Prototype Test for Electromagnetic Calorimeter, FOCAL, at CERN-SPS Using Large Dynamic Range Readout Electronics

Abstract

A silicon–tungsten prototype calorimeter, for the proposed ALICE LS3-upgarde, was fabricated and tested at the CERN-SPS beamline facility in the year 2017. The calorimeter was designed with the help of GEANT4 simulation to perform in a high multiplicity density environment with optimised energy and position resolutions for incident energy up to 200 GeV. There were several tests conducted with different prototype configurations both at laboratory and CERN beamline facilities. The latest prototype in the series consists of 20 layers, each layer consisting of a 6 * 6 array of 1cm2 silicon pad detector, fabricated on a single 300 um thin wafer, and 1 radiation length (XR) thick, 10 cm * 10 cm pure tungsten plates as absorbers. Data was collected for pion, muon, and electron over a wide range of incident energies (20–180 GeV). Because of large energy deposition within the calorimeter by the electromagnetic showers, the readout electronics need to have a large dynamic range. Here, we will discuss the performances of the prototype, experimented at CERN-SPS, using a newly developed readout electronics (ANUINDRA) with a large dynamic range (up to 2.6 pC) and compare the improvements in this regard.