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A wearable, flexible and non-toxic pH sensor was fabricated by assembling a cotton fabric treated with an organically modified silicate (ORMOSIL) together with a miniaturized and low-power electronics with wireless interface. The pH sensible ORMOSIL was obtained via sol–gel by using litmus, a non-toxic pH indicator, and 3-glycidoxypropyltrimethoxysilane (GPTMS) as siloxane precursor. The chemical structure of the ORMOSIL was analyzed by FTIR and UV–vis spectroscopy. The electronics has been first characterized in a standalone fashion, and successively it has been coupled to the smart fabric, in the laboratory and in preliminary on-body trials. A sweat real-time monitoring is particularly attractive for healthcare, fitness and wellness areas.

A new Multi-Walled Carbon Nanotubes (MWCNTs) based conducting cotton fabric was properly designed and achieved, as a useful component for the development of humidity and temperature sensors. A synthetic strategy was optimized through subsequent steps of MWCNTs functionalization and dispersion in a polymer matrix, by first reacting functionalized MWCNTs, 1,2,3,4-butanetetracarboxylic acid (BTCA), polyvinyl alcohol (PVA), and then adding a polyacrylic resin. The polymeric paste thus obtained, containing a synthetic thickener, was applied by a knife-over-roll coating technique onto cotton fabric, then dried and finally cured. The polymeric coated textile sample was analyzed with different chemical-physical techniques to determine its morphological features, thermal behavior and surface resistance. Changes in surface resistance of the film were monitored as a function of relative humidity and temperature variation. The electrical resistance properties of the film deposited on cotton surface seem to be clearly influenced by the presence of water molecules interacting with MWCNTs junctions. This efficient functional fabric may be a helpful starting point to develop technical textiles, or the component of a humidity sensor, useful as dual-functional sensing material for detection of environmental humidity/temperature variations.

The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray species to understand cosmic-ray production and propagation in the Galaxy. For instance, low-energy antideuterons would provide a "smoking gun" signature of dark matter annihilation or decay, essentially free of astrophysical background. Studies in recent years have emphasized that models for cosmic-ray antideuterons must be considered together with the abundant cosmic antiprotons and any potential observation of antihelium. Therefore, a second dedicated Antideuteron Workshop was organized at UCLA in March 2019, bringing together a community of theorists and experimentalists to review the status of current observations of cosmic-ray antinuclei, the theoretical work towards understanding these signatures, and the potential of upcoming measurements to illuminate ongoing controversies. This review aims to synthesize this recent work and present implications for the upcoming decade of antinuclei observations and searches. This includes discussion of a possible dark matter signature in the AMS-02 antiproton spectrum, the most recent limits from BESS Polar-II on the cosmic antideuteron flux, and reports of candidate antihelium events by AMS-02; recent collider and cosmic-ray measurements relevant for antinuclei production models; the state of cosmic-ray transport models in light of AMS-02 and Voyager data; and the prospects for upcoming experiments, such as GAPS. This provides a roadmap for progress on cosmic antinuclei signatures of dark matter in the coming years.

A low-noise, mixed-signal, 128-channel CMOS integrated circuit containing the complete readout electronics for the BABAR Silicon Vertex Tracker has been developed. The outstanding feature of the present implementation is the ability to perform simultaneously low-level signal acquisition, derandomizing data storage, sparsification and data transmission on a single monolithic chip. The signals from the detector strips are amplified, shaped by a CR-RC/sup 2/ filter with digitally selectable peaking time of 100 ns, 200 ns, 300 ns, or 400 ns, and then presented to a time-over-threshold processor to implement a compression type analog-to-digital conversion. The digital information is stored, sparsified and read out through a serial link upon receipt of a command. The digital section operates from a 60 MHz incoming clock. Noise measurements at 200 ns peaking time and 3.5 mW total power dissipation per channel yield an equivalent noise charge of 600 el. rms at 12 pF added source capacitance. The chip measures 5.7 mm/spl times/8.3 mm and contains 330 k transistors. The first full-scale prototype was fabricated in a radiation soft 0.8 /spl mu/m, 3-metal CMOS process. The same circuit is now being fabricated in an analogous radiation hard technology.

The impact of foundry-to-foundry variability and bias conditions during irradiation on the Total Ionizing Dose (TID) response of commercial 130-nm CMOS technologies have been investigated for applications in High Energy Physics (HEP) experiments. n- and p-channel MOSFETs from three different manufacturers have been irradiated with X-rays up to more than 100 Mrad (SiO2). Even though the effects of TID are qualitatively similar, the amount of degradation is shown to vary considerably from foundry to foundry, probably depending on the processing of the STI oxide and/or doping profile in the substrate. The bias during irradiation showed to have a strong impact as well on the TID response, proving that exposure at worst case bias conditions largely overestimates the degradation a device may experience during its lifetime. Overall, our results increase the confidence that 130-nm CMOS technologies can be used in future HEP experiments even without Hardness-By-Design solutions, provided that constant monitoring of the radiation response is carried out during the full manufacturing phase of the circuits.

<?Pub Dtl=""?> We present the development of the DSSC instrument: an ultra-high speed detector system for the new European XFEL in Hamburg. The DSSC will be able to record X-ray images with a maximum frame rate of 4.5 MHz. The system is based on a silicon pixel sensor with a DEPFET as a central amplifier structure and has detection efficiency close to 100% for X-rays from 0.5 keV up to 10 keV. The sensor will have a size of approximately 210 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\,\times\,$</tex></formula> 210 mm <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$^{2}$</tex></formula> composed of 1024 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\,\times\,$</tex></formula> 1024 pixels with hexagonal shape. Two hundred fifty six mixed signal readout ASICs are bump-bonded to the detector. They are designed in 130 nm CMOS technology and provide full parallel readout. The signals coming from the sensor are processed by an analog filter, immediately digitized by 8-bit ADCs and locally stored in an SRAM, which is able to record at least 640 frames. In order to fit the dynamic range of about <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$10^{4}$</tex> </formula> photons of 1 keV per pixel into a reasonable output signal range, achieving at the same time single 1 keV photon resolution, a non-linear characteristic is required. The proposed DEPFET provides the needed dynamic range compression at the sensor level. The most exciting and challenging property is that the single 1 keV photon resolution and the high dynamic range are accomplished within the 220 ns frame rate of the system. The key properties and the main design concepts of the different building blocks of the system are discussed. Measurements with the analog front-end of the readout ASIC and a standard DEPFET have already shown a very low noise which makes it possible to achieve the targeted single photon resolution for 1 keV photons at 4.5 MHz and also for 0.5 keV photons at half of the speed. In the paper the new experimental results obtained coupling a single pixel to an 8 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\,\times\,$</tex></formula> 8 ASIC prototype are shown. This 8 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\,\times\,$</tex> </formula> 8 ASIC comprises the complete readout chain from the analog front-end to the ADC and the memory. The characterization of a newly fabricated non-linear DEPFET is presented for the first time.

The first DSSC 1-Mpixel camera became available at the European XFEL (EuXFEL) in the Hamburg area in February 2019. It was successfully tested, installed, and commissioned at the Spectroscopy and Coherent Scattering Instrument. DSSC is a high-speed, large-area, 2-D imaging detector system optimized for photon science applications in the energy range between 0.25 and 6 keV. The camera is based on direct conversion Si sensors and is composed of 1024 ×1024 pixels of hexagonal shape with a side length of 136 μm. The 256 application-specific integrated circuits (ASICs) provide full parallel readout, comprising analog filtering, digitization, and in-pixel data storage. In order to cope with the demanding X-ray pulse time structure of the EuXFEL, the DSSC provides a peak frame rate of 4.5 MHz. The first Mpixel camera is equipped with miniaturized silicon drift detector (MiniSDD) pixel arrays. The intrinsic response of the pixels and the linear readout limit the dynamic range but allow one to achieve noise values of about 60 electrons r.m.s. at the highest frame rate. The challenge of providing high-dynamic range (~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> photons/pixel/pulse) and single-photon detection simultaneously requires a nonlinear system front end, which will be obtained with the DEPFET active pixel technology foreseen for the advanced version of the camera. This technology will provide lower noise and a nonlinear response at the sensor level. This article describes the architecture of the whole detector system together with the main experimental results achieved up to now.

The General Antiparticle Spectrometer (GAPS) is an upcoming balloon mission to measure low-energy cosmic-ray antinuclei during at least three ∼35-day Antarctic flights. With its large geometric acceptance and novel exotic atom-based particle identification, GAPS will detect ∼500 cosmic antiprotons per flight and produce a precision cosmic antiproton spectrum in the kinetic energy range of ∼ 0.07−0.21 GeV/n at the top of the atmosphere. With these high statistics extending to lower energies than any previous experiment, and with complementary sources of experimental uncertainty compared to traditional magnetic spectrometers, the GAPS antiproton measurement will be sensitive to dark matter, primordial black holes, and cosmic ray propagation. The antiproton measurement will also validate the GAPS antinucleus identification technique for the antideuteron and antihelium rare-event searches. This analysis demonstrates the GAPS sensitivity to cosmic-ray antiprotons using a full instrument simulation and event reconstruction, and including solar and atmospheric effects.

