Design and electronics commissioning of the physics prototype of a Si-W electromagnetic calorimeter for the International Linear Collider

Abstract

The CALICE collaboration is studying the design of high performance electromagnetic and hadronic calorimeters for future International Linear Collider detectors. For the electromagnetic calorimeter, the current baseline choice is a high granularity sampling calorimeter with tungsten as absorber and silicon detectors as sensitive material. A "physics prototype" has been constructed, consisting of thirty sensitive layers. Each layer has an active area of 18 × 18 cm 2 and a pad size of 1 × 1 cm 2 . The absorber thickness totals 24 radiation lengths. It has been exposed in 2006 and 2007 to electron and hadron beams at the DESY and CERN beam test facilities, using a wide range of beam energies and incidence angles. In this paper, the prototype and the data acquisition chain are described and a summary of the data taken in the 2006 beam tests is presented. The methods used to subtract the pedestals and calibrate the detector are detailed. The signal-overnoise ratio has been measured at 7.63 ± 0.01. Some electronics features have been observed; these lead to coherent noise and crosstalk between pads, and also crosstalk between sensitive and passive areas. The performance achieved in terms of uniformity and stability is presented.

Hadronic energy resolution of a highly granular scintillator-steel hadron calorimeter using software compensation techniques

“…The complete CALICE setup in the H6 beam line at the CERN SPS for the 2007 beam period, illustrated in figure 1, consisted of a silicon-tungsten electromagnetic sampling calorimeter (ECAL) [9], the AHCAL, and a scintillator-steel tail catcher and muon tracker (TCMT) [10]. The test beam setup was also equipped with various trigger and beam monitoring devices.…”

“…The ECAL [9] has a total depth of 24 radiation lengths (approximately 1 nuclear interaction length λ I ) and consists of 30 active silicon layers arranged in three longitudinal sections with different absorber thicknesses. In this study, the ECAL was used for event selection and early shower detection.…”

Beam test performance of the SKIROC2 ASIC

“…A silicon-tungsten ECAL physics prototype to demonstrate the principle of highly granular electromagnetic calorimeters has been operated successfully in beam test campaigns at DESY, CERN and FNAL [3,4]. The next, so-called "technological", prototype addresses the engineering challenges associated with the realisation of highly granular calorimeters.…”

Track segments in hadronic showers in a highly granular scintillator-steel hadron calorimeter

“…During data taking at the CERN SPS, a silicon-tungsten electromagnetic calorimeter (SiW-ECAL) [7] was installed upstream of the AHCAL together with a downstream tail catcher and muon tracker (TCMT) [8]. These detectors are not explicitly used in the analysis presented here, but the ECAL contributes to the event selection discussed below.…”