carlo simulations and experimental tests. n/γ discrimination behavior of these systems and their angular dependencies have been characterized. The possibility to carry on a neutron counting system based of such an approach has been proven, and according to the results, an optimal thickness of layers for fission neutron counting was found around [100–150] μm. But, contrary to current liquid or solid-state discrimination scintillators, it appears that MLP-based neutron counting systems cannot directly classify neutron and gamma-ray interaction events from pulse shape analysis. To operate properly, it is therefore required to implement a compensation algorithm in the system readout.

A scintillating bolometer based on a large cubic Li$_{2}$$^{100}$MoO$_4$ crystal (45 mm side) and a Ge wafer (scintillation detector) has been operated in the CROSS cryogenic facility at the Canfranc underground laboratory in Spain. The dual-readout detector is a prototype of the technology that will be used in the next-generation $0\nu2\beta$ experiment CUPID. The measurements were performed at 18 and 12 mK temperature in a pulse tube dilution refrigerator. This setup utilizes the same technology as the CUORE cryostat that will host CUPID and so represents an accurate estimation of the expected performance. The Li$_{2}$$^{100}$MoO$_4$ bolometer shows a high energy resolution of 6 keV FWHM at the 2615 keV $\gamma$ line. The detection of scintillation light for each event triggered by the Li$_{2}$$^{100}$MoO$_4$ bolometer allowed for a full separation ($\sim$8$\sigma$) between $\gamma$($\beta$) and $\alpha$ events above 2 MeV. The Li$_{2}$$^{100}$MoO$_4$ crystal also shows a high internal radiopurity with $^{228}$Th and $^{226}$Ra activities of less than 3 and 8 $\mu$Bq/kg, respectively. Taking also into account the advantage of a more compact and massive detector array, which can be made of cubic-shaped crystals (compared to the cylindrical ones), this test demonstrates the great potential of cubic Li$_{2}$$^{100}$MoO$_4$ scintillating bolometers for high-sensitivity searches for the $^{100}$Mo $0\nu2\beta$ decay in CROSS and CUPID projects.

A scintillating bolometer based on a large cubic Li$_{2}$$^{100}$MoO$_4$ crystal (45 mm side) and a Ge wafer (scintillation detector) has been operated in the CROSS cryogenic facility at the Canfranc underground laboratory in Spain. The dual-readout detector is a prototype of the technology that will be used in the next-generation $0 u2\beta$ experiment CUPID. The measurements were performed at 18 and 12 mK temperature in a pulse tube dilution refrigerator. This setup utilizes the same technology as the CUORE cryostat that will host CUPID and so represents an accurate estimation of the expected performance. The Li$_{2}$$^{100}$MoO$_4$ bolometer shows a high energy resolution of 6 keV FWHM at the 2615 keV $\gamma$ line. The detection of scintillation light for each event triggered by the Li$_{2}$$^{100}$MoO$_4$ bolometer allowed for a full separation ($\sim$8$\sigma$) between $\gamma$($\beta$) and $\alpha$ events above 2 MeV. The Li$_{2}$$^{100}$MoO$_4$ crystal also shows a high internal radiopurity with $^{228}$Th and $^{226}$Ra activities of less than 3 and 8 $\mu$Bq/kg, respectively. Taking also into account the advantage of a more compact and massive detector array, which can be made of cubic-shaped crystals (compared to the cylindrical ones), this test demonstrates the great potential of cubic Li$_{2}$$^{100}$MoO$_4$ scintillating bolometers for high-sensitivity searches for the $^{100}$Mo $0 u2\beta$ decay in CROSS and CUPID projects.

This article describes the design, assembly and characterization of a portable cosmic ray detector, developed by the INSULAB group and suitable for teaching activities aimed at high school students. It consists of a compact aluminum suitcase containing three plastic scintillator modules coupled to photomultipliers, readout by a custom compact electronics chain and powered by a power bank. The modules operate in coincidence and the system records the arrival time of each particle and the time over threshold of the signal of each scintillator module. The data are acquired and processed by a Raspberry PI connected to a touch screen display for online monitoring. The procedure implemented for the determination of the detector efficiency is reported, along with the results of the measurements of the cosmic ray rate as a function of the altitude and the zenith angle, performed in the laboratory and in different locations outdoors.

