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In this study, a test beam model of negative moment region was designed to study its deflection characteristics under over-limit static load and variable amplitude cyclic load scenarios. (1) According to the deflection test results of the test beam under over-limit static load, the load-deflection curve under static load before and after 10000 times of over-limit fatigue load tended to sharply increase in the first place and then slow down afterwards. At the ultimate load, the maximum deflection value of the two was 8.625 mm and 8.76 mm, respectively. The maximum deflection value after 10000 times of over-limit fatigue load increased by 1.57% compared with that before. (2) The deflection test results of the test beam under variable amplitude cyclic load showed that both the total deflection and the residual deflection percentage increased firstly and decreased with the increasing fatigue load times. The total deflection ranged from 4.07–4.3 mm, and the residual deflection percentage was 0.1–1.65%; The residual deflection percentage reached a maximum of 1.65% when the fatigue load times reached 2 million. (3) The deflection test results of the test beam under over-limit variable amplitude fatigue load showed that the maximum residual deflection reached 0.08 mm (maximum residual deflection percentage 1.75%), 0.11 mm (maximum residual deflection percentage 2.30%), 0.16 mm (maximum residual deflection percentage 2.65%) after 1.5, 2 and 3 times over-limit variable amplitude fatigue load was imposed respectively. The maximum deflection did not fluctuate obviously, indicating that the test beam was had sound working performance. (4) In this study, the shear stiffness and fatigue load times were fully considered, the mean value of the ratio of the deformation value to the measured value of the test beam was 0.89, and the standard deviation was 4.86%. When the fatigue load times exceeded 2.8 million, the ratio of the calculated value to the measured value was less than 0.85. In conclusion, the model had its own limitations. [ABSTRACT FROM AUTHOR]

The HL-LHC necessitates a Phase-2 upgrade for the CMS detector, which includes the complete replacement of the existing tracker. The new Outer Tracker incorporates two types of silicon module, 2S and PS, based on an innovative transverse momentum (pT) discrimination idea. By using these modules, the information from the tracker will be sent to the Level-1 (L1) trigger for the first time. They will identify charged particles with pT > 2 GeV, helping to reduce the data sent to the L1 trigger. This paper offers a comprehensive overview of the 2S module prototyping process, which include the precise assembly and testing procedures to ensure their performance and quality before integration into the Outer Tracker. Additionally, to assess the performance of a 2S module in beam, the data from a DESY test beam is reconstructed and analyzed using the Corryvreckan offline reconstruction framework. The results demonstrate agreement to within 1% with those obtained using the EUTelescope framework. [ABSTRACT FROM AUTHOR]

In high-energy physics, there is a need to investigate alternative silicon sensor concepts that offer cost-efficient, large-area coverage. Sensors based on CMOS imaging technology present such a silicon sensor concept for tracking detectors. The CMOS Strips project investigates passive CMOS strip sensors fabricated by LFoundry in a 150 nm technology. By employing the technique of stitching, two different strip sensor formats have been realised. The sensor performance is characterised based on measurements at the DESY II Test Beam Facility. The sensor response was simulated utilising Monte Carlo methods and electric fields provided by TCAD device simulations. This study shows that employing the stitching technique does not affect the hit detection efficiency. A first look at the electric field within the sensor and its impact on generated charge carriers is being discussed. [ABSTRACT FROM AUTHOR]

