The very forward CASTOR calorimeter of the CMS experiment

TL;DR

The paper reviews the design, calibration, and performance of the CASTOR calorimeter in the CMS experiment, which measures very forward particles at high radiation and magnetic fields in LHC collisions.

Contribution

It provides a comprehensive overview of the CASTOR calorimeter's design, calibration, and performance in measuring forward energy and jets in LHC proton and nuclear collisions.

Findings

Effective measurement of forward energy density and jets.

Successful operation under high radiation and magnetic fields.

Validation of detector performance with collision data.

Abstract

The physics motivation, detector design, triggers, calibration, alignment, simulation, and overall performance of the very forward CASTOR calorimeter of the CMS experiment are reviewed. The CASTOR Cherenkov sampling calorimeter is located very close to the LHC beam line, at a radial distance of about 1 cm from the beam pipe, and at 14.4 m from the CMS interaction point, covering the pseudorapidity range of $-$6.6 $\lt$ $\eta$ $\lt$ $-$5.2. It was designed to withstand high ambient radiation and strong magnetic fields. The performance of the detector in measurements of forward energy density, jets, and processes characterized by rapidity gaps, is reviewed using data collected in proton and nuclear collisions at the LHC.