An Imaging Neutral Particle Analyzer (INPA) diagnostic has been designed for the ASDEX Upgrade (AUG) tokamak. The AUG INPA diagnostic will measure fast neutrals escaping the plasma after charge exchange reactions. The neutrals will be ionized by a 20 nm carbon foil and deflected toward a scintillator by the local magnetic field. The use of a neutral beam injector (NBI) as an active source of neutrals will provide radially resolved measurements, while the use of a scintillator as an active component will allow us to cover the whole plasma along the NBI line with unprecedented phase-space resolution (, This project received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 805162) and the Spanish Ministerio de Ciencia, Innovación y Universidades (Grant No. FPU19/02486).

This paper presented a new detector module consisting of a micropixel avalanche photodiode (MAPD-3NM), LaBr3:Ce scintillator, and a compact read-out interface system for detecting gamma-rays in a wide energy range. The MAPD array (4 x 4 channels) was assembled using a single MAPD-3NM characterized by its high photon detection efficiency (similar to 25%), pixel density (10000 pixel s/mm(2)), low operation voltage (74.5 V), and low dark current. An active area of a single MAPD-3NM was 3.7 x 3.7 mm(2), while this value was 17 x 17 mm(2) for the assembled array with pixel density of 2190000. The size of the tested LaBr3:Ce scintillator was 15 x 15 x 15 mm(3). According to the characteristics of the detector module, a compact read-out interface device (SPECTRIG MAPD) was developed. SPECTRIG MAPD was designed as a miniature device with low power consumption, which continues to provide a wide spectrum of functions needed for measurement and test silicon photomultipliers (SiPM) and scintillation detectors on their basis. The various experiments were implemented to test the detection performance of a detector module to gamma radiation in the range from 30 keV to 4400 keV.

Agradecimentos: This work was funded by the INFN GERDA/LEGEND and DUNE projects, and in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001 and FAPESP Abstract: In the Deep Underground Neutrino Experiment (DUNE), the VUV LAr luminescence is collected by light trap devices named X-Arapuca, sizing similar to (480 x 93) mm(2) Six thousand of these units will be deployed in the first DUNE ten kiloton far detector module. In this work we present the first characterisation of the photon detection efficiency of an X-Arapuca device sizing similar to(200 x 75) mm(2) via a complete and accurate set of measurements along the cell longitudinal axis with a movable Am-241 source. The MPPCs photosensors are readout by a cryogenic trans-impedance amplifier to enhance the single photoelectron sensitivity and improve the signal-to-noise while ganging 8 MPPC for a total surface of 288 mm(2) Moreover, we developed a new photon downshifting polymeric material, by which the X-Arapuca photon detection efficiency was enhanced of about +50% with respect to the baseline off-shell product deployed in the standard device configuration. The achieved results are compared to previous measurements on a half size X-Arapuca device, with a fixed source facing the center, with no cold amplification stage, and discussed in view of the DUNE full size optical cell construction for both the horizontal and the vertical drift configurations of the DUNE TPC design and in view of liquid Argon doping by ppms of Xe. Other particle physics projects adopting Liquid Argon as target or active veto, such as Dark Side and LEGEND or the DUNE Near Detector, may take advantage of this novel wavelength shifting material COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

