Abstract
The front-end electronics of the ATLAS muon drift-tube chambers will be upgraded in the experiment’s phase-II upgrade to comply with the new trigger and read-out scheme at the HL-LHC. A new ...amplifier shaper discriminator chip was developed in 130 nm Global Foundries technology for this upgrade. A preproduction of 7500 chips was launched in 2019 and tested in 2020. The functionality of the chips, the test set-up and test procedure and results showing a yield of 93% are presented. The certification of the preproduction was followed by the production of 80,000 chips in fall 2020. The tests of a sample of 2949 preproduction and 1174 production chips gave a production yield > 93%.
In order to fully exploit the physics potential of the ATLAS experiment at the HL-LHC, the trigger rate of and maximum latency of the first-level trigger system will be increased to 1 MHz and 10μs, ...respectively. In addition, a new first-level muon track trigger with high momentum resolution based on the ATLAS precision Muon Drift-Tube (MDT) chambers will be employed which requires triggerless readout. The TDC ASICs of the current front-end electronics of the MDT chambers are incompatible with these requirements. The front-end boards, each with a TDC chip and three 8-channel amplifier–shaper–discriminator (ASD) chips have to be replaced. Therefore, a new octal ASD2 ASIC has been developed in modern 130 nm IBM/Global Foundries CMOS technology. The chip also contains a Wilkinson ADC to perform both time-over-threshold and signal charge measurement. The ASD design has been fully qualified for the serial production of 80000 chips for ATLAS. The performance in terms of signal rise time and channel uniformity significantly surpasses the one of the previous chip while keeping the power consumption constant. In addition to the characterization with test pulses, several chips have been mounted on the front-end boards and tested in a muon beam at the Gamma Irradiation Facility GIF++ at CERN up to high counting rates where the superior drift time and spatial resolution becomes evident.
•New Amplifier–Shaper–Discriminator chips for the readout of ATLAS (s)MDT chambers at HLLHC.•Design of new ASD chip in 130 nm CMOS IBM/Global Foundries technology completed.•Improved signal rise time and channel uniformity.•Radiation hardness far better than needed in the ATLAS muon spectrometer at HLLHC.•Successful full performance test in a muon beam at CERN under intense gamma irradiation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Extraordinary emittance requirements in the nm range (normalized) and pulse lengths down to a level of ∼10 fs for REGAE bunches demand both operation at low bunch charges on the sub-pC scale and a ...very careful beam handling. The S-band RF deflecting cavity is intended for diagnostics of the longitudinal bunch parameters. For the first time a deflecting structure, specially developed and optimized for bunch rotation has been realized for the REGAE RF deflector. The developed cavity provides a minimized level of aberrations in the distribution of the deflecting field combined with an improved RF efficiency. The main steps in the cavity design, construction and tuning are described.
Background: The cultures used in the production of "bio-yoghurts" typically consist of a blend of traditional yogurt starters, such as S. thermophilus and L. delbrueckii subsp. bulgaricus, along with ...probiotics like L. acidophilus, L. casei, L. reuteri, and Bifidobacterium spp. These probiotics, although beneficial, face challenges thriving in milk due to its short fermentation time (4–5 hours). The rapid acidification caused by the starter’s results in probiotic levels dropping below the "therapeutic minimum" during the intended refrigerated shelf life of the product. A potential solution to this issue lies in leveraging lactic acid bacteria isolated from the human milk which possess both robust probiotic characteristics and starter properties. Incorporating such strains in yogurt starter could address the acidity imbalance and contribute to maintaining optimal probiotic levels throughout the refrigerated shelf life of the product. Objective: This research aims to develop a new generation of sustainable functional yoghurts suitable for consumers of all ages using as starters predominant probiotic lactic acid bacteria isolated from the breast milk of healthy women. Results: This study marks the first implementation of the critical dilution culture method in sterile cow milk for the selection of predominant lactic acid bacteria (LABs) from women's breast milk. Remarkably, all samples yielded LAB capable of independently fermenting milk. Although breast milk is a good medium for the growth of residential lactic acid bacteria, it never coagulates due to low concentration of caseins. The isolated strains, identified as belonging to the species L. delbrueckii subsp. lactis, L. fermentum, L. casei subsp. sakei, Streptococcus thermophiles and Lactococcus lactis, exhibited probiotic and adaptive properties essential for gut colonization in humans. Utilizing symbiotic LAB starters were created functional yogurts with heightened technological, physicochemical, and sensory characteristics. Conclusions: Yogurts fermented using human milk LABs are safe and can be recommended as a functional dairy food, for pregnant women as well as for pre-term and full-term infants as a substitute/supplement for mother's milk. Moreover, these LABs can be included in infant formulas or used in pre-treatment of infant formula milk to improve its nutritional value and safety. Keywords: Breast milk, lactic acid bacteria, probiotic, milk fermentation, functional yogurt