The upcoming High-Luminosity running phase of the LHC will require a complete replacement of the current tracking system in the CMS experiment. With the planned integrated luminosity of up to 4000 fb−1 to be delivered to the experiments, the innermost layers of the CMS Inner Tracker (IT) will face particle fluences of up to a non-ionizing energy loss (NIEL) of Φ eq = 3.5 × 1016 cm−2. Through an extensive R&D program involving multiple vendors, several pixel sensor options have been thoroughly evaluated, considering different pixel pitches and sensor cell designs. Recently, the final choices have been made. All layers, except the innermost layer of the barrel section of the IT, will be equipped with planar n-in-p sensors featuring an active thickness of 150 μ m and pixel pitches of 25 × 100 μ m 2. During the initial phase of the sensor qualification campaign, the sensors were coupled with demonstrator chips (RD53A), and the modules were exposed to fluences of up to Φ eq = 2.0 × 1016 cm−2, undergoing comprehensive testing at both CERN and DESY test beam facilities. In 2023, single chip assemblies, along with the first full modules incorporating the final, full-size prototype readout chip (RD53B-CMS) irradiated up to Φ eq = 1.0 × 1016 cm−2, have become available and were tested at DESY. In this article, an overview of the preliminary test beam results will be provided. The studies will cover hit efficiency, spatial resolution, and noise hit occupancy for both non-irradiated samples and irradiated assemblies. The preliminary findings are in line with previous results obtained with RD53A assemblies. The measurements described in this contribution paved the way for the submission of the final readout chip and kickoff batches for planar production sensors for the Inner Tracker that have been launched recently. [ABSTRACT FROM AUTHOR]

Silicon Photomultipliers (SiPMs) are state-of-the-art photon detectors used in particle physics, medical imaging, and beyond. They are sensitive to individual photons in the optical wavelength regime and achieve time resolutions of a few tens of picoseconds, which makes them interesting candidates for timing detectors in tracking systems for particle physics experiments. The Geiger discharges triggered in the sensitive elements of a SiPM, Single-Photon Avalanche Diodes (SPADs), yield signal amplitudes independent of the energy deposited by a photon or ionizing particle. This intrinsically digital nature of the signal motivates its digitization already on SPAD level. A digital SiPM (dSiPM) was designed at Deutsches Elektronen Synchrotron (DESY), combining a SPAD array with embedded CMOS circuitry for on-chip signal processing. A key feature of the DESY dSiPM is its capability to provide hit-position information on pixel level, and one hit time stamp per quadrant at a 3 MHz readout-frame rate. The pixels comprise four SPADs and have a pitch of about 70 μm. The four time stamps are provided by 12 bit Time-to-Digital Converters (TDCs) with a resolution better than 100 ps. The chip was characterized in the laboratory to determine dark count rate, breakdown voltage, and TDC characteristics. Test-beam measurements are analyzed to assess the DESY dSiPMs performance in the context of a 4D-tracking applications. The results demonstrate a spatial hit resolution on a pixel level, a minimum-ionizing particle detection efficiency of about 30 % and a time resolution in the order of 50 ps. [ABSTRACT FROM AUTHOR]

The High Granularity Timing Detector (HGTD) is designed for the mitigation of pile-up effects in the ATLAS forward region and for bunch per bunch luminosity measurements. HGTD, based on Low Gain Avalanche Detector (LGAD) technology and covering the pseudorapidity region between 2.4 and 4.0, will provide high precision timing information to distinguish between collisions occurring close in space but well-separated in time. Apart from being radiation resistant, LGAD sensors should deliver 30 ps time resolution per track for a minimum-ionizing particle (35 ps per hit) at the start of lifetime, increasing to 50 ps per track (70 ps per hit) at the end of HL-LHC operation. Each readout cell has a transverse size of 1.3×1.3 mm 2 leading to a highly granular detector with about 3 millions of readout electronics channels. A dedicated ASIC for the HGTD detector, ALTIROC, is being developed in several phases producing prototype versions of 2×2, 5×5 and 15×15 channels. HGTD modules are hybrids of the LGAD and ALTIROC connected through flip-chip bump bonding process. Several test beam campaigns have been conducted at DESY and CERN SPS between 2021 and 2022. A summary of the results from LGAD-alone and hybrids will be presented. [ABSTRACT FROM AUTHOR]

