Phase 1 upgrade of the CMS Hadron Barrel Calorimeter

The Phase 1 upgrade of the CMS Hadron Calorimeter (HCAL) involved the installation of new silicon photo -multiplier devices (SiPMs), which replaced older hybrid photodiodes (HPDs). SiPMs measure the scintillator light output with better signal/noise. The upgraded readout electronics also allow for increased longitudinal segmentation and better performance. This report describes the design, testing, installation, and commissioning of the HCAL Barrel Phase 1 upgrade. Performance results for the HCAL Endcap during Run 2 are presented and expectations for the HCAL Barrel during Run 3 are discussed.

Automated summary

This report describes the design, testing, installation, and commissioning of the HCAL Barrel Phase 1 upgrade for the CMS Hadron Calorimeter (HCAL). Performance results for the HCAL Endcap during Run 2 are presented and expectations for the HCAL Barrel during Run 3 are discussed.