The current status of the R&D performed for the ePIC-dRICH detector at the EIC is presented. A special focus will be given to the beam test results obtained with the dRICH prototype SiPM optical readout. A large-area readout plane consisting of a total of 1280 3 x3 mm2 2 SiPM sensors was built and tested with particle beams at CERN-PS in October 2023. The modular photodetector is based on a novel EIC-driven prototype photodetection unit (PDU) developed by INFN, which integrates 256 SiPM pixel sensors, cooling and TDC electronics in a volume of roughly 5x5x 14 cm3. 3 . The data have been collected with a complete chain of front-end and readout electronics based on the ALCOR chip, developed by INFN Torino. The features of the PDU and the performance of the full dRICH SiPM prototype system will be highlighted.

A dual-radiator Ring Imaging Cherenkov (dRICH) will provide charged hadrons particle identification in the hadronic end-cap of a general-purpose experiment at the future Electron–Ion Collider (EIC). We developed a prototype to test the performance and validate the use of Silicon Photo-Multipliers (SiPM), the baseline photo-sensor candidate for the dRICH. They provide a cheap, highly efficient technology and they are not sensitive to the high magnetic field. The general features of the detector, a detailed view of the prototype and its different configurations, the test beam performed, and the preliminary results we obtained are presented.

We present a mixed-signal ASIC, called ALCOR (A Low-power Chip for Optical sensor Readout), designed for the readout and digitization of signals from Silicon Photomultipliers (SiPMs) in the framework of the dualradiator RICH (dRICH) detector of the electron-Proton/Ion Collider (ePIC) experiment at the Electron-Ion Collider (EIC). ALCOR features 32 channels arranged in an 8x4 matrix. The amplifier input stage is a low impedance current conveyor based on a regulated common-gate topology. The versatile front-end is able to work with positive or negative input polarity signals and includes four gain settings and two discriminators with 6-bit DAC programmable thresholds. Each channel also incorporates quad-buffered low-power TDCs based on analogue interpolation providing precise timestamping with a 25-50 ps time bin. ALCOR is designed in a 110 nm CMOS technology and the power consumption is about 10-12 mW per channel. The ASIC has been extensively tested in the laboratory standalone and coupled to different SiPM models to assess its functionality and performance. The results have been validated in a beam test campaign with a prototype of the dRICH detector and 1280 3 x 3 mm(2) SiPM sensors.

The Spin Physics Detector, a universal facility for studying the nucleon spin structure and other spin-related phenomena with polarized proton and deuteron beams, is proposed to be placed in one of the two interaction points of the NICA collider that is under construction at the Joint Institute for Nuclear Research (Dubna, Russia). At the heart of the project there is huge experience with polarized beams at JINR. The main objective of the proposed experiment is the comprehensive study of the unpolarized and polarized gluon content of the nucleon. Spin measurements at the Spin Physics Detector at the NICA collider have bright perspectives to make a unique contribution and challenge our understanding of the spin structure of the nucleon. In this document the Conceptual Design of the Spin Physics Detector is presented.

We study the spin-exotic $J^{PC} = 1^{-+}$ amplitude in single-diffractive dissociation of 190 GeV$/c$ pions into $\pi^-\pi^-\pi^+$ using a hydrogen target and confirm the $\pi_1(1600) \to \rho(770) \pi$ amplitude, which interferes with a nonresonant $1^{-+}$ amplitude. We demonstrate that conflicting conclusions from previous studies on these amplitudes can be attributed to different analysis models and different treatment of the dependence of the amplitudes on the squared four-momentum transfer and we thus reconcile their experimental findings. We study the nonresonant contributions to the $\pi^-\pi^-\pi^+$ final state using pseudo-data generated on the basis of a Deck model. Subjecting pseudo-data and real data to the same partial-wave analysis, we find good agreement concerning the spectral shape and its dependence on the squared four-momentum transfer for the $J^{PC} = 1^{-+}$ amplitude and also for amplitudes with other $J^{PC}$ quantum numbers. We investigate for the first time the amplitude of the $\pi^-\pi^+$ subsystem with $J^{PC} = 1^{--}$ in the $3\pi$ amplitude with $J^{PC} = 1^{-+}$ employing the novel freed-isobar analysis scheme. We reveal this $\pi^-\pi^+$ amplitude to be dominated by the $\rho(770)$ for both the $\pi_1(1600)$ and the nonresonant contribution. We determine the $\rho(770)$ resonance parameters within the three-pion final state. These findings largely confirm the underlying assumptions for the isobar model used in all previous partial-wave analyses addressing the $J^{PC} = 1^{-+}$ amplitude.

