The LHCb Muon Upgrade Cardini, A
Journal of instrumentation,
02/2014, Letnik:
9, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The LHCb collaboration is currently working on the upgrade of the experiment to allow, after 2019, an efficient data collection while running at an instantaneous luminosity of 2 x 10 super(33) cm ...super(-2)s super(-1). The upgrade will allow 40MHz detector readout, and events will be selected by means of a very flexible software-based trigger. The muon system will be upgraded in two phases. In the first phase, the off-detector readout electronics will be redesigned to allow complete event readout at 40 MHz. Also, part of the channel logical-ORs, used to reduce the total readout channel count, will be removed to reduce dead time in critical regions. In a second phase, higher-granularity detectors will replace the ones installed in highly irradiated regions, to guarantee efficient muon system performances in the upgrade data taking conditions.
Triple-GEM detectors with pad readout have been employed to equip the innermost region (R1) of the first station (M1) within the Muon system of the LHCb experiment. The GEM detectors have been ...operated with an Ar/CO2/CF4 = 45/15/40 gas mixture at a gas gain of about 4000 with an average particle flux of about 250 kHz/cm2. Throughout RUN1 and RUN2, spanning approximately 440 days of colliding beams, the GEM detectors accumulated a charge of up to 0.5 C/cm2. This paper presents a comparative analysis between a global irradiation test of GEM detectors at the Calliope facility (ENEA-Casaccia, 1.25 MeV γ ray flux from a 60Co source) and the GEMs operated at LHCb, focusing on the impacts of a CF4-based gas mixture. In both instances, the detectors were opened and the GEM foils were examined by the EN-MME-MM CERN group with a Field Emission Gun Scanning Electron Microscope (FEG-SEM) for a magnified image analysis and an X-Max Energy Dispersive X-ray Spectroscopy (EDS) for the chemical one.
This paper presents an approach to use strain data from a multi-girder, composite steel bridge for long-term Structural Health Monitoring (SHM). The bridge being studied is part of a research project ...at the University of Connecticut in which long-term SHM systems are being installed on a series of bridges throughout the State of Connecticut. Strain data is collected from normal truck traffic to determine live load stresses, load distribution factors, and the location of the neutral axis in each girder. Known weight trucks were used along with a finite element analysis for verification of the behavior. The long-term monitoring approach is based on determining the live load distribution factors, peak strains, and the neutral axis locations. The goal is to use existing, readily applied technology for SHM for long-term use on bridges that have raised concerns, due to corrosion noted in routine visual inspections, overloading, or fatigue sensitive details. The SHM system proposed can be used on a continuous basis to determine if there are significant changes in the structural behavior that would be indicative of major damage to either the girders or the concrete deck.
In the last years, high-resolution time tagging has emerged as a promising tool to tackle the problem of high-track density in the detectors of the next generation of experiments at particle ...colliders. Time resolutions below 50 ps and event average repetition rates of tens of MHz on sensor pixels having a pitch of 50 μm are typical minimum requirements. This poses an important scientific and technological challenge on the development of particle sensors and processing electronics. The TIMESPOT initiative (which stands for TIME and SPace real-time Operating Tracker) aims at the development of a full prototype detection system suitable for the particle trackers of the next-to-come particle physics experiments. This paper describes the results obtained on the first batch of TIMESPOT silicon sensors, based on a novel 3D MEMS (micro electro-mechanical systems) design. We demonstrate that following this approach, the performance of other ongoing silicon sensor developments can be matched and overcome. In addition, 3D technology has already been proved to be robust against radiation damage. A time resolution of the order of 20 ps has been measured at room temperature suggesting also possible improvements after further optimisations of the front-end electronics processing stage.
SUMMARY
Einstein Telescope (ET) is a proposed underground infrastructure in Europe to host future generations of gravitational-wave (GW) detectors. One of its design goals is to extend the ...observation band of terrestrial GW detectors from currently about 20 Hz down to 3 Hz. The coupling of a detector to its environment becomes stronger at lower frequencies, which makes it important to carefully analyse environmental disturbances at ET candidate sites. Seismic disturbances pose the greatest challenge since there are several important mechanisms for seismic vibrations to produce noise in ET, for example, through gravitational coupling, stray light, or through harmful constraints on the design of ET’s control system. In this paper, we present an analysis of the time-variant properties of the seismic field at the Sardinia candidate site of ET connected to anthropogenic as well as natural phenomena. We find that temporal variations of source distributions and of the noise spectra generally follow predictable trends in the form of diurnal, weekly, or seasonal cycles. Specific seismic sources were identified such as road bridges, which produce observable disturbances underground. This information can be used to adapt a detector’s seismic isolation and control system.
Abstract
This paper presents the detailed simulation of a
double-pixel structure for charged particle detection based on the
3D-trench silicon sensor developed for the TIMESPOT project and a
...comparison of the simulation results with measurements performed at
the π-M1 beam at PSI laboratory. The simulation is based on the
combined use of several software tools (TCAD, GEANT4, TCoDe and
TFBoost) which allow to fully design and simulate the device physics
response in very short computational time,
O(1–100 s) per simulated signal, by exploiting
parallel computation using single or multi-thread processors. This
allowed to produce large samples of simulated signals, perform
detailed studies of the sensor characteristics and make precise
comparisons with experimental results.
Hadron detection with a dual-readout fiber calorimeter Lee, S.; Cardini, A.; Cascella, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2017, Letnik:
866, Številka:
C
Journal Article
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In this paper, we describe measurements of the response functions of a fiber-based dual-readout calorimeter for pions, protons and multiparticle “jets” with energies in the range from 20 to 180 GeV. ...The calorimeter uses lead as absorber material and has a total mass of 1350 kg. It is complemented by leakage counters made of scintillating plastic, with a total mass of 500 kg. The effects of these leakage counters on the calorimeter performance are studied as well. In a separate section, we investigate and compare different methods to measure the energy resolution of a calorimeter. Using only the signals provided by the calorimeter, we demonstrate that our dual-readout calorimeter, calibrated with electrons, is able to reconstruct the energy of proton and pion beam particles to within a few percent at all energies. The fractional widths of the signal distributions for these particles (σ∕E) scale with the beam energy as 30%∕E, without any additional contributing terms.
Abstract
In this paper the results of a beam test characterization campaign of 3D trench silicon pixel sensors are presented. A time resolution in the order of 10 ps was measured both for ...non-irradiated and irradiated sensors up to a fluence of 2.5 × 10
16
1 MeV n
eq
cm
−2
. This feature and a detection efficiency close to 99% make this sensors one of the best candidates for 4D tracking detectors in High-Energy-Physics experiments.
Abstract We present first results obtained with a prototype 4D-tracking demonstrator, using sensors and electronics developed within the TimeSPOT project, and tested on a positive charged pion beam ...at CERN SPS. The setup consists of five small tracking layers in a row, having area of about 3 mm 2 each, three of which equipped with 3D-trench silicon sensors and two with 3D-column diamond sensors. The five layers are then read-out by a KC705 Xilinx board on a PC. We describe the demonstrator structure and operation and illustrate preliminary results on its tracking capabilities.