Operation and performance of the CMS silicon strip tracker with proton-proton collisions at the CERN LHC

TL;DR

This paper discusses the commissioning, calibration, and operational performance of the CMS silicon strip tracker during proton-proton collisions at the CERN LHC, including temperature effects, system performance metrics, and radiation effects.

Contribution

It provides a comprehensive analysis of the CMS silicon strip tracker’s performance, including new insights into temperature dependence, radiation effects, and saturation issues during LHC operations.

Findings

Performance metrics like occupancy and signal-to-noise ratio are characterized.

Saturation effects in the APV25 readout chip were identified and addressed.

Radiation effects on sensors and optical links are consistent with simulations.

Abstract

Salient aspects of the commissioning, calibration, and performance of the CMS silicon strip tracker are discussed, drawing on experience during operation with proton-proton collisions delivered by the CERN LHC. The data were obtained with a variety of luminosities. The operating temperature of the strip tracker was changed several times during this period and results are shown as a function of temperature in several cases. Details of the system performance are presented, including occupancy, signal-to-noise ratio, Lorentz angle, and single-hit spatial resolution. Saturation effects in the APV25 readout chip preamplifier observed during early Run 2 are presented, showing the effect on various observables and the subsequent remedy. Studies of radiation effects on the strip tracker are presented both for the optical readout links and the silicon sensors. The observed effects are compared to simulation, where available, and they generally agree well with expectations.