COMPASS is a fixed target experiment at CERN SPS aimed to study hadron structure and spectroscopy. Hadron identification in the momentum range between $3$ and $55 GeV/c$ is provided by a large gaseous Ring Imaging Cherenkov Counter, RICH-1. To cope with the challenges imposed by the new physics program of COMPASS, RICH-1 has been upgraded by replacing four MWPC-based photon detectors with newly developed MPGD-based photon detectors. The architecture of the novel detectors is a hybrid combination of two layers of THGEMs and a Micromegas. The top of the first THGEM is coated with CsI acting as a reflective photo-cathode. The anode is segmented in pads capacitively coupled to the APV-25 based readout. The new hybrid detectors have been commissioned during the 2016 COMPASS data taking and stably operated during the 2017 run. In this paper design, construction, operation and performance aspects of the novel photon detectors for COMPASS RICH-1 are discussed.

MPGD are the new frontier in gas trackers. Among this kind of devices, theGEM chambers are widely used. The experimental signals acquired with the detector mustobviously be reconstructed and analysed. In this contribution, a new offline software to performreconstruction, alignment and analysis on the data collected with APV-25 and TIGER ASICswill be presented. GRAAL (Gem Reconstruction And Analysis Library) is able to measurethe performance of a MPGD detector with a strip segmented anode (presently). The code isdivided in three parts: reconstruction, where the hits are digitized and clusterized; tracking,where a procedure fits the points from the tracking system and uses that information to align thechamber with rotations and shifts; analysis, where the performance is evaluated (e.g. efficiency,spatial resolution,etc.). The user must set the geometry of the setup and then the programreturns automatically the analysis results, taking care of different conditions of gas mixture,electric field, magnetic field, geometries, strip orientation, dead strip, misalignment and manyothers.

Triple-GEM detectors are a well known technology in high energy physics. In order to have a complete understanding of their behavior, in parallel with on beam testing, a Monte Carlo code has to be developed to simulate their response to the passage of particles. The software must take into account all the physical processes involved from the primary ionization up to the signal formation, e.g. the avalanche multiplication and the effect of the diffusion on the electrons. In the case of gas detectors, existing software such as Garfield already perform a very detailed simulation but are CPU time consuming. A description of a reliable but faster simulation is presented here: it uses a parametric description of the variables of interest obtained by suitable preliminary Garfield simulations and tuned to the test beam data. It can reproduce the real values of the charge measured by the strip, needed to reconstruct the position with the Charge Centroid method. In addition, particular attention was put to the simulation of the timing information, which permits to apply also the micro-Time Projection Chamber position reconstruction, for the first time on a triple-GEM. A comparison between simulation and experimental values of some sentinel variables in different conditions of magnetic field, high voltage settings and incident angle will be shown.

Novel gaseous detectors of single photons for RICH applications have been developed and installed on COMPASS RICH-1 in 2016. They have a hybrid architecture consisting of two staggered THGEM layers (one equipped with a CsI photoconverting layer) and a bulk Micromegas; they cover a total area of 1.4 squared meters and operate stably and efficiently. They provide a single photon angular resolution of 1.8 mrad and about 10 detected photons per ring at saturation. The main aspects of their construction and commissioning, their characterization and performance figures are presented.

The experiment BESIII, running at the accelerator BEPCII in Beijing (P.R.C.), is going to be updated with the replacement of the Inner Drift Chamber with a Cylindrical triple-GEM Inner Tracker (CGEM-IT). In the R&D stage, two standalone C++ codes were implemented: GTS (Garfield-based Triple-GEM Simulator), for digitization and tuning of simulated data to the experimental ones, and GRAAL (GEM Reconstruction And Analysis Library), for the reconstruction and analysis of the experimental events collected in testbeams. GTS simulates the triple-GEM response to the particle passage, treating each stage separately: ionization, GEM properties, gas mixture, magnetic field and finally the induction of the signal on the anode. The necessary information was extracted by GARFIELD++ simulations, parametrized and used as input in GTS. This speeds up the simulation, since GTS performs only samplings instead of the full digitization chain. The simulated events were reconstructed with the same procedure used for experimental data and tuning factors were evaluated to obtain a satisfactory match. GRAAL is used in the analysis of the testbeam experimental data. It provides several levels of reconstruction: from the cluster formation, gathering contiguous firing strips, to the spatial position and the signal time reconstruciton. Two algorithms are used: the charge centroid and the micro-TPC, which exploit the charge deposition on the strips and the time information. Also a merging of the two algorithms is available to efficiently weight the two outcomes and obtain the best estimate of the spatial coordinate. Moreover, GRAAL performs tracking and alignment. Both codes are going to be made available also for other MPGDs simulation and reconstruction.