CMS MTD collaboration: et al., The MIP Timing Detector will provide additional timing capabilities for detection of minimum ionizing particles (MIPs) at CMS during the High Luminosity LHC era, improving event reconstruction and pileup rejection. The central portion of the detector, the Barrel Timing Layer (BTL), will be instrumented with LYSO:Ce crystals and Silicon Photomultipliers (SiPMs) providing a time resolution of about 30 ps at the beginning of operation, and degrading to 50-60 ps at the end of the detector lifetime as a result of radiation damage. In this work, we present the results obtained using a 120 GeV proton beam at the Fermilab Test Beam Facility to measure the time resolution of unirradiated sensors. A proof-of-concept of the sensor layout proposed for the barrel region of the MTD, consisting of elongated crystal bars with dimensions of about 3×3×57 mm3 and with double-ended SiPM readout, is demonstrated. This design provides a robust time measurement independent of the impact point of the MIP along the crystal bar. We tested LYSO:Ce bars of different thickness (2, 3, 4 mm) with a geometry close to the reference design and coupled to SiPMs manufactured by Hamamatsu and Fondazione Bruno Kessler. The various aspects influencing the timing performance such as the crystal thickness, properties of the SiPMs (e.g. photon detection efficiency), and impact angle of the MIP are studied. A time resolution of about 28 ps is measured for MIPs crossing a 3 mm thick crystal bar, corresponding to a most probable value (MPV) of energy deposition of 2.6 MeV, and of 22 ps for the 4.2 MeV MPV energy deposition expected in the BTL, matching the detector performance target for unirradiated devices., We acknowledge the support provided to the MTD project by the following funding agencies: CERN; Academy of Finland, MEC, and HIP (Finland); CEA (France); NKFIH, OTKA-131991 (Hungary); INFN (Italy); NRF-2008-00460, 2018R1A6A1A06024970, 2020R1A2C1012322 (Republic of Korea); LAS (Lithuania); FCT (Portugal); MON, Rosatom, RAS, RFBR, and NRC KI (Russia); SEIDI, CPAN, PCTI, and FEDER (Spain); Swiss Funding Agencies (Switzerland); DOE and NSF (U.S.A.).

An organic glass scintillator developed by Sandia National Laboratories was characterized in terms of its light output and pulse shape discrimination (PSD) properties and compared to commercial liquid (EJ-309) and plastic (EJ-276) organic scintillators. The electron light output was determined through relative comparison of the $^{137}$Cs Compton edge location. The proton light yield was measured using a double time-of-flight technique at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. Using a tunable broad-spectrum neutron source and an array of pulse-shape-discriminating observation scintillators, a continuous measurement of the proton light yield was performed for EJ-309 (200 keV$-$3.2 MeV), EJ-276 (170 keV$-$4.9 MeV), and the organic glass (50 keV$-$20 MeV). Finally, the PSD properties of the organic glass, EJ-309, and EJ-276 were evaluated using an AmBe source and compared via a figure-of-merit metric. The organic glass exhibited a higher electron light output than both EJ-309 and EJ-276. Its proton light yield and PSD performance were comparable to EJ-309 and superior to that of EJ-276. With these performance characteristics, the organic glass scintillator is well poised to replace current state-of-the-art PSD-capable scintillators in a range of fast neutron detection applications., 32 pages, 13 figures, 9 tables

Poly Ethylene Naphthalate (PEN) is an industrial polymer plastic which is investigated as a low background, transparent, scintillating and wavelength shifting structural material. PEN scintillates in the blue region and has excellent mechanical properties both at room and cryogenic temperatures. Thus, it is an ideal candidate for active structural components in experiments for the search of rare events like neutrinoless double-beta decay or dark matter recoils. Such optically active structures improve the identification and rejection efficiency of backgrounds events, like this improving the sensitivity of experiments. This paper reports on the production of radiopure and transparent PEN plates These structures can be used to mount germanium detectors operating in cryogenic liquids (LAr, LN). Thus, as first application PEN holders will be used to mount the Ge detectors in the Legend-200 experiment. The whole process from cleaning the raw material to testing the PEN active components under final operational conditions is reported.

