Measurement of the inelastic $pp$ cross-section at a centre-of-mass energy of 13\,TeV

TL;DR

This paper reports a precise measurement of the inelastic proton-proton cross-section at 13 TeV using the LHCb detector, providing key data for understanding proton interactions at high energies.

Contribution

The study presents the first measurement of the inelastic pp cross-section at 13 TeV in the specified pseudorapidity range, with an extrapolation to full phase space.

Findings

Fiducial cross-section: 62.2 mb with uncertainties

Total inelastic cross-section: 75.4 mb with uncertainties

Updated inelastic cross-section at 7 TeV reported

Abstract

The cross-section for inelastic proton-proton collisions at a centre-of-mass energy of 13\,TeV is measured with the LHCb detector. The fiducial cross-section for inelastic interactions producing at least one prompt long-lived charged particle with momentum $p>2$\,GeV/$c$ in the pseudorapidity range $2<\eta<5$ is determined to be $\sigma_{\rm acc}= 62.2 \pm 0.2 \pm 2.5$\,mb. The first uncertainty is the intrinsic systematic uncertainty of the measurement, the second is due to the uncertainty on the integrated luminosity. The statistical uncertainty is negligible. Extrapolation to full phase space yields the total inelastic proton-proton cross-section $\sigma_{\rm inel}= 75.4 \pm 3.0 \pm 4.5$\,mb, where the first uncertainty is experimental and the second due to the extrapolation. An updated value of the inelastic cross-section at a centre-of-mass energy of 7\,TeV is also reported.