Gas detector are very light instrument used in high energy physics to measure the particle properties: position and momentum. Through high electric field is possible to use the Gas Electron Multiplier (GEM) technology to detect the charged particles and to exploit their properties to construct a large area detector, such as the new IT for BESIII. The state of the art in the GEM production allows to create very large area GEM foils (up to 50x100 $\mathrm{cm}^2$) and thanks to the small thickness of these foils is it possible to shape it to the desired form: a Cylindrical Gas Electron Multiplier (CGEM) is then proposed. The innovative construction technique based on Rohacell, a PMI foam, will give solidity to cathode and anode with a very low impact on material budget. The entire detector is sustained by Permaglass rings glued at the edges. These rings are used to assembly the CGEM, together with a dedicated Vertical Insertion System and moreover they host the On-Detector electronic. The anode has been improved w.r.t. the state of the art through a jagged readout that minimize the inter-strip capacitance. The mechanical challenge of this detector requires a precision of the entire geometry within few hundreds of microns in the whole area. In this contribution an overview of the construction technique, the validation of this technique through the realization of a CGEM, and its first tests will be presented. These activities are performed within the framework of the BESIIICGEM Project (645664), funded by the European Commission in the action H2020-RISE-MSCA-2014.

A mixed-signal ASIC for timing and energy measurements with radiation detectors is described. The chip embeds 64 channels, each of which features a charge-sensitive amplifier followed by a dual-shaper coupled to low-offset discriminators. A versatile back-end, incorporating low-power Time to Digital Converters and Wilkinson Analog to Digital Converters with derandomizing buffers allows to encode both the time of arrival and the charge of the input signal. The ASIC is designed for a maximum detector capacitance of 100 pF and an event rate in excess of 60 kHz per channel. A peak detector samples the input signal with an excellent linearity in the range 5 divided by 55 fC. Charge digitization with Time-over-Threshold is also supported to extend the dynamic range. Fabricated in a 110 nm CMOS process, the chip dissipates 10 mW/channel. The ASIC was primarily developed to readout the cylindrical GEM detector of the BESIII experiment. For its characteristics it can serve however a broad class of radiation sensors, including silicon microstrip detectors.

Performance of triple GEM prototypes in strong magnetic field has been evaluated by means of a muon beam at the H4 line of the SPS test area at CERN. Data have been reconstructed and analyzed offline with two reconstruction methods: the charge centroid and the micro-Time-Projection-Chamber exploiting the charge and the time measurement respectively. Depending on the combination of the particle incident angle and magnetic filed, there's always one of the two algorithms achieving a spatial resolution of 100–120 μm.

Triple-GEM detectors are a well known technology used in high energy physics experiments. A reliable Monte Carlo simulation has to be developed to reproduce the performance which have been measured experimentally, for example in beam tests, and be able to infer the future behavior in real conditions. In detail, the software has to simulate the response of the detector to the passage of particles, from the primary ionization, to the amplification and diffusion of the electrons and eventually to the induction of the charge on the anode strips. In the case of gas detectors, existing softwares such as GARFIELD++ already perform a very detailed simulation of the physical processes but are CPU time consuming. In this presentation a description of a faster simulation is presented. It models the results about the electron production (primary ionization and avalanche) and diffusion in a triple-GEM obtained from GARFIELD++ and then it reconstructs the signal induced on each anode strip according to the Shockley-Ramo theorem. The simulation has been tuned on the data collected in several beam tests and it can reproduce the real values of time and charge measured by the strip. When the reconstruction algorithms used in the field of Micro Pattern Gas Detectors, such as the Charge Centroid or the micro-Time Projection Chamber readout, are applied on the simulated data, the model shows performance comparable to the experimental one. This provides a validation of this model and allows to extend its usage in different conditions, i.e. geometries, presence of magnetic field, high voltage settings, different direction of the incident particles, to evaluate the expected outcome of the triple-GEM in those cases.

G. Mezzadrib,i∗, M. Alexeev f , A. Amoroso f ,l, R. Baldini Ferrolia,c, M. Bertanic, D. Bettonib, F. Bianchi f ,l, A. Calcaterrac, N. Canaleb, M. Capodiferroc,e, V. Carassitib, S. Cerionic, JY. Chaia, f ,h, S. Chiozzib, G. Cibinettob, F. Cossio f ,h, A. Cotta Ramusinob, F. De Mori f ,l, M. Destefanis f ,l, J. Dongc, F. Evangelistib, R. Farinellib,i, L. Fava f , G. Felicic, E. Fioravantib, I. Garziab,i, M. Gattac, M. Greco f ,l, L. Lavezzia, f , CY. Lenga, f ,h, H. Lia, f , M. Maggiora f ,l, R. Malagutib, A. Mangonid,k, S. Marcello f ,l, M. Melchiorrib, M. Mignone f , G. Morelloc, S. Pacettid,k, P. Patteric, J. Pellegrino f ,l, A. Pelosic,e, A. Rivetti f , M. D. Rolo f , M. Savriéb,i, M. Scodeggiob,i, E. Soldanic, S. Sosio f ,l, S. Spataro f ,l, E. Tskhadadzec,g, S. Vermai, R. Wheadon f , L. Yan f