A search is reported for near-threshold structures in the J/ψJ/ψ invariant mass spectrum produced in proton-proton collisions at sqrt[s]=13 TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135 fb^{-1}. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638_{-38}^{+43}(stat)_{-31}^{+16}(syst) MeV. Another structure with even higher significance is found at a mass of 6847_{-28}^{+44}(stat)_{-20}^{+48}(syst) MeV, which is consistent with the X(6900) resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134_{-25}^{+48}(stat)_{-15}^{+41}(syst) MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference.

The observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138 fb^{-1} is presented. The observed (expected) significance is 5.6 (5.1) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured fiducial cross section for WWγ is 5.9±0.8(stat)±0.8(syst)±0.7(modeling) fb, in agreement with the next-to-leading order quantum chromodynamics prediction. The analysis is extended with a search for the associated production of the Higgs boson and a photon, which is generated by a coupling of the Higgs boson to light quarks. The result is used to constrain the Higgs boson couplings to light quarks.

A textile fabric treated with an organically modified silicate (ORMOSIL) was assembled together with a novel low-power color sensor in order to obtain a wearable and reliable pH sensor. The ORMOSIL matrix is a composite obtained via sol–gel by chemical reaction between the 3-glycidoxypropyltrimethoxysilane (GPTMS) precursor and Methyl Red (MR). To investigate the chemical structure of the organically modified silicate, a preliminary study by FTIR and UV–visible spectroscopy was performed on sensitive dye before and after the covalent bond formation with the opened epoxy ring of the precursor. It is found that the use of MR based on hybrid xerogels is successful in providing a pH sensing textile fabric with adequate operational stability. The developed color sensing device, based on a white LED and a photodiode whose spectral sensitivity curve is monotonic in the smart fabric color variation range, implements a light-to-frequency conversion. The miniaturized circuit results to be extremely low power with respect to other commercial solutions and it is thus suitable for portable applications aimed to log data even for many hours. The developed device was completely characterized using buffer solutions at different pH values. The pH sensor, composed by the smart fabric and its color sensing electronics, exhibits a dynamic range from pH 4.0 to pH 8.0 and an estimated resolution of 0.05 pH unit. Moreover, it shows excellent reproducibility, reversibility, temporal stability and a response time of 180 s when the fabric is dry and few seconds when it is wet. The developed system could find applications as a non-invasive, continuous sweat pH sensor for healthcare, fitness and wellness areas. Furthermore, it could be used as a wearable environmental sensor, for pollution monitoring or providing an additional sensing functionality in professional garments, for improving workers safety.

From the end of the twentieth century, the growing interest in a new generation of wearable electronics with attractive application for military, medical and smart textiles fields has led to a wide investigation of chemical finishes for the production of electronic textiles (e-textiles). Herein, a novel method to turn insulating cotton fabrics in electrically conductive by the deposition of three-dimensional hierarchical vertically aligned carbon nanotubes (VACNT) is proposed. Two VACNT samples with different length were synthesized and then dispersed in 4-dodecylbenzenesulfonic acid combined with silica-based sol-gel precursors. The dispersed VACNT were separately compounded with a polyurethane thickener to obtain homogeneous spreadable pastes, finally coated onto cotton surfaces by the “knife-over-roll” technique. Shorter VACNT-based composite showed the best electrical conductivity, with a sheet resistance value less than 4.0 · 104 ± 6.7 · 103 Ω/sq. As demonstrated, developed e-textiles are suitable for application as humidity sensing materials in wearable smart textiles by exhibiting adequate response time for end-users and repeatability at several exposure cycles, still maintaining excellent flexibility. The proposed environmentally-friendly and cost-effective method can be easily widened to the scalable production of CNT-containing conductive flexible coatings, providing additional support to the development of real integration between electronics and textiles.

This paper presents a study of the noise behavior of submicron CMOS transistors, in view of applications to high-density mixed-signal front-end systems for high-granularity detectors. The goal of this work is extending the knowledge in this field, presently focused on 0.25 /spl mu/m processes, to the following generation of CMOS technologies (with 0.18 /spl mu/m minimum gate length). The white component of the noise voltage spectrum, which is most important for fast signal processing, and the 1/f noise contribution are experimentally characterized with noise measurements in a wide frequency range. The results of this analysis are used to establish low-noise design criteria concerning the choice of the polarity and of the channel dimensions (length and width) of the preamplifier input device in low-power operating conditions. A comparison with similar noise measurements on CMOS devices belonging to a 0.35 /spl mu/m process allows estimating the impact of gate-length scaling on both white and 1/f noise components. The noise radiation tolerance is also a key parameter for many front-end systems. It was evaluated by exposing the devices to high doses of ionizing radiation.

This work discusses the design, carried out in the framework of the INFN Falaphel project, of analog front-end circuits for future, high-rate pixel detector applications. In particular, two front-end architectures are being developed, one with Time-over-Threshold (ToT) digitization of the input signal and the other based on an in-pixel flash ADC featuring a novel, clocked comparator conceived to dramatically reduce the threshold dispersion of the front-end. The paper includes a description of the analog processors being developed. The main analog performance parameters, as obtained from circuit simulations and including equivalent noise charge and threshold dispersion, are reported.

Rising electricity prices and the greater penetration of electricity consumption in end-uses have prompted efforts to set up data-driven methodologies to optimise energy consumption and foster user engagement in demand-side management strategies. The performance of energy-management systems is greatly affected by the consumer behaviors and the adopted energy-management methodology. Consequently, it is necessary to develop appliance-level, detailed energy-consumption information models to inform citizens to improve behaviors toward energy use. The goal of the Home Energy Management System (HEMS) is to foster an ecosystem that is energy-optimized and can manage Internet of things (IoT) equipment over its network. HEMS allows consumers to reduce energy costs by adapting their consumption to variable pricing over the day. With the use of descriptive data-mining techniques, we have developed a numerical model that gives consumers access to information on their domestic appliances with regard to the number and duration of operations, cycles disaggregation for appliances that have cyclic operation (e.g., washing machine, dishwasher), and energy consumption throughout various time periods basing on 15-min monitoring data. The model has been calibrated and validated on two datasets collected by ENEA by real-time monitoring of Italian dwellings and has been tested over several appliances showing effective analysis of the energy-consumption patterns. Therefore, it has been integrated in the DHOMUS IoT platform, developed by ENEA to monitor and analyse the energy consumption in dwellings in order to increase citizens’ engagement and awareness of their energy consumption. The results indicate that the developed model is sufficiently accurate, and that it is possible to promote a more virtuous and sustainable use of energy by end users, as well as to reduce the energy demand as required by the current European Council Regulation (EU) 2022/1854.

Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 μm have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9×1015π cm−2,5×1015 p cm−2 and 1.35×1015 n cm−2, respectively. Diamond micro-strip detectors with 50 μm pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2×4 cm2 surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out chip prototypes for ATLAS and CMS. Beam test results are shown from a diamond detector bump-bonded to an ATLAS prototype read-out. They demonstrate a 98% bump-bonding efficiency and a digital resolution in both dimensions.

CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/c and 500 Mev protons up to a fluence of 5×1015 p/cm2. We measured the charge collection distance, the average distance electron–hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1×1015 p/cm2 and decreases by ≈40% at 5×1015 p/cm2. Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/c and 500 MeV protons up to at least 1×1015p/cm2 without signal loss.

The inherent properties of diamond make it an ideal material for tracking detectors especially in the high rate, high radiation environments of future colliders such as the LHC. In order to survive in this environment, detectors must be radiation hard. We have constructed charged particle detectors using high quality CVD diamond and performed radiation hardness tests on them. The signal response of diamond detectors to ionizing particles is measured before and after irradiation. Diamond detectors have been exposed to 60Co photons at Argonne National Laboratory, 300 MeV/c pions at PSI, 500 MeV protons at TRIUMF and 5 MeV alpha particles at Los Alamos National Laboratory. The results show that CVD diamond is an extremely radiation hard material well suited for particle detector production.

This work studies the feasibility of a new implementation of CMOS monolithic active pixel sensors (MAPS) for applications to charged particle tracking. As compared to standard three MOSFET MAPS, where the charge signal is readout by a source follower, the proposed front-end scheme relies upon a charge sensitive amplifier (CSA), embedded in the elementary pixel cell, to perform charge-to-voltage conversion. The area required for the integration of the front-end electronics is mostly provided by the collecting electrode, which consists of a deep n-type diffusion, available as a shielding frame for n-channel devices in deep submicron, triple well CMOS technologies. Based on the above concept, a chip, which includes several test structures differing in the sensitive element area, has been fabricated in a 0.13μm CMOS process. In this paper, the criteria underlying the design of the pixel level analog processor will be presented, together with some preliminary experimental results demonstrating the feasibility of the proposed approach.

In this paper a Qi-standard compliant compact wireless power charger system, composed of a wireless power transmitter and a wireless power receiver, is presented. The developed system aims to be compliant with the latest revision of Wireless Power Consortium's directives and uses a full-bridge resonant inverter as the main power transmitter architecture. The wireless power transmitter and receiver have been designed with ultra low power and high efficiency electronics components thereby maximizing the overall power transfer efficiency.