9 pags., 6 figs., One of the factors that can contribute to the resolution of long, doped inorganic scintillators used for nuclear spectroscopy is the variation of the dopant concentration over the length the detector crystal. In this work an investigation of such potential variations in one of the CsI(Tl) scintillators used in the calorimeter, CALIFA, of the RB experiment at FAIR, has been performed using particle induced X-ray emission. No statistically significant gradient in doping level was found along the long axis of the investigated sample crystal and the mean value of the Tl concentration was measured to be 0.0839(38)% by weight. This corresponds to a light output of 97.3 % relative to the maximum attainable light output according to previously published work. By taking the ±1σ bounds, the 3% statistical spread in the relative light output provides a good reference value of the minimum light-output non-uniformity observed for the CALIFA crystals. If the relative light output is estimated pointwise from a set of Tl concentration measurements a light-output non-uniformity of 4.6(2.4)% results. For a γ-ray energy of 662 keV the deduced variation in Tl concentration contributes with 0.48(6)% to the typical resolution of 7.74(6)% measured with a collimated source along the crystal main axis. The result is of interest for the characterization of the detector system performance and for realistic simulations of the light collection process in detector systems that are used for nuclear spectroscopy and calorimetry., This work was supported by the Swedish research council (VR) grants 2017-03986, 2014-06644, 2013-04178, 2012-04550, BMBF contracts 05P15WOFNA, 05P19WOFN1, 05P15RDFN1, 05P19RDFN1, the TU Darmstadt – GSI cooperation contract HIC for FAIR, by the Spanish National Research Council, Spain grants FPA02015-64969-P (MINDECO/FEDER/EU), FPA2015-69640-C2-1-P, PGC2018-099746-B-C21, MDM-2016.0692 (MINECO/FEDER/EU) and by GRC, Germany ED431C 2017/54 (Xunta de Galicia/FEDER/EU).

