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The DArk Matter Particle Explorer (DAMPE) is a satellite-borne, calorimetric-type, high-energy-resolution detector for the precise measurement of high-energy electrons, gamma rays, and nuclei from deep space. The DAMPE electromagnetic calorimeter consists of bismuth germanate (BGO) crystals that can measure incident hadron energies from 50 GeV to 100 TeV. For an inorganic scintillator, such as BGO, the nonlinear fluorescence response when measuring ions contributes to the difference between the experimental data and Monte Carlo simulations. This article reports the BGO quenching nonlinearity occurring in the DAMPE experiment. The ionization energy response of BGO to several kinds of ions lighter than iron is investigated by conducting beam tests and analyzing flight data. We compare the scintillator output with the energy loss according to GEANT4 simulations and determine the quenching parameters. The combined result of beam test and flight experiment shows that the quenching effect strongly depends on the density of the ionization energy loss. [ABSTRACT FROM AUTHOR]

In this paper, the goals and scientific tasks of the space experiment "High Energy Rays Observatory" (HERO) are established. The preliminary design of the scientific equipment is presented, the characteristic features of which are its high geometric factor (up to ∼20 m2 sr) and adequate energy measurement resolution (20–30% or better, depending on the type of components). The ionisation tungsten-scintillator calorimeter is used for energy measurement. The total calorimeter weight is equal to 12 tons. The technical characteristics of the equipment permit the direct study of cosmic rays in a wide energy range, including the unexplored region of 1015–1016 eV. The current status of the space experiment is discussed. Currently, the HERO project is in its pre-R&D phase. The launch of the satellite is planned for between 2025 and 2030. [ABSTRACT FROM AUTHOR]

Abstract An antihydrogen detector consisting of a thin BGO disk and a surrounding plastic scintillator hodoscope has been developed. We have characterized the two-dimensional positions sensitivity of the thin BGO disk and energy deposition into the BGO was calibrated using cosmic rays by comparing experimental data with Monte-Carlo simulations. The particle tracks were defined by connecting BGO hit positions and hits on the surrounding hodoscope scintillator bars. The event rate was investigated as a function of the angles between the tracks and the energy deposition in the BGO for simulated antiproton events, and for measured and simulated cosmic ray events. Identification of the antihydrogen Monte Carlo events was performed using the energy deposited in the BGO and the particle tracks. The cosmic ray background was limited to 12 mHz with a detection efficiency of 81%. The signal-to-noise ratio was improved from 0.22 s − 1 ∕ 2 obtained with the detector in 2012 to 0.26 s − 1 ∕ 2 in this work. [ABSTRACT FROM AUTHOR]

Particle detectors based on scintillation light are particularly well suited for precision timing applications with resolutions of a few 10’s of ps. The large primary signal and the initial rise time of the scintillation light result in very favorable signal-to-noise conditions with fast signals. In this paper we describe timing studies using a LYSO-based sampling calorimeter with wavelength-shifting capillary light extraction and silicon photomultipliers as photosensors. We study the contributions of various steps of the signal generation to the total time resolution, and demonstrate its feasibility as a radiation-hard technology for calorimeters at high intensity hadron colliders. [ABSTRACT FROM AUTHOR]

The direct detection of high-energy cosmic rays up to the PeV region is one of the major challenges for the next generation of space-borne cosmic-ray detectors. The physics performance will be primarily determined by their geometrical acceptance and energy resolution. CaloCube is a homogeneous calorimeter whose geometry allows an almost isotropic response, so as to detect particles arriving from every direction in space, thus maximizing the acceptance. A comparative study of different scintillating materials and mechanical structures has been performed by means of Monte Carlo simulation. The scintillation-Cherenkov dual read-out technique has been also considered and its benefit evaluated. [ABSTRACT FROM AUTHOR]

SuperNEMO is a double- β decay experiment, which will employ the successful tracker–calorimeter technique used in the recently completed NEMO-3 experiment. SuperNEMO will implement 100 kg of double- β decay isotope, reaching a sensitivity to the neutrinoless double- β decay ( 0 ν β β ) half-life of the order of 1 0 26 yr, corresponding to a Majorana neutrino mass of 50–100 meV. One of the main goals and challenges of the SuperNEMO detector development programme has been to reach a calorimeter energy resolution, Δ E ∕ E , around 3 % ∕ E ( MeV ) σ , or 7 % ∕ E ( MeV ) FWHM (full width at half maximum), using a calorimeter composed of large volume plastic scintillator blocks coupled to photomultiplier tubes. We describe the R&D programme and the final design of the SuperNEMO calorimeter that has met this challenging goal. [ABSTRACT FROM AUTHOR]