The first lithium-drifted silicon (Si(Li)) detectors to satisfy the unique geometric, performance, and cost requirements of the General Antiparticle Spectrometer (GAPS) experiment have been produced by Shimadzu Corporation. The GAPS Si(Li) detectors will form the first large-area, relatively high-temperature Si(Li) detector system with sensitivity to X-rays to operate at high altitude. These 10 cm-diameter, 2.5 mm-thick, 4- or 8-strip detectors provide the active area, X-ray absorption efficiency, energy resolution, and particle tracking capability necessary for the GAPS exotic-atom particle identification technique. In this paper, the detector performance is validated on the bases of X-ray energy resolution and reconstruction of cosmic minimum ionizing particle (MIP) signals. We use the established noise model for semiconductor detectors to distinguish sources of noise due to the detector from those due to signal processing electronics. We demonstrate that detectors with either 4 strips or 8 strips can provide the required $\lesssim$4 keV (FWHM) X-ray energy resolution at flight temperatures of $-35$ to $-45^{\circ}$C, given the proper choice of signal processing electronics. Approximately 1000 8-strip detectors will be used for the first GAPS Antarctic balloon flight, scheduled for late 2021.

In this paper, a new and versatile approach to obtain a good dispersion in water-based paste of short (≅ 1.5 mm) and long (≅ 3.0 mm) millimeter-sized carbon nanotubes (CNT) for the fabrication of electroconductive textiles is reported. With this aim, N-[3-(triethoxysilyl)propyl]ethylenediamine (EDAES) was used in combination with a waterborne thermo-degradable surfactant to stabilize the dispersion of two different kinds of carbon nanotubes (CNT) in hydroalcoholic solutions. A polyurethane thickener was added to each CNT dispersion to obtain dense pastes that were deposited onto cotton fabrics using the knife-over-roll technique. High magnification images confirm that the nanotubes are well dispersed in both coatings, furthermore appearing homogeneously distributed on the cotton surface. The conductivity of the long CNT-coated fabrics was confirmed by the electrical resistance of 2.61 × 104 Ω/sq which decreased to 9.46 × 102 Ω/sq for short CNT size. Moreover, after one washing cycle, the electrical conductivity variations of coating containing the shortest nanotubes retain over 99%, demonstrating its adhesion on the fabric. The increase of the textile stiffness was less than 20% for both treated samples compared to the reference, without affecting significantly the fabric samples comfort. The developed cotton fabrics worked well as wearable conductive materials in heart rate monitoring using photoplethysmography.

The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed for low-energy (0.1–0.3 GeV/n) cosmic antinuclei as signatures of dark matter annihilation or decay. GAPS is optimized to detect low-energy antideuterons, as well as to provide unprecedented sensitivity to low-energy antiprotons and antihelium nuclei. The novel GAPS antiparticle detection technique, based on the formation, decay, and annihilation of exotic atoms, provides greater identification power for these low-energy antinuclei than previous magnetic spectrometer experiments. This work reports the sensitivity of GAPS to detect antihelium-3 nuclei, based on full instrument simulation, event reconstruction, and realistic atmospheric influence simulations. The report of antihelium nuclei candidate events by AMS-02 has generated considerable interest in antihelium nuclei as probes of dark matter and other beyond the Standard Model theories. GAPS is in a unique position to detect or set upper limits on the cosmic antihelium nuclei flux in an energy range that is essentially free of astrophysical background. In three 35-day long-duration balloon flights, GAPS will be sensitive to an antihelium flux on the level of 1.3−1.2+4.5·10−6 m-2sr-1s-1(GeV/n)-1 (95% confidence level) in the energy range of 0.11–0.3 GeV/n, opening a new window on rare cosmic physics.

KEDR is a general-purpose detector for experiments at the VEPP-4M e+e−-collider in the energy range 2E=2.0–12GeV. All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/Ψ meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.

Several steps through which the design of a monolithic preamplifier system for microstrip detectors has passed, are critically analyzed. From the very initial MOSFET version, several measures were gradually taken with the purpose of reducing noise. The latest design criteria aim at realizing a preamplifier system which, besides outstanding noise performances, features also a suitable degree of radiation tolerance.

This work is concerned with the design of a low-noise Charge Sensitive Amplifier featuring a dynamic signal compression based on the non-linear features of an inversion-mode MOS capacitor. These features make the device suitable for applications where a non-linear characteristic of the front-end is required, such as in imaging instrumentation for free electron laser experiments. The aim of the paper is to discuss a methodology for the proper design of the feedback network enabling the dynamic signal compression. Starting from this compression solution, the design of a low-noise Charge Sensitive Amplifier is also discussed. The study has been carried out by referring to a 65 nm CMOS technology.

This work is concerned with the design and the experimental characterization of analog front-end electronics conceived for experiments with unprecedented particle rates and radiation levels at future high-energy physics colliders. A prototype chip integrating different test structures has been submitted in the framework of the CHIPIX65 project. These structures are standalone channels for the readout of hybrid pixels, featuring a charge sensitive preamplifier as the first stage of the readout chain, a high-speed comparator and a circuit for fine threshold tuning. The paper thoroughly discusses the results, mainly focused on the charge sensitive amplifier, coming from the characterization of the submitted test structures.

We present a comparative study of ionizing radiation effects in 0.18 and 0.25 /spl mu/m CMOS transistors, with the goal of evaluating the impact of device scaling in the design of low-noise rad-hard analog circuits. Device parameters were monitored before and after irradiation with 10 keV X-rays and /sup 60/Co /spl gamma/-rays and after subsequent annealing. The effects of different biasing conditions during irradiation and annealing are discussed. The results are used to point out the different radiation hardness properties of the examined technologies, belonging to different CMOS generations.

This paper presents a study of the ionizing radiation tolerance of 0.13 /spl mu/m CMOS transistors, in view of the application to the design of rad-hard analog integrated circuits. Static, signal and noise parameters of the devices were monitored before and after irradiation with /sup 60/Co /spl gamma/-rays at a 10 Mrad total ionizing dose. The effects on key parameters such as threshold voltage shift and 1/f noise are studied and compared with the behavior under irradiation of devices in previous CMOS generations.

Degradation mechanisms associated to lateral isolation oxides are discussed to account for total ionizing dose effects on the noise performance of 90 nm and 130 nm CMOS devices and for their dependence on geometry and operating conditions. In NMOSFETs with a conventional open layout, after irradiation the parasitic transistor at the device edges turns on and contributes to the total device noise. The paper provides a model to help understanding the impact of this radiation-induced noise contribution on white and 1/f noise terms. The different behavior of NMOSFETs in the two examined technology nodes is analyzed in this framework, and design criteria to reduce noise degradation in irradiated devices are discussed.

A miniaturized wireless Attitude and HeadingReference System has been developed with the primary purposeto achieve a body sensor network for motor performancequantitative analysis of Parkinson's disease patients duringrehabilitation sessions. The paper describes the performance ofthe single node, the peculiarities of the developed wearablenetwork and the custom software developed specifically for theExtended Timed-Up-and-Go test. An experimental protocol onParkinson's Disease patients is currently ongoing. This paperreports the preliminary results, involving 13 patients (mean age64.6±9) with a moderate disease level and 4 controls (mean age64.3±4). The data taken during rehabilitation exercise have beenanalyzed and outcomes are discussed.

Pixel detectors at HL-LHC experiments or other future experiments are facing new challenges, especially in terms of unprecedented levels of radiation and particle flux. This paper describes the progress made by the CHIPIX65 project of INFN for the development of a new generation readout ASIC using CMOS 65 nm technology.

This paper is a review of recent progress of RD53 Collaboration. Results obtained on the study of the radiation effects on 65 nm CMOS have matured enough to define first strategies to adopt in the design of analog and digital circuits. Critical building blocks and analog very front end chains have been designed, tested before and after 5–800 Mrad. Small prototypes of 64×64 pixels with complex digital architectures have been produced, and point to address the main issues of dealing with extremely high pixel rates, while operating at very small in-time thresholds in the analog front end. The collaboration is now proceeding at full speed towards the design of a large scale prototype, called RD53A, in 65 nm CMOS technology.

In this paper, a wearable electronic platform for in-ear photoplethysmography is presented. The system is specifically designed with a miniaturized form factor in order to enable the potential monitoring of athletes during physical activity, as well as professionals wearing earbuds or headphones during their normal duties. Measurements have been collected to address the main factors affecting the signal quality. As a result, the fine tuning of the configuration parameters allowed the extension of the battery lifetime of the system to over 3 days of continuous operation. Moreover, an investigation of the best body measurement location has been carried out. Two different algorithms have been developed: the former is a lightweight procedure for heart rate (HR) estimation suitable for embedded implementation whereas the latter features a motion mitigation adaptive filter to compensate the effect of motion artifacts (MAs).

Abstract This work is concerned with the design and the characterization of front-end channels, developed in a 28 nm CMOS technology, conceived for the readout of pixel sensors in future, high-rate applications at the next generation facilities. Two front-end architectures are discussed. In the first one, an in-pixel flash ADC is exploited for the digitization of the signal, whereas the second one features a Time-over-Threshold (ToT) approach. A prototype including the ADC-based front-end has been submitted and the characterization of the chip is discussed in the paper. Simulation results relevant to the ToT-based architecture are reported.