Agradecimentos: This document was prepared by the LArIAT collaboration using the resources of the Fermi National Accelerator Laboratory (Fermilab), a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by Fermi Research Alliance, LLC (FRA), acting under Contract No. DE-AC02-07CH11359. We also gratefully acknowledge the support of the National Science Foundation; Brazil CNPq grant number 233511/2014-8, Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brazil (CAPES) -Finance Code 001, Sao Paulo Research Foundation -FAPESP (BR) grant number 16/22738-; Polish National Science Centre grant Dec2013/09/N/ST2/02793; the Science and Technology Facilities Council (STFC), part of the United Kingdom Research and Innovation; The Royal Society (United Kingdom); and the JSPS grant-in-aid (Grant Number 25105008), Japan. The collaboration extends a special thank you to the coordinators and technicians of the Fermilab Test Beam Facility, without whom none of this work would have been possible Abstract: The LArIAT liquid argon time projection chamber, placed in a tertiary beam of charged particles at the Fermilab Test Beam Facility, has collected large samples of pions, muons, electrons, protons, and kaons in the momentum range similar to 300-1400 MeV/c. This paper describes the main aspects of the detector and beamline, and also reports on calibrations performed for the detector and beamline components CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: This work was supported by MCTIC (Ministério da Ciência, Tecnologia, Inovações e Comunicações), supported by CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) and FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo). We thank also Dr. Andrzej Szelc, the UK-Latin America Program and the use of open facilities of Colab (CTI) Abstract: The photon detection system of the far detector of the Deep Underground Neutrino Experiment (DUNE) will collect liquid argon scintillation photons with an array of modules whose working principle is based on the ARAPUCA technology. These devices acting as light traps are able to convert VUV scintillation photons into visible ones and capture them inside a reflective cavity observed by an array of SiPMs as active photo-sensitive elements. The use of wavelength shifting techniques in light collecting systems for particle detection in liquid argon is of fundamental importance, since the scintillation photon wavelength is around 127 nm of the photon produced which is extremely challenging to be directly detected. The main objective of the present work was to explore and characterize different substrates, wavelength shifting compounds and deposition methods to optimize and improve the light collection of the ARAPUCA device CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: The authors would like to thank A. Hahn, R.P. Davis, W. Miner, K. Harding for their technical support at PAB. We also thank the whole Indiana University team with whom this experiment was performed. We also thank Eileen Hahn for her invaluable knowledge and support for the wavelength shifter coatings of filters and reflectors, and also Kenneth Treptow for his technical support in assembling the ARAPUCA's module. This work has been partially supported by the Brazilian agency FAPESP under grant no 2017/13942-5. Fermilab is Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy Abstract: In the Fall of 2017, two photon detector designs for the Deep Underground Neutrino Experiment (DUNE) Far Detector were installed and tested in the TallBo liquid argon (LAr) cryostat at the Proton Assembly (PAB) facility, Fermilab. The designs include two light bars developed at Indiana University and a photon detector based on the ARAPUCA light trap engineered by Colorado State University and Fermilab. The performance of these devices is determined by analyzing 8 weeks of cosmic ray data. The current paper focuses solely on the ARAPUCA device as the performance of the light bars will be reported separately. The paper briefly describes the ARAPUCA concept, the TallBo setup, and focuses on data analysis and results FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: The DarkSide collaboration would like to thank LNGS and its staff for invaluable technical and logistical support. This report is based upon work supported by the U.S. National Science Foundation (NSF) (Grants No. PHY-0919363, No. PHY-1004054, No. PHY-1004072, No. PHY1242585, No. PHY-1314483, No. PHY-1314507, associated collaborative grants, No. PHY1211308, No. PHY-1314501, No. PHY-1455351 and No. PHY-1606912, as well as Major Research Instrumentation Grant No. MRI-1429544), the Italian Istituto Nazionale di Fisica Nucleare (Grants from Italian Ministero dell'Istruzione, Universita, e Ricerca Progetto Premiale 2013 and Commissione Scientific Nazionale II). We acknowledge the financial support from the UnivEarthS Labex program of Sorbonne Paris Cite (Grants ANR-10-LABX-0023 and ANR-11-IDEX-000502), the Sao Paulo Research Foundation (Grant FAPESP-2016/09084-0), and the Russian Science Foundation Grant No. 16-12-10369. The authors were also supported by the "Unidad de Excelencia Maria de Maeztu: CIEMAT -Fisica de particulas" (Grant MDM2015-0509), the Polish National Science Centre (Grant No. UMO-2019/33/B/ST2/02884), the Foundation for Polish Science (Grant No. TEAM/2016-2/17), the International Research Agenda Programme AstroCeNT (Grant No. MAB/2018/7) funded by the Foundation for Polish Science from the European Regional Development Fund, the Science and Technology Facilities Council, part of the United Kingdom Research and Innovation, and The Royal Society (United Kingdom). We also wish to acknowledge the support from Pacific Northwest National Laboratory, which is operated by Battelle for the U.S. Department of Energy under Contract No. DE-AC05-76RL01830 Abstract: Large liquid argon detectors offer one of the best avenues for the detection of galactic weakly interacting massive particles (WIMPs) via their scattering on atomic nuclei. The liquid argon target allows exquisite discrimination between nuclear and electron recoil signals via pulse-shape discrimination of the scintillation signals. Atmospheric argon (AAr), however, has a naturally occurring radioactive isotope, Ar-39, a beta emitter of cosmogenic origin. For large detectors, the atmospheric Ar-39 activity poses pile-up concerns. The use of argon extracted from underground wells, deprived of Ar-39, is key to the physics potential of these experiments. The DarkSide-20k dark matter search experiment will operate a dual-phase time projection chamber with 50 tonnes of radio-pure underground argon (UAr), that was shown to be depleted of Ar-39 with respect to AAr by a factor larger than 1400. Assessing the Ar-39 content of the UAr during extraction is crucial for the success of DarkSide-20k, as well as for future experiments of the Global Argon Dark Matter Collaboration (GADMC). This will be carried out by the DArT in ArDM experiment, a small chamber made with extremely radio-pure materials that will be placed at the centre of the ArDM detector, in the Canfranc Underground Laboratory (LSC) in Spain. The ArDM LAr volume acts as an active veto for background radioactivity, mostly gamma-rays from the ArDM detector materials and the surrounding rock. This article describes the DArT in ArDM project, including the chamber design and construction, and reviews the background required to achieve the expected performance of the detector FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Aberto