In this work heavy bismuth-borate glasses were studied as host matrices of Dy 2 O 3 rare earth, for potential application as scintillator materials in high energy physics experiments and in general radiation detection systems. Glass matrices were prepared from 20BaO-xBi 2 O 3 -(80-x)B 2 O 3 (x = 20, 30, 40 mol%) ternary systems and synthesized by the melt-quenching method at different temperatures in order to obtain high density and high transparency in the UV/Vis range. Particularly, the glass manifesting the higher transparency and with sufficiently high density was doped with Dy 2 O 3 (2.5 and 5 mol%) in order to induce the luminescence characteristics. The effects of Bi 2 O 3 and Dy 2 O 3 on density, thermal behaviour, transmission as well as luminescence properties under UV excitation, were investigated. The experimental results show that the synthesized glasses can be considered promising candidate materials as dense scintillators, due to the Dy 3 + centres emission. [ABSTRACT FROM AUTHOR]

Several future Higgs factories are planned for the precision Higgs physics to search for the new physics. The highly granular calorimeters play a crucial role on the precision Higgs measurement. The highly granular Sc-ECAL is based on a scintillator strip readout by a SiPM to realize the 5 mm × 5 mm cell size by aligning the strips orthogonally in x–y configuration. In order to demonstrate the performance of the Sc-ECAL and the scalability to the full-scale detector, the technological prototype has been developed with full 30 layers. The per-channel calibrations and performance demonstration are successfully done by the long-term commissioning tests with LED and cosmic-ray. This article describes the results of the commissioning tests where excellent performance of the prototype has been successfully demonstrated. [ABSTRACT FROM AUTHOR]

The Calorimeter of the Mu2e experiment is a complicated detector made of crystal scintillators with dedicated read-out electronics per crystals. The compactness of the Front-End Units matrix, the complexity of the necessary services, and the limited space available after detector installation in the experimental hall make access, manipulation and maintenance of the Front-End Units very hard. This paper reports on the conceptual mechanical design of a robotic arm composed of a gantry structure for x y z positioning on the desired Front-End Unit and equipped with custom-designed grippers to perform the necessary maintenance operations. This includes the optimization of the Front-End Units cables routing. [ABSTRACT FROM AUTHOR]

The MEG II experiment is searching for new physics beyond the SM (e.g. SUSY-GUT, SUSY-seesaw) through the lepton flavor violating μ + → e + γ decay with ten times better sensitivity than the MEG experiment. The MEG collaboration published the result of B (μ + → e + γ) < 4. 2 × 1 0 − 13 at 90% C.L. in 2016, which was thirty times better result than the previous limit. As the sensitivity of the MEG experiment was already limited by the accidental background, the MEG detector had to be upgraded to reach one order of magnitude better sensitivity. The MEG experiment utilized 846 2 inch PMTs to detect scintillation light in a 900 l liquid xenon γ calorimeter. In the MEG II experiment, 216 2 inch PMTs on the γ incident face were replaced with 4092 MPPCs (SiPMs produced by Hamamatsu) to improve the energy and position resolutions. We started the detector commissioning with the full electronics readout channels for the first time in 2021, and soon after, we started the physics data taking. Here the LXe detector status including initial photon sensor calibration and performance will be summarized together with the expected detector performance. The PDE decrease of the SiPM observed in the high rate muon beam environment and our possible remedy will also be discussed. [ABSTRACT FROM AUTHOR]

We describe an algorithm which has been developed to extract fine granularity information from an electromagnetic calorimeter (ECAL) with strip-based readout. Such a calorimeter, based on scintillator strips, is being developed to apply particle flow reconstruction to future experiments in high energy physics. The application of this algorithm to 100 GeV hadronic jets in an ECAL with 45×5 mm 2 transverse segmentation improves the energy resolution from 3.6% to 3.0%, to be compared to the resolution of 2.9% achieved by an ECAL with 5×5 mm 2 segmentation. The performance can be further improved by the use of 10×10 mm 2 tile-shaped layers interspersed between strip layers. [ABSTRACT FROM AUTHOR]

Large area Silicon PhotoMultipliers (SiPMs) are the new frontier of the development of readout systems for scintillating detectors. A SiPM consists of a matrix of parallel-connected silicon micropixels operating in limited Geiger–Muller avalanche mode, and thus working as independent photon counters with a very high gain (~10 6 ). This contribution presents the performance in terms of linearity and energy resolution of an electromagnetic homogeneous calorimeter composed of 9 ~ 18 X 0 LYSO crystals. The crystals were readout by 36 4×4 mm 2 SiPMs (4 for each crystal) produced by FBK-irst. This calorimeter was tested at the Beam Test Facility at the INFN laboratories in Frascati with a single- and multi-particle electron beam in the 100–500 MeV energy range. [ABSTRACT FROM AUTHOR]