Diamond, as the hardest material known, has an extremely high binding energy suggesting that it will be a radiation hard material. Given that it is also a semiconductor, one is led to believe that diamond might perform well as a high resolution semiconductor tracking detector in very hostile radiation environments in which more conventional detectors would fail. In this paper we, the RD42 Diamond Detector Collaboration, review the progress that we have made in the development of chemical vapor deposition (CVD) diamond as a detector material, its radiation hardness, and the performance we have achieved with diamond tracking detectors.

We designed and fabricated a novel monolithic active pixel sensor (MAPS), in STMicrolectronics 0.13μm CMOS technology, exploiting the triple well option to implement, at the pixel level, a more complex signal processor and to increase the size of the charge collecting electrode with respect to previously developed CMOS MAPS. This was possible using the deep n-well, available in triple well technology, as a sensing electrode and placing, in the same physical area, part of the readout electronics. The signal processing chain, implemented in the elementary cell, includes a low noise charge preamplifier, a shaper, a discriminator and a latch. The first prototype chips have been successfully tested with very encouraging results. In this work we present the performance of the front-end electronics and the response of the sensor to ionizing radiation.

A low material budget silicon demonstrator has been tested by the SLIM5 collaboration with 12 GeV/c protons at the PS-T9 beam line at CERN. Two devices were placed inside a reference telescope and their characteristics were measured. The first was a 4k-Pixel Matrix of Deep N Well MAPS, developed in a 130 nm CMOS technology, providing digital sparsified readout. The other one was a high resistivity double-sided silicon detector, with short strips at a 45∘ angle to the detector's edge, read out by the FSSR2 chip. In this paper we describe the main features of both sensors. The primary goal of the test was to measure the efficiency and the resolution of the DUTs under different conditions of threshold setting and incident angle of the impinging particles. The data-driven approach of the readout chips has been fully exploited by the DAQ system to take data with a track-based level-1 trigger provided by a pattern matching algorithm with very low latency.

Low noise design of charge sensitive amplifiers in deep submicron CMOS technologies is discussed based on the experimental characterization of transistors belonging to a 130 nm and a 90 nm minimum channel length processes. After briefly examining the main preamplifier noise sources, residing in the input element, achievable resolution limits in charge measuring systems employing such technologies are discussed under different detector capacitance, processing time and power dissipation constraints. The equivalent noise charge (ENC) model adopted in this work takes into account the behavior of series 1/f noise as a function of the overdrive voltage in PMOS devices. Moreover, noise in the gate current, whose effects could be neglected in past CMOS technologies featuring larger gate oxide thickness, is shown to play a role in the optimization process, significantly affecting the preamplifier performance at long shaping times. The extent of this contribution, besides depending on the drain current in the input device, is also determined by its drain voltage, which therefore may become a critical parameter in the design of low noise analog blocks.

Among movement disorders, essential tremor is by far the most common, as much as eight times more prevalent than Parkinson’s disease. Although these two conditions differ in their presentation and course, clinicians do not always recognize them, leading to common misdiagnoses. Proper and early diagnosis is important for receiving the right treatment and support. In this paper, the development of a portable and reliable tremor classification system based on a wearable device, enabling clinicians to differentiate between essential tremor and Parkinson’s disease-associated one, is reported. Inertial data were collected from subjects with a well-established diagnosis of tremor, and analyzed to extract different sets of relevant spectral features. Supervised learning methods were then applied to build several classification models, among which the best ones achieved an average accuracy above 90%. Results encourage the use of wearable technology as effective and affordable tools to support clinicians.

A search is presented for long-lived particles produced in pairs in proton-proton collisions at the LHC operating at a center-of-mass energy of 13 TeV. The data were collected with the CMS detector during the period from 2015 through 2018, and correspond to a total integrated luminosity of 140 fb$^{-1}$. This search targets pairs of long-lived particles with mean proper decay lengths between 0.1 and 100 mm, each of which decays into at least two quarks that hadronize to jets, resulting in a final state with two displaced vertices. No significant excess of events with two displaced vertices is observed. In the context of $R$-parity violating supersymmetry models, the pair production of long-lived neutralinos, gluinos, and top squarks is excluded at 95% confidence level for cross sections larger than 0.08 fb, masses between 800 and 3000 GeV, and mean proper decay lengths between 1 and 25 mm.

This work describes the architecture and the experimental results from the characterization of a 32-channels mixed-signal Application-Specific Integrated Circuit (ASIC) developed for the readout of the lithium-drifted silicon, Si(Li), detectors of the General AntiParticle Spectrometer (GAPS) experiment dedicated to searching for dark matter. The instrument is designed for the identification of antiprotons, antideuterons and antihelium nuclei from cosmic rays during an Antarctic balloon mission scheduled for late 2024. A full custom integrated circuit, named SLIDER32 (32-channels Si-LI DEtector Readout) ASIC, has been produced in a commercial 180 nm CMOS technology. The ASIC is comprised of 32 low-noise analog readout channels featuring dynamic signal compression to comply with the wide input range, an 11-bit SAR ADC and a digital back-end section which is responsible for channel setting and for sending digital information to the data acquisition system (DAQ). The circuit design criteria and the experimental results are discussed in the paper.

A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138 fb−1 of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016–2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ(pp→A′→χ1χ2) and the decay branching fraction B(χ2→χ1μ+μ−), where A′ is a dark photon and χ1 and χ2 are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter.Received 19 May 2023Revised 24 September 2023Accepted 29 November 2023DOI:https://doi.org/10.1103/PhysRevLett.132.041802Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.© 2024 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Research AreasDark matterPhysical SystemsHypothetical particlesTechniquesHadron collidersParticles & Fields

The azimuthal anisotropy of mesons in high-multiplicity proton-lead collisions is studied using data collected by the CMS experiment at a nucleon-nucleon center-of-mass energy of 8.16 TeV. The mesons are reconstructed using their dimuon decay channel. The anisotropy is characterized by the second Fourier harmonic coefficients, found using a two-particle correlation technique, in which the mesons are correlated with charged hadrons. A large pseudorapidity gap is used to suppress short-range correlations. Nonflow contamination from the dijet background is removed using a low-multiplicity subtraction method, and the results are presented as a function of transverse momentum. The azimuthal anisotropies are smaller than those found for charmonia in proton-lead collisions at the same collision energy, but are consistent with values found for mesons in lead-lead interactions at a nucleon-nucleon center-of-mass energy of 5.02 TeV.

Two-particle Bose--Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of $\sqrt{{s}_{\mathrm{NN}}}=5.02\phantom{\rule{4pt}{0ex}}\mathrm{TeV}$. The data sample, containing $4.27\ifmmode\times\else\texttimes\fi{}{10}^{9}$ minimum bias events corresponding to an integrated luminosity of 0.607 ${\text{nb}}^{\ensuremath{-}1}$, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a L\'evy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the L\'evy index or shape parameter $\ensuremath{\alpha}$, the L\'evy scale parameter $R$, and the correlation strength parameter $\ensuremath{\lambda}$. The source shape, characterized by $\ensuremath{\alpha}$, is found to be neither Cauchy nor Gaussian, implying the need for a full L\'evy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a hydrodynamical scaling is observed for the L\'evy $R$ parameter. The $\ensuremath{\lambda}$ parameter is studied in terms of the core-halo model.

Abstract The Belle II collaboration has initiated a program to upgrade its detector in order to address the challenges set by the increase of the SuperKEKB collider luminosity, targeting 6×10 35 cm 2 s -1 . A monolithic CMOS pixel sensor named OBELIX (Optimized BELle II pIXel) is proposed to equip 5 detection layers upgrading the current vertex detector. Based on the existing TJ-Monopix2, OBELIX is currently designed in 180 nm CMOS process.

A search for the lepton flavor violating τ→3μ decay is performed using proton-proton collision events at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC in 2017–2018, corresponding to an integrated luminosity of 97.7 fb−1. Tau leptons produced in both heavy-flavor hadron and W boson decays are exploited in the analysis. No evidence for the decay is observed. The results of this search are combined with an earlier null result based on data collected in 2016 to obtain a total integrated luminosity of 131 fb−1. The observed (expected) upper limits on the branching fraction B(τ→3μ) at confidence levels of 90 and 95% are 2.9×10−8 (2.4×10−8) and 3.6×10−8 (3.0×10−8), respectively.

An analog signal processor based on the Time-over-Threshold (ToT) range compression is employed in the front-end section of the readout chip of the microstrip vertex detector for the BaBar experiment. The paper, after describing the circuit solutions that have been adopted to optimize the ToT operation, focuses on the noise aspects of the ToT processor. Comparisons are made between the signal-to-noise ratio in the linear processor preceding the ToT circuit and that obtained at the output of the entire analog channel including the ToT function.

High-density high-speed CMOS and BiCMOS technologies are today widely used for the design of readout integrated circuits for room-temperature X- and /spl gamma/-ray imaging detectors. This paper describes a laboratory instrument that was developed to characterize the noise performances of CMOS devices to be used for high-speed analog signal processing. This instrument extends the noise-measuring capabilities beyond 100 MHz to detect the white noise component beyond the 1/f noise corner frequency, which in shorter channel devices shifts to higher values as compared to long-channel transistors.

