Commissioning and Operation of the New CMS Phase-1 Pixel Detector

TL;DR

This paper details the commissioning, testing, and initial operation of the CMS Phase-1 pixel detector upgrade, highlighting its assembly, system validation, and performance with cosmic rays and proton-proton collisions.

Contribution

It presents the comprehensive commissioning process and initial operational results of the upgraded CMS pixel detector, demonstrating its readiness for high-luminosity conditions.

Findings

Successful assembly and system testing of the detector components

Effective in-situ commissioning using CMS DAQ system

Initial operation with cosmic rays and collisions confirmed detector performance

Abstract

The Phase-1 upgrade of the CMS pixel detector is built out of four barrel layers (BPix) and three forward disks in each endcap (FPix). It comprises a total of 124M pixel channels in 1,856 modules, and it is designed to withstand instantaneous luminosities of up to $2 \times 10^{34}\,$cm$^{-2}$s$^{-1}$. Different parts of the detector were assembled over the last year and later brought to CERN for installation inside the CMS tracker. At various stages during the assembly tests have been performed to ensure that the readout and power electronics and the cooling system meet the design specifications. After tests of the individual components, system tests were performed before the installation inside CMS. In addition to reviewing these tests, we also present results from the final commissioning of the detector in-situ using the central CMS DAQ system. Finally we review results from the initial operation of the detector first with cosmic rays and then with pp collisions.