Spatial resolution of RPC in streamer mode Arnaldi, R.; Baldit, A.; Barret, V. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
09/2002, Letnik:
490, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
In the framework of an R&D program on the ALICE dimuon trigger system, the spatial resolution of Resistive Plate Chambers working in streamer mode has been investigated during beam tests. Preliminary ...studies with cosmic rays had evidenced a dependence of the charge profile to the high voltage and to the gas mixture. However, the spatial resolution measured from the beam tests is only slightly varying with the high voltage and is close to the expected value
w/
12
where w is the strip pitch, for strips of 1 and
2
cm
width. The probability to fire a strip as a function of the distance from the strip to the particle impact has been measured for various high voltages. A simple parametrisation of this probability has been achieved. This allows to predict, under various working condition, the cluster size distributions for RPCs with different strip widths and also to account for the effect of the particle incident angle.
The details of the construction of the neutron Zero Degree Calorimeters (ZN) of the ALICE Experiment, as well as their performances, will be presented. These spaghetti calorimeters will measure the ...energy lost by spectator nucleons in heavy-ion collisions. They are made of an absorber (tungsten alloy) filled with silica fibers, in which the charged particles of the shower produce Cherenkov light. The final neutron calorimeters have been built and their performances studied at the CERN SPS using pion and positron beams with momentum ranging from 50 to 150
GeV/
c
. The main features like linearity of the response and resolution as a function of energy will be presented.
ALICE, the experiment dedicated to the study of heavy ion collisions at LHC, will be equipped with a forward spectrometer to identify heavy quarkonium states from their decay into muons. The trigger ...system of the spectrometer consists of four planes of resistive plate chambers, front-end and fast-decision electronics. It is designed to reconstruct muon tracks in a large background environment and to provide a fast trigger signal to the spectrometer. We present results from the test of a trigger prototype that have been carried out with the muon beam of the CERN/SPS at the Gamma Irradiation Facility (GIF). The track finding efficiency as well as the robustness of the system to the uncorrelated background induced on the detector by the GIF source are discussed. Special emphasis is put on timing aspects which are crucial at LHC. A self-consistent method for timing optimization and monitoring is proposed. The findings, although specific to ALICE, are relevant to any muon trigger system operating at LHC.
► For the IFMIF/EVEDA RFQ linac, engineering design of the RF input coupler is carried out. ► The RF input coupler with a cooling port (L=λ/4), based on a 6 1/8in. co-axial waveguide, is designed for ...the CW operation. ► Three cooling channels are installed into the inside of loop antenna, the outer-conductor and the inner-conductor around RF window. ► For the RF transmitted tests, a coupling cavity with a ridge type structure is also designed.
For the IFMIF/EVEDA RFQ linac, engineering design of the RF input coupler is carried out. The RF input coupler with a cooling port (L=λ/4), based on a 6 1/8in. co-axial waveguide, is designed for the CW operation. Three cooling channels are installed into the inside of loop antenna, the outer-conductor and the inner-conductor around RF window. For the loop size, RF coupling factors on beam loading are evaluated with based on the measured S11 parameter and Q value on aluminum RFQ module. In order to fulfill the acceptance Q0 value of 9000 for the RFQ, the insertion depth of L=45mm is chosen. For this loop antenna size, magnetic field strength around the loop and surface loss density on the loop are evaluated, it is found to satisfy with the RF coupler acceptance values. Coupling cavity with ridge-type structure is also designed for the RF transmitted power test. It is evaluated to be 7.2kW and 0.5W/cm2 for RF power dissipation and RF surface loss density on the RF transmitted power of 200kW.
Influence of temperature and humidity on bakelite resistivity Arnaldi, R; Baldit, A; Barret, V ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2000, Letnik:
456, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The use of phenolic or melaminic bakelite as RPC electrodes is widespread. The electrode resistivity is an important parameter for the RPC performance. As recent studies pointed out, the bakelite ...resistivity changes with temperature and is influenced by humidity. In order to gain a quantitative understanding on the influence of temperature and humidity on RPC electrodes, we assembled an apparatus to measure resistivity in well-controlled conditions. A detailed description of the experimental set-up as well as the first resistivity measurements for various laminates in different environmental conditions are presented.
The SLIM5 low mass silicon tracker demonstrator Bettarini, S.; Ratti, L.; Rizzo, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2010, Letnik:
623, Številka:
3
Journal Article
Recenzirano
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.
Study of the resistive plate chambers for the ALICE Dimuon Arm Arnaldi, R; Baldit, A; Barret, V ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2000, Letnik:
456, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The trigger system for the ALICE Dimuon Arm will be based on Resistive Plate Chambers (RPC). A RPC prototype, with electrodes made of low-resistivity bakelite (
ρ∼3×10
9
Ω
cm
) has been tested both ...at the SPS and at the Gamma Irradiation Facility. The results for the operation in the streamer mode are presented here.
Commissioning of the ALICE muon spectrometer trigger at LHC Ahn, S.; Arnaldi, R.; Baek, Y. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2012, Letnik:
661
Journal Article
Recenzirano
ALICE (a large ion collider experiment) is the LHC experiment dedicated to the study of ultra-relativistic heavy ion collisions. The ALICE muon spectrometer covers a large range in pseudo-rapidity ...and is designed to study quarkonia and heavy flavours decaying into (di-)muons. The high particle multiplicities environment in such collisions require a specific, fast and efficient trigger system, the muon trigger. It consists of four planes of RPC detectors, covering an area of 36
m
2 each, 21k front-end channels and a fast-decision electronics. The muon trigger is designed to reconstruct (muon) tracks and deliver a trigger signal each 25
ns (40
MHz) with a total latency of 800
ns. The hit position on the RPC is measured in two orthogonal directions with an accuracy of about 1
cm. The performance measured with the first p–p collisions at
(
s
)
=
900
GeV
carried out in December 2009 is reported.
A 4096-pixel MAPS device with on-chip data sparsification Gabrielli, A.; Batignani, G.; Bettarini, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2009, Letnik:
604, Številka:
1
Journal Article
Recenzirano
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/cm
2 if a master clock of 80
MHz is used, while maintaining an overall efficiency over 99%.
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