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Experiments with antiprotons often require the tracking of charged particles emerging from the annihilation process. The Atomic Spectroscopy And Collisions Using Slow Antiprotons (ASACUSA) collaboration at the CERN Antiproton Decelerator (AD) used several panels of scintillating bars placed around the interaction region to detect the passage of charged pions and determine the annihilation vertex position and time. The panels were composed by extruded scintillating bars and the light was collected using WaveLength Shifting (WLS) fibers and multi-anode PhotoMultiplier Tubes (PMTs). After operating for several years, the fiber-PMT coupling quality had degraded and a major upgrade of the light readout system was planned. The PMTs will be replaced by Silicon PhotoMultipliers (SiPMs) and the front-end electronics changed accordingly. An improvement is expected in the efficiency and the uniformity of the detector response. In this contribution the commissioning of the upgrade will be described, including the results of preliminary tests with cosmic rays. [ABSTRACT FROM AUTHOR]

MALTA is part of the Depleted Monolithic Active Pixel sensors designed in Tower 180 nm CMOS imaging technology. A custom telescope with six MALTA planes has been developed for test beam campaigns at SPS, CERN, with the ability to host several devices under test. The telescope system has a dedicated custom readout, online monitoring integrated into DAQ with realtime hit map, time distribution and event hit multiplicity. It hosts a dedicated fully configurable trigger system enabling to trigger on coincidence between telescope planes and timing reference from a scintillator. The excellent time resolution performance allows for fast track reconstruction, due to the possibility to retain a low hit multiplicity per event which reduces the combinatorics. This paper reviews the architecture of the system and its performance during the 2021 and 2022 test beam campaign at the SPS North Area. [ABSTRACT FROM AUTHOR]

Scintillation crystals Gd3Al2Ga3O12 (GAGG) are an excellent candidate for application in ionizing-radiation detectors because of their high radiation resistance, density and light yield. These crystals can be used in combination with lead tungstate (PbWO4 or PWO) crystals for the development of a new generation of electromagnetic calorimeter with advanced spatial and energy resolutions in a broad energy range. PWO crystals enable the accurate detection of high-energy photons, while GAGG crystals provide the possibility of precisely measuring photon energies, down to a few MeV. Different options for a composite electromagnetic calorimeter based on PWO and GAGG crystals are considered to optimize spatial and energy resolutions in a broad energy range (from 1 MeV to 100 GeV). In particular, different lengths of the GAGG section of the calorimeter are considered, from 0.5 to 10 cm. The separation of signals from photons and hadrons is also taken into consideration through the study of shower shape in the calorimeter. The optimization is based on Geant4 simulations, considering light collection as well as the use of different photodetectors and electronic noise. Simulations are verified with light yield measurements of GAGG samples obtained using radioactive sources and test beam measurements of the prototype of the PWO-based Photon Spectrometer of the ALICE experiment at CERN. [ABSTRACT FROM AUTHOR]

Scintillation crystals Gd Al Ga O (GAGG) are considered for the application in ionizing-radiation detectors because of their high radiation resistance, density and light yield. These crystals can be used in addition to lead tungstate (PbWO or PWO) crystals for the development of a new generation electromagnetic calorimeter with good spatial and energy resolutions in a broad energy range. PWO crystals enable an accurate detection of high energy photons, while the addition of GAGG crystals makes it possible to precisely measure photon energies down to a few MeV units. Different options of composite electromagnetic calorimeter based on PWO and GAGG crystals are considered to optimize spatial and energy resolutions in a broad energy range (from 1 MeV to 100 GeV). The optimization is based on Geant4 simulations taking into account light collection as well as using different photodetectors and noise of electronics. The simulations are verified with the help of light yield measurements of GAGG samples obtained using radioactive sources and test beam measurements of PWO based photon spectrometer of the ALICE experiment at CERN. [ABSTRACT FROM AUTHOR]

