Construction and beam-tests of silicon-tungsten prototype modules for the CMS High Granularity Calorimeter for HL-LHC

TL;DR

This paper reports on the development, construction, and beam testing of silicon-tungsten prototype modules for the CMS High Granularity Calorimeter, aiming to enhance detector performance for the HL-LHC upgrade.

Contribution

It presents the design, construction, and initial beam test results of silicon-tungsten prototype modules with advanced front-end electronics for the CMS HGCAL.

Findings

Achieved position resolution and timing measurements in beam tests.

Demonstrated the functionality of the Skiroc2-CMS front-end ASIC.

Validated the prototype modules with electron and pion beams.

Abstract

As part of its HL-LHC upgrade program, CMS is developing a High Granularity Calorimeter (HGCAL) to replace the existing endcap calorimeters. The HGCAL will be realised as a sampling calorimeter, including an electromagnetic compartment comprising 28 layers of silicon pad detectors with pad areas of 0.5 - 1.0 cm2 interspersed with absorbers. Prototype modules, based on 6-inch hexagonal silicon pad sensors with 128 channels, have been constructed and include many of the features required for this challenging detector. In 2016, beam tests of sampling configurations made from these modules have been conducted both at FNAL and at CERN using the Skiroc2 front- end chip (designed for the CALICE experiment for ILC). In 2017, the setup has been extended with CALICEs AHCAL prototype, a scinitillator based sampling calorimeter, and it was further tested in dedicated beam tests at CERN. There, the new Skiroc2-CMS front-end ASIC was used for the first time. We highlight final results from our studies in 2016, including position resolution as well as precision timing-measurements. Furthermore, the extended setup in 2017 is discussed and first results from beam tests with electrons and pions are shown.