Agradecimentos: This document was prepared by the LArIAT collaboration using the resources of Fermilab, a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by Fermi Research Alliance, LLC (FRA), acting under Contract No. DE-AC02-07CH11359. We extend a special thank you to the coordinators and technicians of the Fermilab Test Beam Facility, without whom this work would not have been possible. This work was directly supported by the National Science Foundation (NSF) through Grant No. PHY-1555090. We also gratefully acknowledge additional support from the NSF; Brazil CNPq Grant No. 233511/2014-8; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brazil (CAPES)—Finance Code 001; São Paulo Research Foundation—FAPESP (BR) Grant No. 16/22738-0; the Science and Technology Facilities Council (STFC), part of the United Kingdom Research and Innovation; The Royal Society (United Kingdom); the Polish National Science Centre Grant No. Dec-2013/09/N/ST2/02793; and the JSPS grant-in-aid (Grant No. 25105008), Japan Abstract: Precise calorimetric reconstruction of 5-50 MeV electrons in liquid argon time projection chambers (LArTPCs) will enable the study of astrophysical neutrinos in DUNE and could enhance the physics reach of oscillation analyses. Liquid argon scintillation light has the potential to improve energy reconstruction for low-energy electrons over charge-based measurements alone. Here we demonstrate light-augmented calorimetry for low-energy electrons in a single-phase LArTPC using a sample of Michel electrons from decays of stopping cosmic muons in the LArIAT experiment at Fermilab. Michel electron energy spectra are reconstructed using both a traditional charge-based approach as well as a more holistic approach that incorporates both charge and light. A maximum-likelihood fitter, using LArIAT's well-tuned simulation, is developed for combining these quantities to achieve optimal energy resolution. A sample of isolated electrons is simulated to better determine the energy resolution expected for astrophysical electron-neutrino charged-current interaction final states. In LArIAT, which has very low wire noise and an average light yield of 18 pe/MeV, an energy resolution of sigma/E similar or equal to 9.3%/root E circle plus 1.3% is achieved. Samples are then generated with varying wire noise levels and light yields to gauge the impact of light-augmented calorimetry in larger LArTPCs. At a charge-readout signal-to-noise of S/N similar or equal to 30, for example, the energy resolution for electrons below 40 MeV is improved by 10%, approximate to 120%, and approximate to 40% over charge-only calorimetry for average light yields of 10 pe/MeV, 20 pe/MeV, and 100 pe/MeV, respectively CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: The DarkSide Collaboration offers its profound gratitude to the LNGS and its staff for their invaluable technical and logistical support. We also thank the Fermilab Particle Physics, Scientific, and Core Computing Divisions. Construction and operation of the DarkSide-50 detector was supported by the U.S. National Science Foundation (NSF) (Grants No. PHY-0919363, No. PHY-1004072, No. PHY-1004054, No. PHY-1242585, No. PHY-1314483, No. PHY-1314501, No. PHY-1314507, No. PHY-1352795, No. PHY-1622415, and associated collaborative grants No. PHY-1211308 and No. PHY-1455351), the Italian Istituto Nazionale di Fisica Nucleare, the U.S. Department of Energy (Contracts No. DE-FG02-91ER40671, No. DEAC02-07CH11359, and No. DE-AC05-76RL01830), the Russian Science Foundation (Grant No. 18-72-00211), the Polish NCN (Grant No. UMO-2014/15/B/ST2/02561) and the Foundation for Polish Science (Grant No. Team2016-2/17). We also acknowledge financial support from the French Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), the UnivEarthS Labex program of Sorbonne Paris Cité (Grants No. ANR-10-LABX-0023 and No. ANR-11-IDEX-0005-02), and from the São Paulo Research Foundation (FAPESP) (Grant No. 2016/09084-0). Isotopes used in this research were supplied by the United States Department of Energy Office of Science by the Isotope Program in the Office of Nuclear Physics Abstract: We reanalyze data collected with the DarkSide-50 experiment and recently used to set limits on the spin-independent interaction rate of weakly interacting massive particles (WIMPs) on argon nuclei with an effective field theory framework. The dataset corresponds to a total (16660 +/- 270) kg d exposure using a target of low-radioactivity argon extracted from underground sources. We obtain upper limits on the effective couplings of the 12 leading operators in the nonrelativistic systematic expansion. For each effective coupling we set constraints on WIMP-nucleon cross sections, setting upper limits between 2.4 x 10(-45) cm(2) and 2.3 x 10(-42) cm(2) (8.9 x 10(-45) cm(2) and 6.0 x 10(-42) cm(2)) for WIMPs of mass of 100 GeV/c(2) (1000 GeV/c(2)) at 90% confidence level FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centres and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, PUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.). Individuals have received support from the Marie-Curie programme and the European Research Council and Horizon 2020 Grant, contract Nos. 675440, 752730, and 765710 (European Union); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie doorWeten-schap en Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the "Excellence of Science -EOS" -be.h project n. 30820817; the Beijing Municipal Science & Technology Commission, No. Z191100007219010; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Deutsche Forschungsgemeinschaft (DFG) under Germany's Excellence Strategy -EXC 2121 "Quantum Universe" -390833306; the Lendulet ("Momentum") Programme and the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences, the New National Excellence Program UNKP, the NKFIA research grants 123842, 123959, 124845, 124850, 125105, 128713, 128786, and 129058 (Hungary); the Council of Science and Industrial Research, India; the HOMING PLUS programme of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus programme of the Ministry of Science and Higher Education, the National Science Center (Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Research Program by QatarNational Research Fund; the Ministry of Science and Education, grant no. 14.W03.31.0026 (Russia); the Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias; the Thalis and Aristeia programmes cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); the Kavli Foundation; the Nvidia Corporation; the SuperMicro Corporation; the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.) Abstract: Measurements are presented of the reduction of signal output due to radiation damage for two types of plastic scintillator tiles used in the hadron endcap (HE) calorimeter of the CMS detector. The tiles were exposed to particles produced in proton-proton (pp) collisions at the CERN LHC with a center-of-mass energy of 13 TeV, corresponding to a delivered luminosity of 50 fb(-1) . The measurements are based on readout channels of the HE that were instrumented with silicon photomultipliers, and are derived using data from several sources: a laser calibration system, a movable radioactive source, as well as hadrons and muons produced in pp collisions. Results from several irradiation campaigns using Co-60 sources are also discussed. The damage is presented as a function of dose rate. Within the range of these measurements, for a fixed dose the damage increases with decreasing dose rate CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJ FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DO RIO GRANDE DO SUL - FAPERGS FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Aberto