This article presents a few selected developments and future ideas related to the measurement of (n , γ) data of astrophysical interest at CERN n_TOF. The MC-aided analysis methodology for the use of low-efficiency radiation detectors in time-of-flight neutron-capture measurements is discussed, with particular emphasis on the systematic accuracy. Several recent instrumental advances are also presented, such as the development of total-energy detectors with γ -ray imaging capability for background suppression, and the development of an array of small-volume organic scintillators aimed at exploiting the high instantaneous neutron-flux of EAR2. Finally, astrophysics prospects related to the intermediate i neutron-capture process of nucleosynthesis are discussed in the context of the new NEAR activation area. [ABSTRACT FROM AUTHOR]

A new fibre-sampling dual-readout calorimeter prototype has been qualified on beam at two facilities (DESY and CERN) using electrons from 1 to 100 GeV. The prototype was designed to almost fully contain electromagnetic showers and a central module (highly granular readout) was equipped with 320 Silicon Photomultipliers (SiPMs) spaced by 2 mm and individually read out. The test beams performed in 2021, allowed to qualify the readout boards used to operate the SiPMs, to define the calibration procedure and to measure the light yield for scintillating and Cherenkov signals produced by the shower development. This paper reports the first results obtained with the highly granular readout and discusses the ongoing R&D to address some open questions concerning the mechanical integration and the scalable readout scheme that will allow to build and operate the next prototype designed for hadronic showers containment. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

FASER, or the Forward Search Experiment, is a new experiment at CERN designed to complement the LHC's ongoing physics program, extending its discovery potential to light and weakly interacting particles that may be produced copiously at the LHC in the far-forward region. New particles targeted by FASER, such as long-lived dark photons or axion-like particles, are characterised by a signature with two oppositely charged tracks or two photons in the multi-TeV range that emanate from a common vertex inside the detector. The full detector was successfully installed in March 2021 in an LHC side tunnel 480 m downstream from the interaction point in the ATLAS detector. FASER is planned to be operational for LHC Run 3. The experiment is composed of a silicon-strip tracking-based spectrometer using three dipole magnets with a 20 cm aperture, supplemented by four scintillator stations and an electromagnetic calorimeter. The FASER electromagnetic calorimeter is constructed from four spare LHCb calorimeter modules. The modules are of the Shashlik type with interleaved scintillator and lead plates that result in 25 radiation lengths and 1% energy resolution for TeV electromagnetic showers. In 2021, a test beam campaign was carried out using one of the CERN SPS beam lines to set up the calibration of the FASER calorimeter system in preparation for physics data taking. The relative calorimeter response to electrons with energies between 10 and 300 GeV, as well as high energy muons and pions, has been measured under various high voltage settings and beam positions. The measured calorimeter resolution, energy calibration, and particle identification capabilities are presented. [ABSTRACT FROM AUTHOR]

Because of their potential low cost, bright light, and fast decay time, LuAG:Ce ceramic scintillators have attracted a broad interest in the high-energy physics community. One crucial issue for their application in future high-energy physics experiments is their radiation hardness against neutrons and protons expected at future hadron colliders. We report optical and scintillation performance of 1-mm LuAG:Ce ceramic samples doped with Mg2+ (and Ca2+) and their radiation damage induced by hadrons. While Mg2+ co-doping improves their light output, Ca2+ co-doping improves their fast to total (F/T) ratio. LuAG:Ce ceramic samples were irradiated at the Los Alamos Neutron Science Center (LANSCE), Los Alamos, NM, USA, by neutrons up to $6.7\times 10^{15}\,\,\text{n}_{\mathrm {eq}}$ /cm2 and by 24-GeV and 800-MeV protons at CERN PS-IRRAD up to $1.2\times 10^{15}$ p/cm2 and at LANSCE up to $2.3\times 10^{14}$ p/cm2, respectively. All samples show excellent radiation hardness with more than 90% of light after irradiation. The RIAC values induced by neutrons are found to be a factor of 2 smaller than lutetium–yttrium oxyorthosilicate (LYSO:Ce) crystals. The RIAC values induced by protons are also found a factor of 2 smaller than LYSO:Ce crystals in LuAG:Ce ceramic samples with good optical quality. Research and development will continue to develop LuAG:Ce scintillating ceramics with improved optical quality for future investigation. [ABSTRACT FROM AUTHOR]

