V. Zhukov

Studies of an MSGC equipped with a GEM grid as a tracking device

Abstract The performance of a Micro Strip Gas Counter (MSGC) equipped with a Gas Electron Multiplier (GEM) has been studied in a cosmic hodoscope. Using Ne/DME gas mixtures, measurements have been performed to study gain, transparency and spatial resolution.

Test of a CMS MSGC tracker prototype in a high-intensity hadron beam

Abstract A set of CMS MicroStrip Gas Chambers (MSGC) was exposed to a high-intensity 3 GeV /c pion beam at a CERN PS facility for a period of two weeks. The performance of the detectors is reported in terms of stability of efficiency and response to minimum ionising particles as well as to more heavily ionising fragments generated by nuclear interactions.

Operation of micro strip gas counters with Ne-DME gas mixtures

The performance of micro-strip gas counters (MSGCs) has been studied with gas mixtures of neon and dimethylether. The setup consisted of two 10 × 10 cm2 MSGC detectors placed in a cosmic ray hodoscope made of twelve drift chambers. Measurements are presented for the collected charge and the detection efficiency. A Monte Carlo simulation has been used to verify our understanding of the efficiency measurements. The simulation has also allowed to estimate the transverse diffusion coefficient of the electrons in the gas and to predict the spatial resolution of the detectors.

The MICROMEGEM detector

Abstract This article introduces the MICROMEGEM detector, a position-sensitive proportional gas counter produced using advanced Printed Circuit Board (PCB) technology. The detector is equipped with a Gas Electron Multiplier (GEM) foil placed 50 μm above a plane of pick-up strips. The GEM produces a first gas amplification which is extended below the GEM foil by applying a strong electric field between the strips and the lower electrode of the GEM. The array of strips is used for read-out to obtain 1-D positional information. We present results on the gas gain, the energy resolution and the rate capability. The behaviour in an intense beam of 300 MeV /c pions in presence of heavily ionizing particles has also been investigated.

OPERATION OF MICROSTRIP GAS COUNTERS WITH DME-BASED GAS MIXTURES

Abstract This paper reports on the operation of MicroStrip Gas Counters (MSGC) with several dimethylether (DME)-based gas mixtures. We present measurements of signal amplitude, detection efficiency and spatial resolution for minimum ionizing particles. We also show measurements of electron drift velocity and transverse diffusion coefficient in the counting gases considered. These results are discussed regarding the use of MSGC’s for tracking at high-energy physics experiments that have to deal with high particle rates.

Gas gain stability of MSGCs operating at high rate

Abstract Micro Strip Gas Counters (MSGCs) with coated and uncoated borosilicate glass substrates have been investigated on their high rate capability and long-term gas gain stability. It is shown that the gain remains almost constant at count rates up to 10 5 mm −2 s −1 when a semiconductive layer of S8900 glass or polydiamond is applied under or over the strips. The application of such a coating also favours the gain stability at long-term operation. However, the maximum attainable gas gain for coated substrates is 4–10 times smaller than for bare borosilicate glass supports. For the latter substrate type, we observe less ageing when the strips are made of nickel instead of aluminium or copper.

GAS GAIN STABILITY IN MSGCS AND MGCS AT HIGH-RATE OPERATION

MicroStrip Gas Counters (MSGCS) with strip patterns on bare and coated borosilicate glass as well as MicroGap Counters (MGCs) have been irradiated with 5.4 keV X-rays to investigate their high rate capability and ageing behaviour. n nThe application of semiconductive coatings under the strips of MSGCs results in an improved short- and long-term gain stability in comparison to counters with uncoated borosilicate substrates, for count rates up to 105 Hz/mm2. However, the absolute gain of a coated detector is significantly smaller than that of a conventional one. The MGC has high-rate characteristics, as good as those for coated MSGCs. Results on the ageing of MSGCs on coated and uncoated glass, and of the MGC, are presented.

Simulation study of silicon and gaseous tracking detectors

The performance of microstrip gaseous counters (MSGC, MSGC + GEM) and silicon microstrip sensors has been studied in view of their use in high luminosity tracking applications. Simulations of signal development in the detectors and subsequent signal treatment in the readout electronics were performed. The simulation results are compared with experimental data obtained in test beams.

Operation of a micro strip gas counter equipped with a gas electron multiplier

Abstract This paper reports on the operation of a Micro Strip Gas Counter (MSGC) equipped with a Gas Electron Multiplier (GEM) filled with Ar/CO2, Ne/CO2 and Ne/DME/CO2. We present measurements of the detection efficiency for minimum ionizing particles, and of the electron drift velocity and transverse diffusion coefficient in the counting gases considered.