This paper presents a study of the ionizing radiation tolerance of analog parameters of 0.18-/spl mu/m CMOS transistors, in view of the application to the design of front-end integrated circuits for detectors in high-energy physics experiments. Static, signal, and noise performances of devices with various gate dimensions were monitored before and after irradiation up to a 300-kGy(Si) total dose of /sup 60/Co /spl gamma/-rays. Different device biasing conditions under irradiation were used, and the relevant results are discussed. A comparison with previous CMOS generations is carried out to evaluate the impact of device scaling on the radiation sensitivity.

This paper is intended to discuss the features of a novel kind of monolithic active pixel sensors (MAPS) in deep submicron CMOS technology (130 nm minimum feature size) for use in charged particle trackers and vertex detectors. As compared to conventional MAPS with 3-transistor readout scheme, the design approach proposed here, where a deep N-well (DNW) is used as the collecting electrode, lends itself to pixel-level sparsified processing and is expected to provide the ability to manage the large data flow of information anticipated for future, high luminosity colliders. Lately, the applicability of the DNW-MAPS concept to the design of the vertex detector for future high luminosity colliders, like the International Linear Collider (ILC), has been investigated. This paper will discuss the design and performance of a recently submitted DNW monolithic sensor, the SDR0 (Sparsified Digital Readout) chip, including different test structures, where both analog (charge amplification and threshold discrimination) and digital (sparsification, time stamping) functions have been integrated inside the elementary sensor, as large as 25μm×25μm.

The FSSR2 is the second release of the Fermilab Silicon Strip Readout Chip. The chip has been designed and fabricated in a 0.25 mum CMOS technology for high radiation tolerance. The first release, simply called the FSSR, was a prototype version with many different analog front-end configurations. The best solution was chosen for the FSSR2 chip to optimize the noise, according to criteria discussed in this paper. The FSSR2 has been designed for the silicon strip detectors of the BTeV experiment. The chip services 128 strips and provides address, time and magnitude information for all hits. Several programmable features are included in FSSR2, such as an internal pulser, a baseline restorer and a signal peaking time selectable among four values in the range between 65 ns and 125 ns. The circuit design and the performance of FSSR2 are discussed in this paper

Irradiation tests on 90 nm CMOS devices at different total ionizing doses lead to new insights into degradation mechanisms in gate oxides and lateral isolation structures and into their impact on gate and drain current noise sources. The action of lateral parasitic transistors and their physical parameters are studied in different operating conditions. The main focus is on 1/f noise, which is one of the few parameters which are sizably affected by irradiation. Irradiation effects on the noise in the gate current are discussed in this paper for the first time. The analysis of the behavior of thick oxide I/O transistors provides a comparison both with thin oxide core devices and with previous, less scaled CMOS generations.

In the last few years CMOS commercial technologies of the quarter micron node have been extensively used in the design of the readout electronics for highly granular detection systems in the particle physics environment. IC designers are now moving to 130 nm CMOS technologies, or even to the next technology generation, to implement readout integrated circuits for future HEP applications. In order to evaluate how scaling down of the device features affects their performances, continuous technology monitoring is mandatory. In this work the results of signal and noise measurements carried out on two CMOS commercial processes are presented. Data obtained from the measurements provide a powerful tool to establish design criteria in nanoscale CMOS processes for detector front-ends and can be used to evaluate the resolution limits achievable for low-noise charge sensitive amplifiers in the 100-nm minimum feature size range.

A fine pitch, deep N-well CMOS monolithic active pixel sensor (DNW CMOS MAPS) with sparsified readout architecture and time stamping capabilities has been designed in a vertical integration (3D) technology. In this process, two 130 nm CMOS wafers are face-to-face bonded by means of thermo-compression techniques ensuring both the mechanical stability of the structure and the electrical interconnection between circuits belonging to different layers. This 3D design represents the evolution of a DNW monolithic sensor already fabricated in a planar 130 nm CMOS technology in view of applications to the vertex detector of the International Linear Collider (ILC). The paper is devoted to discussing the main design features and expected performance of the 3D DNW MAPS. Besides describing the front-end circuits and the general architecture of the detector, the work also provides some results from calculations and Monte Carlo device simulations comparing the old 2D solution with the new 3D one and illustrating the attainable detection efficiency improvements.

This report describes the present status of the detector design for SuperB. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.

The CMS tracker at HL-LHC is required to provide prompt information on particles with high transverse momentum to the central Level 1 trigger. For this purpose, the innermost part of the outer tracker is based on a combination of a pixelated sensor with a short strip sensor, the so-called Pixel-Strip module (PS). The readout of these sensors is carried out by distinct ASICs, the Strip Sensor ASIC (SSA), for the strip layer, and the Macro Pixel ASIC (MPA) for the pixel layer. The processing of the data directly on the front-end module represents a design challenge due to the large data volume (30720 pixels and 1920 strips per module) and the limited power budget. This is the reason why several studies have been carried out to find the best compromise between ASICs performance and power consumption. This paper describes the current status of the MPA ASIC development where the logic for generating prompt information on particles with high transverse momentum is implemented. An overview of the readout method is presented with particular attention on the cluster reduction, position encoding and momentum discrimination logic. Concerning the architectural studies, a software test bench capable of reading physics Monte-Carlo generated events has been developed and used to validate the MPA design and to evaluate the MPA performance. The MPA-Light is scheduled to be submitted for fabrication this year and will include the full analog functions and a part of the digital logic of the final version in order to qualify the chosen VLSI technology for the analog front-end, the module assembly and the low voltage digital supply.

A front-end channel prototype for pixel detectors has been designed for the upgrades of the HL-LHC experiments. The circuit is based on a Krummenacher feedback network to continuously reset the charge sensitive amplifier and on a fast threshold discriminator to implement a time-over-threshold (ToT) method and perform amplitude measurement. The front-end circuit was developed in a 65 nm CMOS technology and takes an overall area not exceeding 1250 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , i.e., half of the overall pixel area. The current consumption per channel is around 4 μA at VDD = 1.2 V. A very small charge sensitivity dispersion was detected in the set of characterized samples. An equivalent noise charge of 120 e <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> was found for a detector capacitance of 100 fF. The response of the channel is compatible with the speed requirements of the foreseen application in the innermost layers of the CMS pixel detector.

Diamond may make an excellent substrate for a tracking device in the near future, especially at colliders like LHC, where extreme running conditions are expected (high rates and high radiation levels). We report on neutron irradiation of several CVD-diamond samples at the ISIS facility (Rutherford Appleton Laboratory), which provides a fast neutron spectrum similar to that expected in a high luminosity collider experiment like CMS. We measured beam-induced currents and charge collection of diamonds exposed to fluences in excess of 1015 n/cm2 (peaking at 1 MeV), which should be the maximum value of the ten years total fluence at the design LHC luminosity. Physical hypotheses for the interactions of neutrons on CVD-diamond are proposed.

This paper discusses the behaviour of a prototype rad-hard version of the chip developed for the readout of the BaBar silicon vertex tracker. A previous version of the chip, implemented in the 0.8 μm HP rad-soft version has been thoroughly tested in the recent times. It featured outstanding noise characteristics and showed that the specifications assumed as target for the tracker readout were met to a very good extent. The next step was the realization of a chip prototype in the rad-hard process that will be employed in the actual chip production. Such a prototype is structurally and functionally identical to its rad-soft predecessor. However, the process parameters being different, and not fully mastered at the time of design, some deviations in the behaviour were to be expected. The reasons for such deviations have been identified and some of them were removed by acting on the points that were left accessible on the chip. Other required small circuit modifications that will not affect the production schedule. The tests done so far on the rad-hard chip have shown that the noise behaviour is very close to that of the rad-soft version, that is fully adequate for the vertex detector readout.

Deep-submicron complementary MOS processes have made the development of ASICs for HEP instrumentation possible. In the last few years CMOS commercial technologies of the quarter micron node have been extensively used in the design of the readout electronics for highly granular detection systems in the particle physics environment. IC designers are now moving to 130 nm CMOS technologies, or even to the next technology node, to implement readout integrated circuits for silicon strip and pixel detectors, in view of future HEP applications. In order to evaluate how scaling down of the device features affects their performances, continuous technology monitoring is mandatory. In this work the results of signal and noise measurements carried out on CMOS devices in 130 nm and 90 nm commercial processes are presented. Data obtained from the measurements provide a powerful tool to establish design criteria in nanoscale CMOS processes for detector front-ends and can be used to evaluate the resolution limits achievable for low-noise charge sensitive amplifiers in the 100-nm minimum feature size range.

The Italian silicon-detectors-with-low-interaction-with material collaboration (SLIM5) has designed, fabricated and tested several prototypes of CMOS monolithic active pixel sensors (MAPS). This paper shows the design of a new mixed-mode chip prototype composed of a bidimensional matrix of pixels, and of an off-pixel digital readout sparsification circuit. The readout logic is based on commercial standard cells and implements an optimized non token readout technique. Also, a MAPS emulator software toool is presented. The project is aimed at overcoming the readout speed limit of future large-matrix pixel detectors for particle tracking, by matching the requirements of future high-energy physics experiments. The readout architecture extends the flexibility of the MAPS devices to be also used in first level triggers on tracks in vertex detectors.

