Performance of a six gap MRPC built for large area coverage

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1994

Results from a beam test of the micro-gap chamber with minimum ionizing particles are reported. The dependence of the spatial resolution on the incidence angle of the beam with respect to the detector plane has been studied. Laboratory tests on new amplification structures, designed to increase gain and stability and to reduce the detector capacitance, are also shown. A maximum gas gain of 6000 and a specific capacitance of 0.5 pF/cm have been obtained. An optimised layout of the MGC's structure to avoid edge effects is discussed.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

A Semi-Digital Hadronic Calorimeter (SDHCAL) concept has been proposed for future leptonic collider experiments. The multigap resistive plate chamber (MRPC) is a candidate for the detector planes of this calorimeter. We have constructed three MRPCs of 1m × 1m size for tests of the SDHCAL. Two have 4 gas gaps and one has 5 gas gaps. To achieve high granularity for a calorimeter, the signals from the MRPC are readout by 1 × 1 2 pads. The three MRPCs have similar design but the fishing line spacer has different configurations. All three MRPCs were successfully tested in the T10 test beam facility at CERN with a gas mixture of 95% 2 2 4 and 5% 6 . The efficiency and multiplicity of these chambers have been studied. All chamber reached around 94% efficiency at the proper operating voltage.

Nuclear Physics A, 2010

The usage of electrodes made of semi-conductive glass is an inspiring way of improving the counting rate capability of resistive plate chamber. We developed 6 and 10-gap multigap resistive plate chambers (MRPCs) with low resistive silicate glass electrodes (bulk resistivity ∼ 10 10 Ωcm) for applications in time-of-flight (TOF) at high counting rates. These two prototypes were tested with secondary irradiation from 2.5 GeV proton beam at GSI. Time resolutions below 90 ps and efficiencies above 90% were obtained at counting rates up to 28 kHz/cm 2 for the 10-gap MRPC.

2010

In October and November 2008, the CMS collaboration conducted a programme of cosmic ray data taking, which has recorded about 270 million events. The Resistive Plate Chamber system, which is part of the CMS muon detection system, was successfully operated in the full barrel. More than 98 % of the channels were operational during the exercise with typical detection efficiency of 90 %. In this paper, the performance of the detector during these dedicated runs is reported. 2 2 RPC system layout RB2 out for the second one). The third and fourth DT layers are complemented with a single RPC layer, placed on their inner side (RB3 and RB4). A detailed description of the muon system geometry can be found in Ref.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1996

In this paper we study the performance of a wide gap RPC and compare it with that of a narrow gap RPC, both operated in avalanche mode. We have studied the total charge produced in the avalanche. We have measured the dependence of the performance with rate. In addition we have considered the effect of the tolerance of gas gap and calculated the power dissipated in these two types of RPC. We find that the narrow gap RPC has better timing ability; however the wide gap has superior rate capability, lower power dissipation in the gas volume and can be constructed with less stringent mechanical tolerances.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016

The instantaneous luminosity of the Large Hadron Collider at CERN will be increased up to a factor of five with respect to the present design value by undergoing an extensive upgrade program over the coming decade. The most important upgrade project for the ATLAS Muon System is the replacement of the present first station in the forward regions with the so-called New Small Wheels (NSWs). The NSWs will be installed during the LHC long shutdown in 2018/19. Small-Strip Thin Gap Chamber (sTGC) detectors are designed to provide fast trigger and high precision muon tracking under the high luminosity LHC conditions. To validate the design, a full-size prototype sTGC detector of approximately 1.2 × 1.0 m 2 consisting of four gaps has been constructed. Each gap provides pad, strip and wire readouts. The sTGC intrinsic spatial resolution has been measured in a 32 GeV pion beam test at Fermilab. At perpendicular incidence angle, single gap position resolutions of about 50 µm have been obtained, uniform along the sTGC strip and perpendicular wire directions, well within design requirements. Pad readout measurements have been performed in a 130 GeV muon beam test at CERN. The transition region between readout pads has been found to be 4 mm, and the pads have been found to be fully efficient.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1993

The micro-gap chamber (MGC), a new type of position sensitive proportional gas counter, is introduced . The device is built using microelectronics technology . In this detector the separation between the electrodes collecting the avalanche charge (the anode-cathode gap) is only a few microns. The time it takes to collect the positive ions is therefore very short ( =10 ns). The speed of the device now equals that of solid state detectors but it is more than three orders of magnitude higher than in standard proportional counters and one order of magnitude higher than in the recently introduced microstrip gas chamber (MSGC). As a result, the rate capability is extremely high ( > 9 x 10 6 c/mm2 s) . The amplifying electric field around the thin anode microstrip extends over a small volume but is very intense (270 kV/mm) . It provides a gas gain of 2.5 x 10 3 at 400 V with 14% (FWHM) energy resolution at 5.4 keV. The anode pitch is 100 win and the readout is intrinsically two-dimensional . Because there is practically no insulating material in view, charging was not observed even at the highest rate . This device seems very well suited for instrumentation of the tracking system at the new hadron colliders (LHC/SSC) as well as in many other fields of research .

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2007

We have built Multigap Resistive Plate Chambers (MRPC) with six 300 mm gas gaps and an active area of 158 Â 82 cm 2 . The signals are generated on 2.5 cm wide copper pickup strips; these are read out at each end thus allowing the position of the hit along the strip to be obtained from the time difference. Using three of these chambers we have set up a cosmic tracking system in a similar manner as planned for the Extreme Energy Events (EEE) project. The details of the set-up are presented in this paper. In addition we discuss the time and position resolution of these MRPCs measured using cosmic rays. r

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2018

A 20 gas gaps multigap resistive plate chamber (MRPC) was built with thin (0.28 mm) glass sheets and 0.16 mm gas gap size. This chamber reaches 97% efficiency at 18.4 kV and a time resolution of 32 ps (sigma) at an instantaneous particle flux around 2.5 kHz/cm 2. Compared to a 6 gaps MRPC with 0.22 mm gas gap, this 20-gap MRPC shows a higher rate capability and much better time resolution. The efficiencies of the 20-gap MRPC reach 95%, 93% and 88% at instantaneous fluxes of 10 kHz/cm 2 , 14.5 kHz/cm 2 and 20 kHz/cm 2 , respectively. The efficiencies of the 6-gap MRPC at the same flux are 90%, 85% and 77%. The time resolution of 20-gap MRPC degrades with the increase of particle flux. However, a time resolution of 39 ps was obtained at an instantaneous flux of 10 kHz/cm 2 .

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2000

RPCs are strong candidates for the outer regions of the LHCb muon detector. We have tested single-gap and dual-gap detectors built with low-resistivity phenolic plates (ρ = 9 • 10 9 Ωcm) and operated in avalanche mode. Measurements have been performed over a wide range of beam intensities and on the GIF at CERN. The results are presented and discussed, with special emphasis on the detection efficiency.