Charged-particle distributions in $pp$ interactions at $\sqrt{s}=8$ TeV measured with the ATLAS detector

TL;DR

This paper reports detailed measurements of charged-particle distributions in proton-proton collisions at 8 TeV using the ATLAS detector, providing data for testing and refining particle physics models.

Contribution

It presents the first comprehensive set of charged-particle distribution measurements at 8 TeV with high-statistics data and compares them to various Monte Carlo models.

Findings

Distributions of charged particles are measured across different kinematic regions.

Results show discrepancies between data and some Monte Carlo predictions.

High-multiplicity final states are characterized and analyzed.

Abstract

This paper presents measurements of distributions of charged particles which are produced in proton--proton collisions at a centre-of-mass energy of $\sqrt{s} = 8$ TeV and recorded by the ATLAS detector at the LHC. A special dataset recorded in 2012 with a small number of interactions per beam crossing (below 0.004) and corresponding to an integrated luminosity of $160 \mathrm{\mu b^{-1}}$ was used. A minimum-bias trigger was utilised to select a data sample of more than 9 million collision events. The multiplicity, pseudorapidity, and transverse momentum distributions of charged particles are shown in different regions of kinematics and charged-particle multiplicity, including measurements of final states at high multiplicity. The results are corrected for detector effects and are compared to the predictions of various Monte Carlo event generator models which simulate the full hadronic final state.