Dialysis adequacy, assessed by urea kinetics, is an important determinant of patient outcome, and is therefore an important clinical performance indicator. In this perspective, renal registry data may be useful to compare practices across countries. To serve that purpose available data should be comparable and preferably collected using a standardized procedure. The aim of this study, initiated by the European Renal Association-European Dialysis and Transplantation Association (ERA-EDTA) QUality European STudies (QUEST) initiative, was to make an inventory of the different methods used to determine urea kinetic measurements in the light of the European Best Practice Guidelines.Via their national and regional registries, European haemodialysis centres were invited to complete a questionnaire regarding their practice of measuring dialysis adequacy.Fourteen regional or national registries among 51 sent back 255 questionnaires. Great variability in the methodology to assess Kt/V was observed. The urea reduction ratio (URR) was used alone by 37% (in association 46%) of dialysis centres, spKt/V by 25% (35%) and on-line clearance by 4% (12%), whereas only 10% (13%) used eKt/V, as recommended by EBPG. Forty percent of centres measured urea removal less than once a month, 6% of which never measured urea removal and 9% only every 6 months or less frequently.Despite the fact that the use of URR is not recommended by EBPG, it was the most commonly used indicator to measure urea removal, whereas eKt/V was only used by a small minority of centres. This study allowed us to point out the need to standardize definitions and procedures and to develop an effective plan for implementation of the guidelines.

The large scale of integration provided by CMOS processes with minimum feature size in the 100 nm range, makes them very attractive in the design of front-end electronics for highly pixelated detectors, where several functions need to be packed inside a relatively small silicon area. Nowadays, processes with 130 nm minimum channel length are widely available for Application Specific Integrated Circuits (ASICs) design, nonetheless designers are considering more scaled technologies following the trend of commercial silicon foundries. This work provides an extensive analysis of the noise performance which can be attained by detector front-end circuits in a 65 nm CMOS process. The behavior of the 1/f and white noise terms in this technology node is studied as a function of the device polarity, of the gate length and width and of the bias conditions. A comparison with data from previous CMOS generations is also carried out to evaluate the impact of scaling down to the 65 nm node.

Experimental data provide insight into the mechanisms governing the impact of gate and lateral isolation dielectrics and of scaling-related technological advances on noise and its sensitivity to total ionizing dose effects in Low Power 65 nm CMOS devices. The behavior of the 1/f noise term is correlated with the effects on the drain current that irradiation brings along by turning on lateral parasitic transistors. A comparison with data from previous CMOS generations is carried out to assess the impact of process features on radiation-induced degradation effects.

The high luminosity SuperB asymmetric e+e− collider, to be built near the INFN National Frascati Laboratory in Italy, has been designed to deliver a luminosity greater than 1036 cm−2 s−1 with moderate beam currents and a reduced center of mass boost with respect to earlier B-Factories. An improved vertex resolution is required for precise time-dependent measurements and the SuperB Silicon Vertex Tracker will be equipped with an innermost layer of small radius (about 1.5 cm), resolution of 10–15μm in both coordinates, low material budget (<1% X0), and able to withstand a background rate of several tens of MHz/cm2. The ambitious goal of designing a thin pixel device with these stringent requirements is being pursued with specific R&D programs on different technologies: hybrid pixels, CMOS MAPS and pixel sensors developed with vertical integration technology. The latest results on the various pixel options for the SuperB SVT will be presented.

The PixFEL project aims to develop an advanced X-ray camera for imaging suited for the demanding requirements of next generation free electron laser (FEL) facilities. New technologies can be deployed to boost the performance of imaging detectors as well as future pixel devices for tracking. In the first phase of the PixFEL project, approved by the INFN, the focus will be on the development of the microelectronic building blocks, carried out with a 65 nm CMOS technology, implementing a low noise analog front-end channel with high dynamic range and compression features, a low power ADC and high density memory. At the same time PixFEL will investigate and implement some of the enabling technologies to assembly a seamless large area X-ray camera composed by a matrix of multilayer four-side buttable tiles. A pixel matrix with active edge will be developed to minimize the dead area of the sensor layer. Vertical interconnection of two CMOS tiers will be explored to build a four-side buttable readout chip with small pixel pitch and all the on-board required functionalities. The ambitious target requirements of the new pixel device are: single photon resolution, 1 to 104 photons @ 1 keV to 10 keV input dynamic range, 10-bit analog to digital conversion up to 5 MHz, 1 kevent in-pixel memory and 100 μm pixel pitch. The long term goal of PixFEL will be the development of a versatile X-ray camera to be operated either in burst mode (European XFEL), or in continuous mode to cope with the high frame rates foreseen for the upgrade phase of the LCLS-II at SLAC.

CVD diamond radiation sensors are being developed for possible use in trackers in the LHC experiments. The diamond promises to be radiation hard well beyond particle fluences that can be tolerated by Si sensors. Recent results from the RD 42 collaboration on charge collection distance and on radiation hardness of CVD diamond samples will be reported. Measurements with diamond tracking devices, both strip detectors and pixel detectors, will be discussed. Results from beam tests using a diamond strip detector which was read out with fast, 25 ns shaping time, radiation-hard pipeline electronics will be presented.

This paper presents the results of the experimental characterization of the channel thermal noise in MOSFETs belonging to a submicron gate process, with minimum gate length L=0.35 /spl mu/m. The data are compared with a noise model taking into account short-channel effects such as velocity saturation and hot carriers. The contribution of gate and substrate parasitic resistors is also evaluated and included in the model. The analysis is carried out for devices with various gate geometries, investigating the behavior of the noise-related parameters in the range of small gate-to-source overdrive voltages, which is of major concern for low-power circuits.

The slow component of the output pulse of Semi-Insulating (SI) Gallium Arsenide (GaAs) particle detectors, which affects charge collection efficiency (cce), has been generally attributed to trapping/detrapping effects. However, most of the detectors analyzed in the literature can only be operated below the voltage V/sub d/ necessary to extend the electric field all the way to the ohmic contact, making difficult to distinguish between the effect of the non-active part of the detector and that of trapping/detrapping. To do that, we have carefully analyzed the output signals of SI GaAs detectors, operated below and above V/sub d/ and irradiated with /sup 241/Am /spl alpha/ particles. When the detector is biased below V/sub d/ the output signals are affected also by the non-active part of the detector itself, while, when the detector is operated above V/sub d/, the output signals are only affected by trapping/detrapping of charge carriers. We found that trapping/detrapping is only relevant for the hole contribution to the signal. Trapping/detrapping effects are in agreement with the characteristics of deep levels present in the detectors as analyzed by means of PICTS (Photo Induced Current Transient Spectroscopy) and P-DLTS (Photo Deep Level Transient Spectroscopy).

The microstrip vertex detector in BaBar experiment will be read out by a purposely designed front-end chip. The chip performs amplification and analog-to-digital conversion to retain the information of the charge induced on the readout strips. It stores the digital data during the trigger latency time and associates the incoming trigger with the relevant hit data. Data are buffered and sent off in sparsified form when a readout command is received. The present paper discusses the signal processing performed by the chip.

While the CMOS version of the front-end chip developed for the microstrip vertex detector of the Aleph experiment is ready to go into operation, a new development is being carried on to achieve a reduction in noise. The improvement is related to the use of a JFET-CMOS chip design which is described in the present paper.

Submicron CMOS technologies provide well-established solutions to the implementation of low noise front-end electronics for a wide range of detector applications. In recent years high performance mixed signal circuits were fabricated in 0.35 mum and 0.25 mum processes. Presently the IC designers' effort is gradually shifting to 0.13 mum technologies, following the trend of commercial silicon foundries. Since commercial CMOS processes maintain a steady trend in device scaling, it is essential to monitor the impact of these technological advances on the noise parameters of the devices. To estimate the noise limits of a front-end system in the 0.13 mum node, this work presents the results of noise measurements carried out on NMOS and PMOS devices in two commercial processes from different foundries. The behavior of the 1/f and white noise terms is studied as a function of the device polarity and of the gate length and width to account for different detector requirements. The study is focused on low current density applications where devices are biased in weak or moderate inversion. Data obtained from the measurements provide a powerful tool to model noise parameters and establish front-end design criteria in a 0.13 mum CMOS process

This work is concerned with the design of time invariant analog circuits for processing the signals from deep N-well monolithic CMOS sensors. As compared to the three-transistor front-end typically used in imaging applications, the schemes proposed here, which were conceived to be included in a binary readout channel, lend themselves to pixel-level sparsified readout and are expected to be capable of managing the large flow of data anticipated for the future high luminosity colliding machines while obeying quite severe material budget requirements. Various solutions complying with different power dissipation and point resolution constraints have been implemented in a 130 nm CMOS technology, paying particular attention to equivalent noise charge and threshold dispersion performance. This paper intends to describe and compare the features of the different approaches by means of simulations, experimental results and theoretical analysis.