The High Luminosity upgrade of Large Hadron Collider (HL-LHC) will increase the LHC luminosity and with it the density of particles on the detector by an order of magnitude. For protecting the inner silicon detectors of the ATLAS experiment and for monitoring the delivered luminosity, a radiation hard beam monitor was developed based on polycrystalline Chemical Vapor Deposition (pCVD) diamond detectors and a new dedicated rad-hard front-end ASIC. Due to the large range of particle flux through the detector, flexibility is very important. To satisfy the requirements imposed by the HL-LHC, our solution is based on segmenting diamond sensors into devices of varying size and reading them out with new multichannel readout ASICs divided into two independent parts — each of them serving one of the tasks of the system. This paper describes the system design including detectors, electronics, mechanics and services and presents preliminary results from the most recent detectors fabricated, using our prototype ASIC with data from beam tests at CERN. [ABSTRACT FROM AUTHOR]

The Mu2e experiment at Fermilab will search for the charged-lepton flavor violating neutrino-less conversion of a negative muon into an electron in the field of an aluminum nucleus. The calorimeter plays an important role in providing a fast trigger filter, excellent particle identification and a seeding for track reconstruction. Its requirements are to provide an energy (timing) resolution better than 10% (0.5 ns) and a position resolution below 1 cm, for 100 MeV electrons. The calorimeter consists of two disks, each one made of 674 un-doped CsI crystals readout by two large area arrays of 2 × 3 UV-extended SiPMs of 6 × 6 mm 2 dimensions. A large scale prototype (Module-0) has been constructed and tested with an electron beam in the energy range between 60 and 120 MeV at the BTF of Frascati National Laboratories. Results demonstrated that this calorimeter satisfies the Mu2e requirements. [ABSTRACT FROM AUTHOR]

Abstract An upgrade program is underway to increase the luminosity of the LHC up to about 7.5 × 1034 cm−2s−1 in 2027, with the goal of an integrated luminosity of 3000 fb−1 by the end of 2037. This High Luminosity scenario, HL-LHC, presents new challenges of higher data rates and increased radiation hardness for the pixel detector: a non-ionizing fluence of 2.3 × 1016 n e q /cm2 an ionizing dose of 12 MGy, is expected on the inner pixel layer for 3000 fb−1 integrated luminosity. To maintain or even improve the performance of the present system, new technologies have to be fully exploited for the so-called Phase-II upgrade. Among them is the future version of front-end chips in 65-nm CMOS by the CERN RD53 Collaboration which supports small pixel sizes of 50 × 50 or 25 × 100 μ m2 lower thresholds (∼ 1000 e −). For the development of the appropriate planar pixel sensor, CMS has recently launched a submission of n + -p sensors on 6 inch wafers with an active thickness of 150 μ m at Hamamatsu. The submission consists of physically thinned, directly bonded and deep diffused wafers with p-stop or p-spray isolation. A variety of sensors with and without biasing scheme is designed to match the different read-out chips (RD53A, ROC4Sens, etc.) and first hybrid modules are assembled at Fraunhofer IZM. In this document, we will present an overview of the Phase II pixel R&D program and report on preliminary results on the HPK submission. [ABSTRACT FROM AUTHOR]

Abstract DESY Hamburg operates a test beam facility with three independent beam lines at the DESY II synchrotron. It is world-wide one of very few facilities providing test beams in the GeV range. To this end, it offers electron/positron beams with user-selectable momenta from 1-6 GeV/c. The available infrastructure for the users is unique, including a high field solenoidal magnet and permanently installed high-precision pixel beam telescopes. This publication gives a detailed description of the facility, the available infrastructure, and the simulated and measured performance. [ABSTRACT FROM AUTHOR]