Single muon triggers are crucial for the physics programmes at hadron collider experiments. To be sensitive to electroweak processes, single muon triggers with transverse momentum thresholds down to ...20 GeV and dimuon triggers with even lower thresholds are required. In order to keep the rates of these triggers at an acceptable level these triggers have to be highly selective, i.e. they must have small accidental trigger rates and sharp trigger turn-on curves. The muon systems of the LHC experiments and experiments at future colliders like FCC-hh will use two muon chamber systems for the muon trigger, fast trigger chambers like RPCs with coarse spatial resolution and much slower precision chambers like drift-tube chambers with high spatial resolution. The data of the trigger chambers are used to identify the bunch crossing in which the muon was created and for a rough momentum measurement while the precise measurements of the muon trajectory by the precision chambers are ideal for an accurate muon momentum measurement. A compact muon track finding algorithm is presented, where muon track candidates are reconstructed using a binning algorithm based on a 1D Hough Transform. The algorithm has been designed and implemented on a System-On-Chip device. A hardware demonstration using Xilinx Evaluation boards ZC706 has been set-up to prove the concept. The system has demonstrated the feasibility to reconstruct muon tracks with a good angular resolution, whilst satisfying latency constraints. The demonstrated track-reconstruction system, the chosen architecture, the achievements to date and future options for such a system will be discussed.
Abstract
The Muon System of the ATLAS experiment at the CERN LHC will be upgraded for the high-luminosity phase of LHC to cope with higher rates and higher radiation levels. Most of the Muon-System ...on-detector electronics will be replaced. Commercial low-dropout voltage regulators have been considered as a robust, low-noise and economic solution to power distribution. These components should be selected based on their capability to comply to radiation requirements. We tested 7 different types of CMOS LDOs, monitoring online the output voltage of 10 samples of each type. Irradiations were performed in the Radial Channel 1 of the RSV TAPIRO fast neutron reactor at ENEA Casaccia (Rome), to test resistance to non-ionizing energy loss, and at the PIF 200 MeV proton beam at PSI (Villigen), to test for total ionizing dose and single event effects. The experimental setup and the results are presented and discussed in this paper.
The distribution and control of temperature analyses during the brazing of lengthy accelerating structures, by induction heating usage, have been carried out. The problem of individual elements ...positioning, relative to each other during brazing, is solved. The results of metallographic studies for brazing zones are shown.
A full integral of a polynomial is defined as its integral with the property that any multiple root of the polynomial is a root of this integral. The paper investigates relationships between the ...existence of a full integral and the form of a polynomial. In particular, it is proved that a full integral exists if the polynomial has no more than one multiple root. On the other hand, if the number of multiple roots of a polynomial strictly exceeds the number of its simple roots increased by one, then the polynomial has no full integral. Bibliography: 7 titles.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Phase-II Upgrade of the ATLAS Muon Detector requires new electronics for the readout of the MDT drift tubes. The first processing stage, the Amplifier-Shaper-Discriminator (ASD), determines the ...performance of the readout for crucial parameters like time resolution, gain uniformity, efficiency and noise rejection. An 8-channel ASD chip, using the IBM 130 nm CMOS 8RF-DM technology, has been designed, produced and tested. The area of the chip is 2.2 x 2.9 mm super(2) size. We present results of detailed measurements as well as a comparison with simulation results of the chip behavior at three different levels of detail.
For a reliable and timely forecast of Space Weather world-wide networks of particle detectors are located at different latitudes, longitudes and altitudes. To provide better integration of these ...networks the data acquisition system is facing a challenge to establish reliable data exchange between multiple network nodes which are often located in hardly accessible locations and operated by small research groups. In this article we want to present a data acquisition system for new establishing SEVAN (Space Environmental Viewing and Analysis Network) elaborated on top of free open-source technologies. Our solution is organized as a distributed network of uniform components connected by standard interfaces. The main component is URCS (Unified Readout and Control Server) which controls frontend electronics, collects data and makes preliminary analysis. The URCS operates fully autonomous. Essential characteristics of software components and electronics are remotely controllable via a dynamic web interface, the data is stored locally for certain amount of time and distributed on request to other nodes over web services. To simplify data exchange with collaborating groups we are using an extensible XML based format for data dissemination. The data acquisition system at Aragats Space Environmental Center in Armenia was started November, 2006. Seven particle monitors are located at 2000 and 3200 meters above sea level at a distance of 40 and 60 km from data analysis servers in Yerevan, Armenia. The reliability of the service was proofed by continuous monitoring of incident cosmic ray flux.
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