Gas detector development is one of the pillars of the research in fundamental physics. Since several years, a new concept of detectors, called Micro Pattern Gas Detector (MPGD), allowed to overcome several problems related to other types of commonly used detectors, like drift chamber and micro strips detectors, reducing the rate of discharges and providing better radiation tolerance. Among the most used MPGDs are the Gas Electron Multipliers (GEMs). Invented by Sauli in 1997, nowadays GEMs have become an important reality for particle detectors in high energy physics. Commonly deployed as fast timing detectors and triggers, their fast response, high rate capability and high radiation hardness make them also suitable as tracking detectors. The readout scheme is one of the most important features in tracking technology. Analog readout based on the calculation of the center of gravity technique allows to overcome the limit imposed by digital pads, whose spatial resolution is limited by the pitch dimensions. However, the presence of high external magnetic fields can distort the electronic cloud and affect the performance. The development of the micro-TP C reconstruction method brings GEM detectors into a new prospective, improving significantly the spatial resolution in presence of high magnetic fields. This innovative technique allows to reconstruct the 3-dimensional particle position, as Time Projection Chamber, but within a drift gap of a few millimeters. In these report, the charge centroid and micro-TP C methods are described in details. We discuss the results of several test beams performed with planar chambers in magnetic field. These results are one of the first developments of micro-TP C technique for GEM detectors, which allows to reach unprecedented performance in a high magnetic field of 1 T.

COMPASS is a fixed target experiment at CERN SPS aimed to study Hadron Structure and Spectroscopy. Hadron Identification in the momentum range between 3 and 55 GeV/c is provided by a large gaseous Ring Imaging Cherenkov Counter (RICH-1). To cope with the challenges imposed by the new physics program of COMPASS, RICH-1 has been upgraded by replacing four MWPCs based photon detectors with newly developed MPGD based photon detectors. The architecture of the novel detectors is a hybrid combination of two layers of THGEMs and a MicroMegas. The top of the first THGEM is coated with CsI acting as a reflective photo-cathode. The anode is segmented in pads capacitively coupled to the APV-25 based readout. The new hybrid detectors have been commissioned during 2016 COMPASS data taking and stably operated during 2017 run. In this paper all aspects of the novel photon detectors for COMPASS RICH-1 are discussed.

Gas detector are very light instrument used in high energy physics to measure the particle properties: position and momentum. Through high electric field is possible to use the Gas Electron Multiplier (GEM) technology to detect the particles and to exploit the its properties to construct a large area detector, such as the new IT for BESIII. The state of the art in the GEM production allow to create very large area GEM foils (up to 50x100 cm2) and thanks to the small thickness of these foil is it possible to shape it to the desired form: a Cylindrical Gas Electron Multiplier (CGEM) is then proposed. The innovative construction technique based on Rohacell, a PMI foam, will give solidity to cathode and anode with a very low impact on material budget. The entire detector is sustained by permaglass rings glued at the edges. These rings are use to assembly the CGEM together with a dedicated Vertical Insertion System and moreover there is placed the On-Detector electronic. The anode has been improved w.r.t. the state of the art through a jagged readout that minimize the inter-strip capacitance. The mechanical challenge of this detector requires a precision of the entire geometry within few hundreds of microns in the whole area. In this presentation will be presented an overview of the construction technique and the validation of this technique through the realization of a CGEM and its first tests. These activities are performed within the framework of the BESIIICGEM Project (645664), funded by the European Commission in the action H2020-RISE-MSCA-2014.

For the readout of the upgraded inner tracker of the BESIII experiment based on a innovative lightweight Cylindrical Gas Electron Multiplier technology a custom readout electronics is being developed. The special feature of this new front-end is the ability to perform an analog charge measurement in parallel to the event time stamp, operating in a constrained power envelop within a superconductive solenoid. The core of the new front-end is a custom designed 64ch ASIC featuring a fully digital output and operated in triggerless mode. Sustained rate per channel is up to 60 kHz. The TDCs time resolution is better than 100 ps. The energy measurement can be obtained from a time-over-threshold (ToT) measurement or by a 10-bit digitization of the peak amplitude by a sample and hold circuit (S/H).