In this paper we report measurements of the uniformity of time resolution, signal amplitude, and charged particle detection efficiency across the sensor surface of low-gain avalanche detectors (LGAD). Comparisons of the performance of sensors with different doping concentrations and different active thicknesses are presented, as well as their temperature dependence and radiation tolerance up to 6 × 1 0 14 n/cm 2 . Results were obtained at the Fermilab test beam facility using 120 GeV proton beams, and a high precision pixel tracking detector. LGAD sensors manufactured by the Centro Nacional de Microelectrónica (CNM) and Hamamatsu Photonics (HPK) were studied. The uniformity of the sensor response in pulse height before irradiation was found to have a 2% spread. The signal detection efficiency and timing resolution in the sensitive areas before irradiation were found to be 100% and 30–40 ps, respectively. A “no-response” area between pads was measured to be about 130 μ m for CNM and 170 μ m for HPK sensors. After a neutron fluence of 6 × 1 0 14 n/cm 2 the CNM sensor exhibits a large gain variation of up to a factor of 2.5 when comparing metalized and non-metalized sensor areas. An irradiated CNM sensor achieved a time resolution of 30 ps for the metalized area and 40 ps for the non-metalized area, while a HPK sensor irradiated to the same fluence achieved a 30 ps time resolution. [ABSTRACT FROM AUTHOR]

Beam diagnostics are crucial for smooth accelerator operations. Many techniques rely on instrumentation in which the beam properties are significantly affected by the measurement. Novel approaches aim to use Cherenkov Diffraction Radiation (ChDR) for non-invasive diagnostics. Unlike regular Cherenkov Radiation, the charged particles do not have to move inside of the medium, but it is sufficient for them to move in its vicinity as long as they are faster than the speed of light in the medium. Changes to the beam properties due to ChDR measurements are consequently negligible. To examine ChDR emission under different conditions, we placed a fused silica radiator in the DESY II Test Beam. We observed increases in ChDR intensity for electron and positron momenta between 1 GeV c −1 and 5 GeV c −1 . Additionally, we found a larger photon yield for electrons than positrons for increasing particle momenta. However, the significance of these measurements is strongly limited by the accuracy of the conversion from the measured signal to absolute photon numbers. The results suggest a need for further research into the ChDR generation by electrons and positrons and may find application in the design of future beam diagnostic devices. [ABSTRACT FROM AUTHOR]

Test beam facilities are essential to study the response of novel detectors to particles. At the DESY II Test Beam facility, users can test their detectors with an electron beam with a momentum from 1–6 GeV. To track the beam particles, EUDET-style telescopes are provided in each beam area. They provide excellent spatial resolution, but the time resolution is limited by the rolling shutter architecture to a precision of approximately 230 μ s. Since the demand on particle rates – and hence track multiplicities – is increasing timing is becoming more relevant. DESY foresees several upgrades of the telescopes. TelePix is an upgrade project to provide track timestamping with a precision of better than 5 ns and a configurable region of interest to trigger the telescope readout. Small scale prototypes have been characterized in laboratory and test beam measurements. Laboratory tests with an injection corresponding to 2300 electrons show a S/N of above 20. Test beam characterization shows efficiencies of above 99% over a threshold range of more than 100 mV and time resolutions of 2.4 ns at low noise rates. [ABSTRACT FROM AUTHOR]

The CMS Binary Chip (CBC) is a prototype version of the front-end read-out ASIC to be used in the silicon strip modules of the CMS outer tracking detector during the high luminosity phase of the LHC. The CBC is produced in 130 nm CMOS technology and bump-bonded to the hybrid of a double layer silicon strip module, the so-called 2S- p T module. It has 254 input channels and is designed to provide on-board trigger information to the first level trigger system of CMS, with the capability of cluster-width discrimination and high- p T track identification. In November 2013 the first 2S- p T module prototypes equipped with the CBC chips were put to test at the DESY-II test beam facility. Data were collected exploiting a beam of positrons with an energy ranging from 2 to 4 GeV. In this paper the test setup and the results are presented. [ABSTRACT FROM AUTHOR]

A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip. [ABSTRACT FROM AUTHOR]

An all silicon pixel telescope has been assembled and used at the Fermilab Test Beam Facility (FTBF) since 2009 to provide precise tracking information for different test beam experiments with a wide range of Detectors Under Test (DUTs) requiring high resolution measurement of the track impact point. The telescope is based on CMS pixel modules left over from the CMS forward pixel production. Eight planes are arranged to achieve a resolution of less than 8 μm on the 120 GeV proton beam transverse coordinate at the DUT position. In order to achieve such resolution with 100×150 μm 2 pixel cells, the planes were tilted to 25 degrees to maximize charge sharing between pixels. Crucial for obtaining this performance is the alignment software, called Monicelli, specifically designed and optimized for this system. This paper will describe the telescope hardware, the data acquisition system and the alignment software constituting this particle tracking system for test beam users. [ABSTRACT FROM AUTHOR]