A sampling calorimeter using cerium fluoride scintillating crystals as active material, interleaved with absorber plates made of tungsten, and read out by wavelength-shifting fibres has been tested with high-energy electron beams at the CERN SPS H4 beam line, as well as with lower-energy beams at the INFN Frascati Beam Test Facility in Italy. Energy resolution studies revealed a low stochastic term ( < 10 % / E ) . This result, combined with high radiation hardness of the material used, marks this sampling calorimeter as a good candidate for the detectors׳ forward regions during the high luminosity phase of LHC. [ABSTRACT FROM AUTHOR]

Performance parameters of a composite detection module of Spaghetti type Calorimeter (SPACAL), which is considered for the inner part of the future LHCb Electromagnetic Calorimeter (ECAL) in Upgrade Phase 2, are simulated using GEANT4 software supported by analytical calculations. The accuracy of the timestamp is estimated in both the front and back sections of the composite detector, whereas the energy resolution is estimated for the total signal from the front and back sections of the detector. The rise time of the scintillation response used in the calculations is reconstructed using the results of the coincidence time resolution measurements with annihilation γ -quanta. The time and energy resolutions with PMT readout are compared for Ce-doped garnet- and oxyorthosilicate-type single crystal scintillators without codoping and codoped with aliovalent impurities. [ABSTRACT FROM AUTHOR]

The scintillator tiles with direct readout by silicon photomultipliers (SiPM) have been studied. The SiPM is placed inside the dimple machined in the center of the big face of 30×30×3 mm 3 tile. The different dimple geometries were studied. The tiles with the optimal dimple design show the uniformity of response comparable to the tiles with fiber readout. The direct-readout approach provides a reasonable way for the construction of supermultichannel calorimeters. [ABSTRACT FROM AUTHOR]

The challenges for new calorimetry for incoming experiments at the intensity frontier is to provide detectors with ultra-precise time resolution and supreme energy resolution. Two very promising materials on the market are BrilLanCe (Cerium doped Lanthanum Bromide LaBr 3 (Ce)) and LYSO (Lutetium Yttrium OxyorthoSilicate, Lu 2 (1 − x) Y 2 x SiO 5 (Ce)), supported by recent developments aiming at providing relatively large crystals. The response of LaBr 3 (Ce) and LYSO prototypes fired with gammas at an energy of 55 MeV have been studied. Very promising results were obtained. For the newly available (radius R = 4.45 cm, length L = 20.32 cm) LaBr 3 (Ce) crystal an energy resolution of σ E ∕ E ≈ 2.36(8) % and a timing resolution of σ t = 35(1) ps have been predicted. The energy resolution can be further improved by using larger crystals (either R = 6.35 cm or R = 7.62 cm, L = 20.32 cm) approaching respectively a σ E ∕ E = 1.20(3) % or a σ E ∕ E = 0.91(1) %. Due to the shorter radiation length X 0 and smaller Molière radius (R M) a LYSO crystal of the available size (radius R = 3.5 cm, L = 16 cm) performs better in terms of energy deposit compared to the currently available larger crystal made of LaBr3(Ce). An energy resolution of σ E ∕ E = 1.48(4) % can be obtained, further improved by using bigger crystals (R = 6.5 cm, L = 25 cm) to σ E ∕ E = 0.74(1) %. A timing resolution less performing than the LaBr 3 (Ce) but better than any nowadays available calorimeter working at this energy can be achieved and is expected to be σ t = 49(1) ps. Such results put these materials coupled to silicon photomultipliers at the detector forefront for future high energy calorimetry at the intensity frontier. [ABSTRACT FROM AUTHOR]

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

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]

Neutrino cross-section measurements are an essential requirement for the next generation of neutrino oscillation experiments and they are presently limited by uncertainties on neutrino fluxes. In [1] we propose to instrument a neutrino decay tunnel to detect large angle positrons and tag the three-body semileptonic K + → e + π 0 ν e decays. In such a facility the absolute electron neutrino flux could be determined with unprecedented precision (O(1%)). An e + /π + separation capability of about 2% as well as a high e + efficiency is required for a diffuse particle source over a length of several tens of meters. Additional constraints, due to the harsh beam environment, involve radiation hardness and fast response. For this purpose we propose a specialized shashlik calorimeter (copper-scintillator) with a compact readout based on small-area Silicon PhotoMultipliers coupled to WLS fibers. The setup would allow an effective longitudinal segmentation for electron/hadron separation, reducing the dead zones introduced by fiber bundling. Detailed Monte Carlo simulations are in progress. The construction of a small prototype and exposures to pion and electron beams are foreseen. [ABSTRACT FROM AUTHOR]