Liquid argon calorimetry with LHC-performance specifications

Abstract A novel geometry liquid argon calorimeter with accordion-shaped electrodes and converter plates has been recently conceived. Such a design allows for a fast readout and for a high granularity over large volumes with minimal dead spaces, properties which are considered essential for operation at the future hadron colliders. The first electromagnetic prototype based on this scheme has been built and tested at the CERN SPS. For a response peaking time of 140 ns an energy resolution of 10%/√ E (GeV) and a space resolution of 4.4 mm/√ E (GeV) with 2.7 cm cell size were achieved for electrons. A few preliminary results from a test with fast readout (response peaking time of less than 40 ns) are also presented.