Large Scale Beam-Tests of the Silicon and Scintillator-SiPM Modules for the CMS High Granularity Calorimeter at the HL-LHC

Shilpi Jain

doi:10.1142/s201019451860073x

Abstract

The High Granularity Calorimeter (HGCAL) will replace the existing CMS endcap calorimeters during the High Luminosity run of the LHC (HL-LHC) era. The electromagnetic part, as well as the first layers of the hadronic part, foresees around 600 square metres of silicon sensors as the active material. The remainder of the HGCAL, in the lower radiation environment, will use plastic scintillators with on-tile silicon photomultiplier (SiPM) readout. Prototype hexagonal silicon modules, featuring a new ASIC (Skiroc2-CMS), together with a modified version of the scintillator-SiPM CALICE AHCAL, have been tested in beams at CERN. This setup represents a full slice through HGCAL. Results from MIP calibration, energy resolution, electromagnetic and hadronic shower-shapes are presented using electrons, pions and muons.

Highlights

The endcap CMS electromagnetic and hadronic calorimeter would face neutron fluences of 1016 neutrons/cm[2] for an integrated luminosity of 3000 f b−1 in the region of |η| ∼ 3
Upon seriously considering the issue, CMS has proposed the replacement of the current endcap calorimeters with a new high-granularity (HGCAL)[1] sampling calorimeter in the range 1.5 < |η| < 3.0 to address these challenges
The proposed design includes a silicon/lead electromagnetic section followed by two hadronic sections using stainless steel as the absorber material

Summary

Introduction

The endcap CMS electromagnetic and hadronic calorimeter would face neutron fluences of 1016 neutrons/cm[2] for an integrated luminosity of 3000 f b−1 in the region of |η| ∼ 3. Such a high radiation environment will cause irrecoverable radiation damage to the current endcap calorimeter. The average number of expected primary vertices will rise up to ∼ 200 in a single bunch crossing. Such a high pileup causes problems in the object reconstruction and identification.

Methods

Results

Conclusion