J.L. Chevalley

Performance of a liquid argon Accordion calorimeter with fast readout

Abstract A prototype lead-liquid-argon electromagnetic calorimeter with parallel plates and Accordion geometry has been equipped with high speed readout electronics and tested with electron and muon beams at the CERN SPS. For a response peaking time of about 35 ns, fast enough for operation at the future hadron colliders, the energy resolution for electrons is 9.6%/√E[GeV] with a local constant term of 0.3% and a noise contribution of 0.33 E[ GeV ] . The spatial accuracy achieved with a detector granularity of 2.7 cm is 3.7 mm E[ GeV ] and the angular resolution 12 mrad at 60 GeV.

Performance of a liquid argon preshower detector integrated with an Accordion calorimeter

Abstract A prototype liquid argon preshower detector with a strip granularity of 2.5 mm has been tested at the CERN SPS in front of a liquid argon Accordion calorimeter. For charged tracks a signal-to-noise ratio of 9.4 and a space resolution of 340 μm were measured; the rejection power against overlapping photons produced in the decay of 50 GeV π 0 s is larger than 3; the precision on

Prototype tests of a “jet cell” drift chamber for large-area muon detection

Large-area, high-precision drift chambers, based on the “jet cell” concept, have been developed for the muon spectrometer of the ATLAS experiment at LHC. Emphasis is placed on the control and reduction of systematic error in the drift measurement and in the mechanical construction. Results of measurements on prototypes are given. These indicate that a global precision of σ ≲ 70 μm is achievable for large-area chambers.