In this article, a new method for the reconstruction of hit-position and hit-time of photons in long scintillator detectors is investigated. This article is motivated by the recent development of the positron emission tomography scanners based on plastic scintillators. The proposed method constitutes a new way of signal processing in multivoltage-technique. It is based on the determination of the degree of similarity between the registered signals and the synchronized model signals stored in a library. The library was established for a set of well-defined hit-positions along the length of the scintillator. The Mahalanobis distance was used as a measure of similarity between the two compared signals. The method was validated on the experimental data measured using two-strips J-PET prototype with dimensions of $5\times 9\times 300$ mm3. The obtained time-of-flight (TOF) and spatial resolutions amount to 325 ps (FWHM) and 25 mm (FWHM), respectively. The TOF resolution was also compared to the results of an analogous study done using the linear fitting method. The best TOF resolution was obtained with this method at four predefined threshold levels which was comparable to the resolution achieved from the Mahalanobis distance at two predefined threshold levels. Although the algorithm of the linear fitting method is much simpler to apply than the Mahalanobis method, the application of the Mahalanobis distance requires a lower number of applied threshold levels and, hence, decreases the costs of electronics used in PET scanner.

Agradecimentos: This document was prepared by the DUNE collaboration using the resources of the Fermi National Accelerator Laboratory (Fermilab), a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by Fermi Research Alliance, LLC (FRA), acting under Contract No. DE-AC02-07CH11359. This work was supported by CNPq, FAPERJ, FAPEG and FAPESP, Brazil; CFI, IPP and NSERC, Canada; CERN; MŠMT, Czech Republic; ERDF, H2020-EU and MSCA, European Union; CNRS/IN2P3 and CEA, France; INFN, Italy; FCT, Portugal; NRF, South Korea; CAM, Fundación "La Caixa" and MICINN, Spain; SERI and SNSF, Switzerland; TÜBITAK, Turkey; The Royal Society and UKRI/STFC, UK; DOE and NSF, United States of America. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231 Abstract: The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE will resolve the neutrino mass ordering to a precision of 5 sigma, for all delta CP values, after 2 years of running with the nominal detector design and beam configuration. It has the potential to observe charge-parity violation in the neutrino sector to a precision of 3 sigma (5 sigma) after an exposure of 5 (10) years, for 50% of all delta CP values. It will also make precise measurements of other parameters governing long-baseline neutrino oscillation, and after an exposure of 15 years will achieve a similar sensitivity to sin22 theta 13 to current reactor experiments CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJ FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁS - FAPEG FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO Aberto