A new generation of Monolithic Active Pixel Sensors (MAPS), produced in a 65 nm CMOS imaging process, promises higher densities of on-chip circuits and, for a given pixel size, more sophisticated in-pixel logic compared to larger feature size processes. MAPS are a cost-effective alternative to hybrid pixel sensors since flip-chip bonding is not required. In addition, they allow for significant reductions of the material budget of detector systems, due to the smaller physical thicknesses of the active sensor and the absence of a separate readout chip. The TANGERINE project develops a sensor suitable for future Higgs factories as well as for a beam telescope to be used at beam-test facilities. The sensors will have small collection electrodes (order of µm) to maximize the signal-to-noise ratio, which makes it possible to minimize power dissipation in the circuitry. The first batch of test chips, featuring full front-end amplifiers with Krummenacher feedback, was produced and tested at the Mainzer Mikrotron (MAMI) at the end of 2021. MAMI provides an electron beam with currents up to 100 µA and an energy of 855 MeV. The analog output signal of the test chips was recorded with a high bandwidth oscilloscope and used to study the charge-sensitive amplifier of the chips in terms of waveform analysis. A beam telescope was used as a reference system to allow for track-based analysis of the recorded data. [ABSTRACT FROM AUTHOR]

The High Luminosity upgrade of the CERN Large Hadron Collider (HL-LHC) requires new radiation tolerant silicon pixel sensors. In the case of the CMS experiment, the first layer of pixel detectors will be installed at about 3 cm from the beam line, where an integrated fluence of about 20 × 1 0 15 n eq cm − 2 (1 MeV equivalent neutrons) is expected (HL-LHC Runs 4 and 5). The first tracker layer will be substituted before the start of HL-LHC Run 6. The 3D concept for silicon pixel sensors presents several advantages with respect to traditional (planar) sensors. Thanks to short anode-to-cathode distances, 3D sensors are much more resistant to radiation damage, making them suitable for use in the inner layer of the future tracker. This paper describes results from beam tests with highly irradiated planar and 3D sensor and RD53A readout chip combinations. RD53A is the first prototype in 65 nm technology developed by the RD53 collaboration for use in HL-LHC pixel detectors. The sensors were made in FBK foundry in Trento, Italy, and their development was done in collaboration with INFN (Istituto Nazionale di Fisica Nucleare, Italy). Both planar and 3D sensors feature a pixel area of 2500 μ m 2 and an active thickness of 150 μ m. The pixel detectors, irradiated to fluences up to 24 × 1 0 15 n eq cm − 2 , were tested in the DESY test beam facility and the analysis of the data shows excellent performances even for the highest irradiation fluences. All results are obtained in the framework of the CMS R&D activities. [ABSTRACT FROM AUTHOR]

A large-area and light-weight gas electron multiplier (GEM) detector was built at the University of Virginia as a prototype for the detector R&D program of the future Electron Ion Collider. The prototype has a trapezoidal geometry designed as a generic sector module in a disk layer configuration of a forward tracker in collider detectors. It is based on light-weight material and narrow support frames in order to minimize multiple scattering and dead-to-sensitive area ratio. The chamber has a novel type of two dimensional (2D) stereo-angle readout board with U–V strips that provides ( r , φ ) position information in the cylindrical coordinate system of a collider environment. The prototype was tested at the Fermilab Test Beam Facility in October 2013 and the analysis of the test beam data demonstrates an excellent response uniformity of the large area chamber with an efficiency higher than 95%. An angular resolution of 60 μ rad in the azimuthal direction and a position resolution better than 550 μm in the radial direction were achieved with the U–V strip readout board. The results are discussed in this paper. [ABSTRACT FROM AUTHOR]