We report on further developments of our recently proposed design approach for a full in-pixel signal processing chain of deep n-well (DNW) MAPS sensors, by exploiting the triple well option of a CMOS 0.13 μm process. The optimization of the collecting electrode geometry and the re-design of the analog circuit to decrease power consumption have been implemented in two versions of the APSEL chip series, namely “APSEL3T1” and “APSEL3T2”. The results of the characterization of 3x3 pixel matrices with full analog output with photons from <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">55</sup> Fe and electrons from <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">90</sup> Sr are described. Pixel equivalent noise charge (ENC) of 46 e- and 36 e- have been measured for the two versions of the front-end implemented toghether with signal-to-noise ratios between 20 and 30 for Minimum Ionizing Particles. In order to fully exploit the readout capabilities of our MAPS, a dedicated fast readout architecture performing on-chip data sparsification and providing the timing information for the hits has been implemented in the prototype chip “APSEL4D”, having 4096 pixels. The criteria followed in the design of the readout architecture are reviewed. The implemented readout architecture is data-driven and scalable to chips larger than the current one, which has 32 rows and 128 columns. Tests concerning the functional characterization of the chip and response to radioactive sources have shown encouraging preliminary results. A successful beam test took place in September 2008. Preliminary measurements of the APSEL4D charge collection efficiency and resolution confirmed the DNW device is working well. Moreover the data driven approach of the readout chips has been successfully used to demonstrate the possibility to build a Level 1 trigger system based on Associative Memories.

The SuperB asymmetric e+–e- collider has been designed to deliver a luminosity greater than 1036cm-2s-1 with moderate beam currents. Comparing to current B-Factories, the reduced center of mass boost of the SuperB machine requires improved vertex resolution to allow precision measurements sensitive to New Physics. We present the conceptual design of the silicon vertex tracker (SVT) for the SuperB detector with the present status of the R&D on the different options under study for its innermost Layer0.

Deep N-well (DNW) CMOS monolithic active pixel sensors (MAPS) fabricated in a 130 nm technology have been exposed to γ-rays up to an integrated dose of about 10 Mrad and subjected to a 100 °C/168 h annealing cycle. Device tolerance to total ionizing dose has been evaluated by monitoring the change in charge sensitivity, noise and charge collection properties after each step of the irradiation and annealing campaign. Damage mechanisms and their relation to front-end architecture and sensor features are thoroughly discussed by comparing the response to ionizing radiation of different test structures and based on radiation induced degradation models in single MOS transistors.

This work is concerned with the study of the analog properties of MOSFET devices belonging to a 65 nm CMOS technology with emphasis on intrinsic voltage gain and noise performance. This node appears to be a robust and promising solution to cope with the unprecedented requirements set by silicon vertex trackers in experiments upgrades and future colliders as well as by imaging detectors at light sources and free electron lasers. In this scaled-down technology, the impact of new dielectric materials and processing techniques on the analog behavior of MOSFETs has to be carefully evaluated. An inversion level design methodology has been adopted to analyze data obtained from device measurements and provide a powerful tool to establish design criteria for detector front-ends in this nanoscale CMOS process. A comparison with data coming from less scaled technologies, such as 90 nm and 130 nm nodes, is also provided and can be used to evaluate the resolution limits achievable for low-noise charge sensitive amplifiers in the 100 nm minimum feature size range.

This report reviews current trends in the R&D of semiconductor pixellated sensors for vertex tracking and radiation imaging. It identifies requirements of future HEP experiments at colliders, needed technological breakthroughs and highlights the relation to radiation detection and imaging applications in other fields of science.

This work is meant to explore the limitations in the design of threshold discriminators employed as the final stage of the analog chain processing the signals from particle tracking pixellated detectors. The 65 nm CMOS technology, which is currently under scrutiny of the electronic designers in the high energy physics community, is the natural choice for this study. In the design of the discriminators, power dissipation, area, delay, delay dispersion and threshold dispersion (input offset), while calling for fairly different, sometimes opposite design choices, have to be concurrently optimized, in compliance with the specifications set by the application. For the purpose of investigating the boundaries set by the technology, a couple of different simple architectures have been studied and optimized under different parameter configurations. The paper will provide a set of rules for the constrained design of threshold discriminators in multichannel front-end chips for pixel detectors.

This work is focused on the design and the experimental characterization of an analog channel developed for the readout of lithium-drifted silicon detectors of the General AntiParticle Spectrometer (GAPS) experiment aimed at the search for dark matter. The instrument is designed for the identification of antideuteron particles from cosmic rays during an Antarctic balloon mission scheduled for late 2022. A low-noise analog front-end, featuring a dynamic signal compression to comply with the wide input range, has been designed in commercial 180-nm CMOS technology. The channel was fabricated in 2018 and is the first building block toward the development of a multichannel readout ASIC. The article will provide a description of the design criteria, the architecture of the channel, and a summary of the results of the experimental characterization.

In future HEP accelerators, such as the LHC (CERN), detectors and electronics in the vertex region of the experiments will suffer from extreme radiation. Thus radiation hardness is required for both detectors and electronics to survive in this harsh environment. CVD diamond, which is investigated by the RD42 Collaboration at CERN, can meet these requirements. Samples of up to 2×4cm2 have been grown and refined for better charge collection properties, which are measured with a β source or in a testbeam. A large number of diamond samples has been irradiated with hadrons to fluences of up to 5×1015cm−2 to study the effects of radiation. Both strip and pixel detectors were prepared in various geometries. Samples with strip metallization have been tested with both slow and fast readout electronics, and the first diamond pixel detector proved fully functional with LHC electronics.

Effects determining the energy and spatial resolution of a calorimeter based on liquid krypton have been studied. With cathode strips of 10 mm a spatial resolution of 0.4 mm has been obtained in a cosmic rays test. The energy resolution of the calorimeter (0.4 ton of krypton) has been measured with positrons, achieving a rms of 5.7% at E = 130 MeV and 1.7% at E = 1200 MeV. The measurements are compared to Monte Carlo simulations.

Submicrometer CMOS technologies provide well-established solutions to the implementation of low-noise front-end electronics for a wide range of detector applications. Since commercial CMOS processes maintain a steady trend in device scaling, it is essential to monitor the impact of these technological advances on the noise parameters of the devices. In this paper we present the results of an extensive analysis carried out on CMOS transistors fabricated in 0.35, 0.25, and 0.18 mum technologies from different foundries. This allows us to evaluate the behavior of 1/f and channel thermal noise parameters with different gate oxide thickness and minimum channel length and to give an estimate of their process-to-process spread. The experimental analysis is focused on actual device operating conditions in monolithic detector readout systems. This means that moderate or weak inversion are often the only relevant regions for front-end devices. To account for different detector requirements, the noise behavior of devices with different geometries and input capacitance was investigated. The large set of data gathered from the measurements provides a powerful tool to model noise parameters and establish front-end design criteria in deep submicrometer CMOS processes

A prototype of a mixed-mode ASIC composed of a fast readout architecture that interfaces with a matrix of 4096 Monolithic Active Pixel Sensor (MAPS) was fabricated via STM 130 nm CMOS technology. Groups of 4×4 pixels form a macro-pixel (MP). The readout architecture is parallel and could overcome the readout speed limit of big matrices. As the output port can only accept one-hit information at a time, an internal queuing system has been provided to face high hit-rate conditions. The ASIC can work in two different manners as it can be connected to an actual full-custom matrix of MAPS or to a digital matrix emulator composed of standard cells, for testing facilities. For both operating modes a slow-control phase is required to load the chip configuration. Previous versions of similar ASICs were designed and tested. The work is aimed at improving the design of MAPS detectors with an on-chip fast sparsification system, for particle tracking, to match the requirements of future high-energy physics experiments. The readout architecture implemented is data driven extending the flexibility of the system to be also used in first level triggers on tracks in vertex detectors. Preliminary simulations and tests indicate that the readout system can cope with an average hit-rate up to 100 MHz/cm2 if a master clock of 80 MHz is used, while maintaining an overall efficiency over 99%.

This paper is devoted to the study of total ionizing dose effects in deep N-well (DNW) CMOS monolithic active pixel sensors (MAPS) for particle tracking fabricated in a STMicroelectronics 130 nm process. DNW-MAPS samples were exposed to gamma-rays up to a final dose of 1100 krad(SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) and then subjected to a 100degC annealing cycle. Ionizing radiation tolerance was tested by monitoring the device noise properties and its response to charge injection through an external pulse generator throughout the irradiation and annealing campaign. The origins of performance degradation are discussed based on the results from radiation hardness characterization of single transistors belonging to the same CMOS technology and of test diodes reproducing the MAPS collecting electrode structure. Also circuit simulations have been performed to supply further evidence for the proposed degradation mechanisms.

The paper presents the development of a compact system able to measure sweat pH, by means of a functionalized textile and a color sensor, and the skin temperature. The aim is to achieve a wearable miniaturized system capable to estimate the body hydration level during exercise or a heat stress. Potential users span from elderly, first responders to athletes. The system has been characterized in the laboratory by using buffer solution, artificial sweat, and an oven for temperature sensor calibrations. Preliminary on-body trials are also reported in the final part of the paper.

