First measurement of the top quark pair production cross section at $\sqrt{s} = 13.6 \, \mathrm{TeV}$ at the CMS experiment

TL;DR

This paper reports the first measurement of top quark pair production cross section at 13.6 TeV at the CMS experiment, validating the new data from LHC Run 3 with a novel combined decay channel method.

Contribution

It introduces a new combined method for measuring the top quark pair production cross section at 13.6 TeV, reducing experimental uncertainties in the process.

Findings

Measured cross section: 887 pb with uncertainties

Results agree with Standard Model predictions

First validation of CMS data at 13.6 TeV

Abstract

We present the first measurement of the top quark pair production cross section at the new LHC center-of-mass energy of $\sqrt{s} = 13.6 \, \mathrm{TeV}$, using $1.20 \, \mathrm{fb}^{-1}$ of data recorded at the CMS detector. We use a new method combining dilepton and lepton+jets decay channels, constraining several experimental uncertainties in situ. A cross section of $887^{+43}_{-41}(\mathrm{stat+syst}) \pm 53 (\mathrm{lumi}) \, \mathrm{pb}$ is measured, in agreement with the standard model. This result constitutes a first validation of the new data taken by CMS in LHC Run 3.