Stairway to discovery: a report on the CMS programme of cross section measurements from millibarns to femtobarns

TL;DR

This paper reports on the CMS experiment's extensive measurements of proton-proton collision cross sections at the LHC, covering a wide range from common to rare processes, advancing our understanding of the Standard Model.

Contribution

It provides a comprehensive overview of cross section measurements across many processes, highlighting the experimental progress enabled by the LHC's high energies and luminosities.

Findings

Measured total inelastic cross section at unprecedented energies

Observed Higgs boson production and properties

Set limits on rare processes like Higgs pair production

Abstract

The Large Hadron Collider at CERN, delivering proton-proton collisions at much higher energies and far higher luminosities than previous machines, has enabled a comprehensive programme of measurements of the standard model (SM) processes by the CMS experiment. These unprecedented capabilities facilitate precise measurements of the properties of a wide array of processes, the most fundamental being cross sections. The discovery of the Higgs boson and the measurement of its mass became the keystone of the SM. Knowledge of the mass of the Higgs boson allows precision comparisons of the predictions of the SM with the corresponding measurements. These measurements span the range from one of the most copious SM processes, the total inelastic cross section for proton-proton interactions, to the rarest ones, such as Higgs boson pair production. They cover the production of Higgs bosons, top quarks, single and multibosons, and hadronic jets. Associated parameters, such as coupling constants, are also measured. These cross section measurements can be pictured as a descending stairway, on which the lowest steps represent the rarest processes allowed by the SM, some never seen before.