The PixFEL project is conceived as the first stage of a long term research program aiming at the development of advanced X-ray imaging instrumentation for applications at the free electron laser (FEL) facilities. The project aims at substantially advancing the state-of-the-art in the field of 2D X-ray imaging by exploring cutting-edge solutions for sensor development, for integration processes and for readout channel architectures. The main focus is on the development of the fundamental microelectronic building blocks for detector readout and on the technologies for the assembly of a multilayer module with minimum dead area. This work serves the purpose of introducing the main features of the project, together with the simulation results leading to the first prototyping run.

The objective of this work is to design a high performance bandgap voltage reference circuit in a standard commercial 65 nm CMOS technology capable of operating in harsh radiation environments. A prototype circuit based on three different devices (diode, bipolar transistor and MOSFET) was fabricated and tested. Measurement results show a temperature variation as low as ±3.4 mV over a temperature range of 170 ° C (−30 °C to 140 °C) and a line regulation at room temperature of 5.2%/V. Measured VREF is 690 mV±15 mV (3σ) for 26 samples on the same wafer. Circuits correctly operate with supply voltages in the range from 1.32 V down to 0.78 V. A reference voltage shift of only 7.6 mV (around 1.1%) was measured after irradiation with 10 keV X-rays up to an integrated dose of 225 Mrad (SiO2).

This paper reports the design and experimental results from the characterization of an integrated circuit developed for the readout of the X-ray spectrometer and tracking system of the General AntiParticle Spectrometer (GAPS) balloon mission. GAPS will search for an indirect signature of dark matter through the detection of low-energy (<0.25 GeV/n) cosmic-ray antiprotons, antideuterons and antihelium nuclei. The ASIC, named SLIDER32 (32 channels Si-LI DEtector Readout ASIC), was fabricated in a 180 nm CMOS technology and is comprised of 32 analog readout channels, an 11-bit SAR ADC and a digital back-end section which is responsible for defining channel settings and for sending digital information to the data acquisition system. The core of the ASIC is a low-noise analog channel implementing a dynamic signal compression which makes the chip suitable for resolving both X-rays in the range of 20 to 100 keV and charged particles with energy deposition of up to 100 MeV. It features an energy resolution of 4 keV FWHM in the 20–100 keV range with a 40 pF detector capacitance, to clearly distinguish X-rays from antiprotonic or antideuteronic exotic atoms. The readout electronics of the ASIC will run at a temperature of about –40 °C, complying with a detector leakage current of the order of 5–10 nA per strip.

The General Antiparticle Spectrometer (GAPS) Antarctic long duration balloon mission is scheduled for launch during the austral summer of 2024-25.Its novel detection technique, based on exotic atom formation, excitation, and decay, is specifically designed for the detection of slow moving cosmic antiprotons and antideuterons.Such antinuclei are predicted by a wide variety of allowed dark matter models, as well as other astrophysical theories like primordial black holes.There are two main components of the GAPS instrument: a large-area tracker and a surrounding time-of-flight system (TOF).The combination of these two systems allows GAPS to effectively differentiate between species of negatively-charged antinuclei and determine the energy deposition, velocity, and trajectory of particles interacting with the detector.This contribution will focus on the TOF, which determines the velocity of the incoming antiparticle and provides the trigger to the experiment.We will give an overview of the TOF detector, an explanation of relevant electronics, and a report on its construction and preliminary performance.The TOF is composed of 160 thin plastic scintillator paddles ranging in length from 1.5 to 1.8 meters.At each paddle end, signals from six silicon photomultipliers are combined to produce two copies of the resulting waveform: one to form the trigger and one for data readout.This design is optimized for low mass and fast data acquisition while still maintaining good light collection.

A bstract The first measurement of the top quark pair ( $$ \textrm{t}\overline{\textrm{t}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>t</mml:mi> <mml:mover> <mml:mi>t</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> ) production cross section in proton-proton collisions at $$ \sqrt{s} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 13 . 6 TeV is presented. Data recorded with the CMS detector at the CERN LHC in Summer 2022, corresponding to an integrated luminosity of 1 . 21 fb − 1 , are analyzed. Events are selected with one or two charged leptons (electrons or muons) and additional jets. A maximum likelihood fit is performed in event categories defined by the number and flavors of the leptons, the number of jets, and the number of jets identified as originating from b quarks. An inclusive $$ \textrm{t}\overline{\textrm{t}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>t</mml:mi> <mml:mover> <mml:mi>t</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> production cross section of 881 ± 23 (stat + syst) ± 20 (lumi) pb is measured, in agreement with the standard model prediction of $$ {924}_{-40}^{+32} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>924</mml:mn> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>40</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>32</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> pb.

Quasireal photons exchanged in relativistic heavy ion interactions are powerful probes of the gluonic structure of nuclei. The coherent J/ψ photoproduction cross section in ultraperipheral lead-lead collisions is measured as a function of photon-nucleus center-of-mass energies per nucleon (WγNPb) over a wide range of 40<WγNPb<400 GeV. Results are obtained using data at the nucleon-nucleon center-of-mass energy of 5.02 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 1.52 nb−1. The cross section is observed to rise rapidly at low WγNPb, and plateau above WγNPb≈40 GeV, up to 400 GeV, entering a new regime of small Bjorken-x (≈6×10−5) gluons being probed in a heavy nucleus. The observed energy dependence is not predicted by current quantum chromodynamic models.Received 29 March 2023Revised 17 August 2023Accepted 26 October 2023DOI:https://doi.org/10.1103/PhysRevLett.131.262301Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.© 2023 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Research AreasPhoton productionRelativistic heavy-ion collisionsPhysical SystemsGluonsTechniquesHadron collidersParticles & FieldsNuclear Physics

Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98% of the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 μm was observed, consistent with expectations given the detector pitch.

We report on an research and development activity aimed at the fabrication of silicon microstrip detectors with integrated front-end electronics to be used in high-energy physics and space experiments and medical/industrial imaging applications. A specially tailored fabrication technology has been developed at ITC-IRST (Trento, Italy), which allows for the production of single-sided microstrip detectors, with integrated coupling capacitors and polysilicon resistors, as well as active devices, including N-channel junction field effect transistors and N- or P-channel MOS transistors. The main characteristics of the fabrication process are outlined. Experimental results from the electrical characterization of the devices are reported, showing that transistors with good electrical figures can be obtained within the proposed technology while preserving the basic detector parameters.

A different approach to the design of CMOS MAPS has recently been proposed. By exploiting the triple well option of a CMOS commercial process, a deep n-well (DNW) MAPS sensor has been realized with a full in-pixel signal processing chain: charge preamplifier, shaper, discriminator and a latch. This readout approach beeing compatible with data sparsification will improve the readout speed potential of MAPS sensors. The first protoype chips, realized with STMicroelectronics 130 nm triple well process, proved the new design proposed for DNW MAPS is viable with a good sensitivity to photons from <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">55</sup> Fe and electrons from <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">90</sup> Sr. Extensive tests performed to characterize the second generation of the APSEL chips based on the DNW MAPS design are reported. Small 3times3 pixel matrices with full analog output have been tested with radioactive sources to characterize charge collection. Pixel noise equivalent charge (ENC) of 50 e <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> and signal-to-noise ratio for MIPs of about 14 have been measured. Improved pixel noise and reduced threshold dispersion (about 100 e <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> ) have been measured in the 8times8 matrix with a sequential readout. Based on the new DNW MAPS design a dedicated fast readout architecture to perform on-chip data sparsification is currently under development. The aim is to incorporate in the same detector the advantages of the thin CMOS sensors and similar functionalities as in hybrid pixels.

High energy physics experiments at future particle accelerators set very demanding requirements on the performance of sensors and readout electronics. In these applications, silicon pixel detectors have to integrate advanced functionalities in the pixel cell itself, such as amplification, filtering, discrimination, time stamping, zero suppression and analog-to-digital conversion. This paper discusses how 3D vertical integration has the potential of providing a performance breakthrough in particle detection systems, and how the high energy physics community is organizing itself to meet the challenges of designing and fabricating vertically integrated devices.

We propose a new detector system capable to fulfil the requirements of the future XFEL in Hamburg. The instrument will be able to record X-ray images with a maximum frame rate of 5MHz and to achieve a high dynamic range. The system is based on a pixel-silicon sensor with a new designed non-linear-DEPFET as a central amplifier structure. The detector chip is bump-bonded to a set of mixed signal readout ASICs that provide full parallel readout. The signals coming from the detector, after having been processed by an analog filter, are immediately digitized by a series of 8-ENOB ADCs and locally stored in a custom designed memory also integrated in the ASICs designed in the 130nm CMOS technology. During the time gap of 99ms of the XFEL machine, the digital data are sent off the focal plane to a DAQ electronics that acts as an interface to the back-end of the whole instrument. The pixel sensor has been designed so as to combine high energy resolution at low signal charge with high dynamic range. This has been motivated by the desire to be able to be sensitive to single low energy photons and, at the same time, to measure at other positions of the detector signals corresponding to up to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> photons of 1keV. In order to fit this dynamic range into a reasonable output signal swing, achieving at the same time single photon resolution, a strongly non linear characteristics is required. The new proposed DEPFET provides the required dynamic range compression at the sensor level, considerably facilitating the task of the electronics. At the same time the DEPFET charge handling capacitance is enormously increased with respect to standard DEPFETs. The Pixel matrix will have a format of 1024×1024 with a pixel size of 200×200 µm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .