C.-E. Wulz

Bunch crossing identification at LHC using a mean timer technique

Abstract A novel method was developed to obtain precise timing of muon hits in drift tubes at the first trigger level, and hence to associate a detected muon with the bunch crossing in which it originated. A very good time resolution of ∼ 2 ns was obtained. Some other topics related to muon detection were investigated.

TEST OF A RESISTIVE PLATE CHAMBER OPERATING WITH LOW GAS AMPLIFICATION AT HIGH-INTENSITY BEAMS

Abstract We present results on efficiency and time resolution of a resistive plate chamber operating at low gas amplification. The measurements were done within the programme of the RD5 experiment at CERN with a pion beam of flux 0.1–3.9 kHz/cm2.

Higher order Bose-Einstein correlations in pp̄ collisions at √s=630 and 900 GeV

Abstract Higher order Bose-Einstein correlations up to fifth order, of particles produced in proton-antiproton collisions, are presented using UA1 data at √ s =630 and 900 GeV. The results are compared with theoretical calculations to investigate the primary assumptions for the parametrization of the correlation functions.

Study of resistive plate chambers for muon detection at hadron colliders

Abstract We present the performance of a hodoscope made of resistive plate chambers (RPC) installed in the RD5 experiment at CERN and exposed to beams of high energy muons and pions. The efficiency as a function of the particle flux is studied for different resistivities. A substantial improvement is obtained with plates of lower resistivity. Tracking muons through the RPC and using the bending power of a 2.7 Tm iron toroid, a simple trigger algorithm is used to select large momentum muons.

Pattern Comparator Trigger (PACT) for the muon system of the CMS experiment

The general scheme for the fast, pipelined first level trigger on high pt muons in the CMS detector at LHC is presented. The prototype PACT system was tested in the high momentum muon beams in the RD5 experiment during 1993/94 runs. The obtained efficiency curves are shown.

A uranium scintillator calorimeter with plastic-fibre readout

Abstract We have developed a method for reading out scintillator plates in a compact calorimeter using embedded wavelength-shifting fibres coupled to photomultipliers. A test calorimeter using this technique, with uranium plates as the passive medium, was placed in test beams of 1 to 80 GeV. Results on resolution, uniformity, and electron-pion discrimination are presented, as well as a discussion of compensation (the near-equality of electron and hadron responses).

Measurement of the efficiency and time resolution of double-gap resistive plate chambers

Abstract We describe a detector built by assembling together two resistive plate chambers and read out by a single median electrode plane segmented in strips. We present results of measurements of the efficiency and of the time response as a function of the particle flux.

Position and timing resolution of interpolating cathode strip chambers in a test beam

Abstract Design and construction details are presented of a four-layer, position sensitive, cathode strip chamber and a low cost, highly multiplexed readout system based on monolithic circuit technology that are well suited for a muon detector at future hadron colliders. Track location is determined by interpolation of the cathode induced charge, using a new design with intermediate strips between readout nodes to reduce the number of channels and improve position resolution and linearity. Results are reported from tests with an 55 Fe source and a 300 GeV/ c muon beam in RD5 at CERN. The beam test demonstrated position resolution of 40 μ m per layer which is less than 1% of the readout pitch. The timing resolution for the entire four-layer detector was 3.6 ns r.m.s. which is adequate for fully efficient beam crossing identification in an LHC experiment.

Parallel plate chambers: a fast detector for ionizing particles

Abstract The parallel plate chamber technique is summarized together with recent results of tests concerning efficiency, time resolution, high rate capability and radiation resistance.

The construction and performance of single-layer honeycomb strip chambers in the TRACAL detector of RD5

Abstract Single layer honeycomb strip chambers have been constructed for the tracking calorimeter TRACAL. This detector is a component of the RD5 experimental test setup at CERN, where aspects of muon detection in LHC conditions are studied. The construction of the chambers is described and the excellent spatial resolution obtained from strip signals (σ