The advent of the silicon photomultiplier has allowed the development of highly segmented calorimeters using plastic scintillator as the active media, with photodetectors embedded in the calorimeter, in dimples in the plastic. To reduce the photodetector's dark current and radiation damage, the high granularity calorimeter designed for the high luminosity upgrade of the CMS detector at CERN's Large Hadron Collider will be operated at a temperature of about −30 °C. Due to flammability considerations, a low oxygen environment is being considered. However, the radiation damage to the plastic scintillator during irradiation in this operating environment needs to be considered. In this paper, we present measurements of the relative decrease of light output during irradiation of small plastic scintillator tiles read out by silicon photomultipliers. The irradiations were performed using a 60 Co source both to produce the tiles' light and as a source of ionizing irradiation at dose rates of 0.3, 1.3, and 1.6 Gy/h, temperatures of −30, −15, −5, and 0 °C, and with several different oxygen concentrations in the surrounding atmosphere. The effect of the material used to wrap the tile was also studied. Substantial temporary damage, which annealed when the sample was warmed, was seen during the low-temperature irradiations, regardless of the oxygen concentration and wrapping material. The relative light loss was largest with 3MTM Enhanced Specular Reflector Film wrapping and smallest with no wrapping, although due to the substantially higher light yield with wrapping, the final light output is largest with wrapping. The light loss was less at warmer temperatures. Damage with 3% oxygen was similar to that in standard atmosphere. Evidence of a plateau in the radical density was seen for the 0 °C data. [ABSTRACT FROM AUTHOR]

A project of the OLVE-HERO space detector for measurement of the cosmic rays in the range 1012–1016 eV is proposed. It will include a large ionization-neutron 3D calorimeter with a high granularity and geometric factor of ∼16 m2 sr. The main OLVE-HERO detector is expected to be an image calorimeter with boron loaded plastic scintillator and a tungsten absorber. Such a calorimeter allows to measure an additional neutron signal that should improve the detector energy resolution and also the rejection power between electromagnetic and nuclear components of cosmic rays. Improvement by factor 30–50 is expected. The OLVE-HERO detector prototype was designed and tested at SPS CERN beam during Pb ion run in 2018. Test results and the corresponding Monte-Carlo simulation are presented. [ABSTRACT FROM AUTHOR]

CERN Radiation Protection group has recently developed a novel radiation survey meter called B-RAD able to operate in the presence of a strong magnetic field. The B-RAD will be equipped with a series of probes for gamma dose rate, gamma spectrometry and surface contamination measurements. The feasibility of developing a probe for neutron dose rate and possibly spectral measurements is being investigated. The determination of the breakdown voltage of the SiPM as well as its uniformity between the pixels was performed. The energy resolution of the Cs2LiYCl6:Ce (CLYC) scintillator was measured with the SiPM and compared with two different PMT models: Bialkali and Superbialkali. The temperature sensitivity of the system CLYC + SiPM was measured from −10 to + 40°C. [ABSTRACT FROM AUTHOR]

Future satellite experiments for cosmic-ray and gamma-ray detection will employ plastic scintillators to discriminate gamma-rays from charged particles and to identify nuclei up to Iron. The High Energy Cosmic Radiation Detector (HERD) facility will be one of those new experiments and it will be installed onboard the Chinese Tiangong Space Station (TSS). The main goal of the HERD experiment is to detect charged cosmic-rays up to PeV and gamma-rays up to hundred GeV s. The plastic scintillator detector (PSD) surrounds the inner detectors on five sides. For energies above a few GeV s a high detector segmentation is required in order to avoid the back-splash effect, due to the interaction between high energy particles and the innermost calorimeter. Each PSD basic element (bar or tile) is coupled to several Silicon Photomultipliers (SiPMs) for the detection of scintillation light. In 2021 we have performed a beam test campaign to test all the subdetectors of the HERD experiment at CERN PS and SPS. We tested two different PSD prototypes, one with a long bar geometry and the other with a squared tile geometry. In both prototypes two scintillating materials (BC-404 and BC-408) were used. Both the prototypes were equipped with SiPMs of two different sizes (MPPC S14160-3050 and S14160-1315) and they were read-out by the CAEN Citiroc-based board DT5550 W. In this work we will describe the PSD design along with the beam test results. [ABSTRACT FROM AUTHOR]

