Performance of the front-end electronics of the CMS electromagnetic calorimeter barrel for the High-Luminosity LHC

TL;DR

This paper evaluates the upgraded CMS electromagnetic calorimeter's front-end electronics performance during beam tests, demonstrating it meets the high-luminosity LHC requirements with excellent energy and time resolutions.

Contribution

It presents the first detailed performance analysis of the new front-end electronics for the CMS ECAL in beam tests, confirming it meets design specifications.

Findings

Energy resolution constant term < 0.6%

Time resolution < 30 ps for electrons > 50 GeV

Electronics performance meets HL-LHC requirements

Abstract

The performance of the CMS electromagnetic calorimeter upgraded readout electronics, developed for the High-Luminosity phase of the LHC, is discussed. Data collected in two beam test campaigns conducted in 2018 and 2021 at the H4 and H2 beam lines of the CERN SPS are analyzed. Time and energy resolutions are measured on a $5\times 5$ matrix of lead tungstate crystals equipped with prototypes of the new front end readout electronics, using electron and pion beams of energies spanning from 25 to 250 GeV. In both campaigns the constant term of the energy resolution is measured to be better than 0.6% and the time resolution for electrons with energies above 50 GeV is measured to be better than 30 ps, fulfilling the design requirements.