Dimuons in pp and PbPb collisions with the CMS experiment

TL;DR

This paper reports on CMS measurements of dimuon production in proton-proton and lead-lead collisions at the LHC, providing insights into QCD matter and validating theoretical models through various boson and quarkonium yields.

Contribution

It presents the first high-precision measurements of dimuon production in PbPb collisions at the LHC, confirming theoretical predictions and the Glauber model's applicability in heavy-ion environments.

Findings

No modification of Z boson yields in PbPb compared to pQCD predictions

Confirmation of Glauber scaling for perturbative cross sections

Status update on quarkonia measurements in different collision systems

Abstract

The unprecedented centre-of-mass energy available at the LHC offers unique opportunities for studying the properties of the strongly-interacting QCD matter created in PbPb collisions at extreme temperatures and very low parton momentum fractions. With its high precision, large acceptance for tracking and calorimetry, and a trigger scheme that allows analysis of each minimum bias PbPb event, CMS is fully equipped to measure dimuons in the high multiplicity environment of nucleus-nucleus collisions. Such probes are especially relevant for these studies since they are produced at early times and propagate through the medium, mapping its evolution. Inclusive and differential measurements of the Z boson yield will be shown, establishing that no modification is observed with respect to theoretical next-to-leading order pQCD calculations. The validity of the Glauber scaling for perturbative cross sections in nucleus-nucleus collisions at the LHC is confirmed. In addition, the status of the quarkonia measurements (primary and secondary J/\psi, and the 3 Upsilon states) will be reviewed, both in pp and in PbPb collisions.