Abstract The TileCal section of the hadronic calorimeter of the ATLAS detector at the Large Hadron Collider (LHC), CERN, is a sampling calorimeter employing steel plates as absorber and plastic scintillator tiles read out by photomultiplier tubes (PMTs) as the active medium. We present an overview of the calibration system that enables the TileCal to meet its design goals of sub-1% level accuracy as well as excellent short- and long-term stability through constant monitoring. [ABSTRACT FROM AUTHOR]

In this study, the possibility of on-line monitoring of an ultra-high-energy (UHE) beam of 150 GeV/n lead (208Pb) ions using a liquid-filled ionization chamber array (OCTAVIUS 1000SRS, PTW Freiburg, Germany) is evaluated. The applicability of the array has been tested for the investigated beam, where adequate adjustments of the array have been made for measurements under very low fluxes of 102 to 104 ions / cm 2 /s. The results have been compared to measurements obtained using the standard beam line detectors, such as a scintillator and a delay wire chamber (DWC). Since these detectors were situated further upstream from the experimental position, measurements with these devices may not be representative of the beam characteristics at setup due to the interactions of the primary beam particles within these detectors and the subsequent transport of these particles between these detectors and the setup. The main advantage of the application of the liquid-filled array is its portability so that it can be placed directly at the position of the experimental setup to capture the beam characteristics. A comparison between the measured beam profile and independent film measurements has demonstrated its reliability for analysing the beam characteristics. In this context, the 2D array has been implemented to measure on-line not only the 2D beam profile but also the total imparting particle fluence of the UHE lead beam by using the measured dose and considering the calibration of the detector. [ABSTRACT FROM AUTHOR]

A tracking detector composed of scintillator bars with a triangular cross-section read out by silicon photomultipliers in analog mode was developed. The tracker was designed to instrument a low density spectrometer for neutrino experiments. The performance of the system has been studied by exposing it to charged particle beams at the CERN-PS. The tests have shown that the position resolution in reconstructing charged particles' tracks is within 2.2 mm over the momentum range 0.5–10 GeV/c. [ABSTRACT FROM AUTHOR]

The long baseline neutrino experiment T2K has launched the upgrade project of its near detector ND280, crucial to reduce the systematic uncertainties in the prediction of number of events at the far detector to less than 4 %. An essential component of this upgrade is a highly segmented scintillator detector, acting as a fully active target for neutrino interactions, called SuperFGD, with dimensions of 192 × 192 × 56 cm3 a total mass of about 2 tonnes. Prototypes of this detector have been tested in a beam of charged particles at CERN in 2017 and 2018. The detector response, including the light yield and the time resolution are presented. The installation of new components for the upgrade of ND280 is planned in 2021. • The SuperFGD design features are presented. • The results from a SuperFGD prototype at the CERN beam tests are shown. • High detection efficiencies for MIPs with a LY of 50 [p.e.] per readout view. • Wide dynamics range to fully characterize stopping protons (LY ∼ 500 [p.e.]). • Time resolution for the MIP hits is found to be ∼ 0.9 ns. [ABSTRACT FROM AUTHOR]

The CMS experiment at CERN will undergo significant improvements during the Phase-II Upgrade to operate with a 10-fold increase in luminosity and the associated event pileup of the High Luminosity LHC (HL-LHC). The forward calorimetry will be exposed to very high radiation levels and the CMS collaboration is designing a new calorimeter, the High Granularity Calorimeter (CE), to replace the existing endcap calorimeters. It will have higher transverse and longitudinal segmentation for both electromagnetic (CE-E) and hadronic (CE-H) sections to facilitate particle-flow reconstruction. The fine structure of showers can be measured and used to enhance particle identification, whilst still achieving good energy resolution. The CE-E, and a large fraction of CE-H, will be based on hexagonal silicon sensors produced from 8-inch wafers, each with several hundreds of individual cells of 0.5 – 1 cm2 cell size. The remainder of the CE-H will be based on highly-segmented scintillators read out with SiPMs. The overview of the CE project presented in this paper is focused on the silicon sensors covering motivation, engineering design, expected performance and the current status of prototypes, from lab measurements to beam tests. [ABSTRACT FROM AUTHOR]

