The CMS High Granularity Calorimeter upgrade for HL-LHC

The CMS collaboration is preparing to build replacement endcap calorimeters for the HL-LHC era. The new calorimeter endcap will be a highly-granular sampling calorimeter (HGCAL) featuring unprecedented transverse and longitudinal readout segmentation for both its electromagnetic and hadronic compartments. The granularity together with a foreseen timing precision on the order of a few tens of picoseconds will allow for measuring the fine structure of showers, will enhance pileup rejection and particle identification, whilst still achieving good energy resolution. The regions exposed to higher-radiation levels will use silicon as active detector material. The lower-radiation environment will be instrumented with scintillator tiles with on-tile SiPM readout. In addition to the hardware aspects, the reconstruction of signals, both online for triggering and offline, represents a challenging task - one where modern machine learning approaches are well applicable.

In this talk, the reasoning and ideas behind the HGCAL, the proof-of-concept of its design in test beam experiments, and the challenges ahead will be presented.

Event resources