The CMS detector at the CERN Large Hadron Collider is undergoing an extensive Phase II upgrade programme to prepare for the challenging conditions of the High-Luminosity LHC. In particular, a new timing detector, the MTD, will measure minimum ionizing particles with a time resolution of 30–50 ps and hermetic coverage up to a pseudo-rapidity of | η | = 3. The MTD will consist of a central barrel region based on L(Y)SO:Ce crystals read out with SiPMs and two end-caps instrumented with radiation-tolerant low gain avalanche detectors. The precision time information from the MTD will reduce the effects of the high levels of pile-up expected at the High-Luminosity LHC and will bring new and unique capabilities to the CMS detector. The time information assigned to each track will enable the use of 4D reconstruction algorithms and will further discriminate interaction vertices within the same bunch crossing to recover the track purity of vertices in current LHC conditions. We present the motivations for precision timing at the High-Luminosity LHC, the overall detector design and technological choices including ongoing R&D studies targeting enhanced timing performance and radiation tolerance. [ABSTRACT FROM AUTHOR]

We present the first application of polysiloxane-based scintillators as active medium in a shashlik sampling calorimeter. These results were obtained from a testbeam campaign of a ∼ 6 × 6 × 45 cm 3 (13 X 0 depth) prototype. A Wavelength Shifting fiber array of 36 elements runs perpendicularly to the stack of iron (15 mm) and polysiloxane scintillator (15 mm) tiles with a density of about one over cm 2. Unlike shashlik calorimeters based on plastic organic scintillators, here fibers are optically matched with the scintillator without any intermediate air gap. The prototype features a compact light readout based on Silicon Photo-Multipliers embedded in the bulk of the detector. The detector was tested with electrons, pions and muons with energies ranging from 1 to 7 GeV at the CERN-PS. This solution offers a highly radiation hard detector to instrument the decay region of a neutrino beam, providing an event-by-event measurement of high-angle decay products associated with neutrino production (ENUBET, Enhanced NeUtrino BEams from kaon Tagging, ERC project). The results in terms of light yield, uniformity and energy resolution, are compared to a similar calorimeter built with ordinary plastic scintillators. [ABSTRACT FROM AUTHOR]

Being the first astronomical scientific satellite of China, Dark Matter Particle Explorer (DAMPE) has been launched on D e c. 17 , 2015. One of scientific objects of DAMPE is studying the acceleration and propagation mechanisms of cosmic rays by measuring the flux of nuclei cosmic rays up to several hundred T e V s. As one of the key detectors of DAMPE, the Plastics Scintillator Detector (PSD) is used for the nuclei identification as well for the photons/electrons separation. After assembly of DAMPE engineering qualified model (EQM), several beam tests were conducted at CERN to study the performance and the reliability of DAMPE. In this paper, design verification and performance of PSD with heavy ion beam tests will be reported in detail. [ABSTRACT FROM AUTHOR]

The 14th International Conference on Inorganic Scintillators and Their Applications (SCINT 2017) was organized by CERN, and held on September 17–22, 2017, in Chamonix, France. This was a particular event in the series of SCINT conferences, since we celebrated the 25th anniversary of its birth in 1992. Intentionally, it has also been held at the place of its origin. The conference was dedicated to the late Marvin Weber, one of the fathers of scintillator research. The 273 colleagues from 35 different countries finally participated at the conference. The scientific program was introduced by a memorial lecture about 25 years of history of the SCINT conference given by Bill Moses. The program consisted of nine invited lectures, and 79 oral and 119 poster contributions. As a part of the program, one session was devoted to an Industrial Event organized by the COST Action TD1401 with two invited lectures, presentation of six companies, and a round table discussion at the end. Extended exhibition with altogether 18 exhibitor stands provided another link to the market applications behind the research. An intense and structured research and development in this field was represented by 13 sessions oriented toward various material technologies including nanomaterials, metamaterials, classical bulk single crystals, and optical ceramics. Their characterization, modeling, and underlying physical mechanisms constituted the subject of major part of conference contributions. Finally, also various applications of inorganic scintillators were presented and discussed. [ABSTRACT FROM AUTHOR]