Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton--lead collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=5.02$ TeV with the ATLAS detector

Abstract

The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 $\mu$b${}^{-1}$ of proton--lead collisions at a nucleon--nucleon centre-of-mass energy of $\sqrt{s_{{}_{\mathrm{NN}}}}=5.02$ TeV using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The $p$+Pb collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the $p$+Pb collision have been carried out using the Glauber model as well as two Glauber--Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon--nucleon collisions in the modelling of the initial state of $p$+Pb collisions.

28 pages plus author list + cover pages (46 pages total), 14 figures, 4 tables, submitted to EPJC, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2012-15/

References in corpus (14)

• PYTHIA 6.4 Physics and Manual
• Parton distributions for the LHC
• Glauber Modeling in High Energy Nuclear Collisions
• Observation of long-range near-side angular correlations in proton-lead collisions at the LHC
• On the Strongly-Interacting Low-Viscosity Matter Created in Relativistic Nuclear Collisions
• Phobos results on charged particle multiplicity and pseudorapidity distributions in Au+Au, Cu+Cu, d+Au, and p+p collisions at ultra-relativistic energies
• Centrality dependence of particle production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV
• Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
• Explanation of systematics of CMS p+Pb high multiplicity di-hadron data at ${\sqrt{s}}_{\mathrm{NN}}=5.02$ TeV
• Measurement of charged-particle spectra in Pb+Pb collisions at $\sqrt{s_{\mathsf{NN}}}=2.76$ TeV with the ATLAS detector at the LHC
• The PHOBOS Glauber Monte Carlo
• CGC predictions for p+A collisions at the LHC and signature of QCD saturation
• A neural network clustering algorithm for the ATLAS silicon pixel detector
• Centrality dependence of charged hadron production in deuteron+gold and nucleon+gold collisions at sqrt(s_NN)=200 GeV

Cited by in corpus (58)

• Robust Independent Validation of Experiment and Theory: Rivet version 3
• One fluid to rule them all: viscous hydrodynamic description of event-by-event central p+p, p+Pb and Pb+Pb collisions at $\sqrt{s}=5.02$ TeV
• Evidence of strong proton shape fluctuations from incoherent diffraction
• The Muon Puzzle in cosmic-ray induced air showers and its connection to the Large Hadron Collider
• Revealing proton shape fluctuations with incoherent diffraction at high energy
• Experimental overview on small collision systems at the LHC
• Collectivity and electromagnetic radiation in small systems
• Measurements of long-range azimuthal anisotropies and associated Fourier coefficients for $pp$ collisions at $\sqrt{s}=5.02$ and $13$ TeV and $p$+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with the ATLAS detector
• Measurement of quarkonium production in proton--lead and proton--proton collisions at $5.02$ $\mathrm{TeV}$ with the ATLAS detector
• Event Generators for High-Energy Physics Experiments
• Longitudinal dynamics and particle production in relativistic nuclear collisions
• $Z$ boson production in $p+$Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV measured with the ATLAS detector
• Transverse momentum, rapidity, and centrality dependence of inclusive charged-particle production in $\sqrt{s_{NN}}=5.02$ TeV p+Pb collisions measured by the ATLAS experiment
• Progress in the Glauber model at collider energies
• Two-particle azimuthal correlations in photonuclear ultraperipheral Pb+Pb collisions at 5.02 TeV with ATLAS
• Diffractive and non-diffractive wounded nucleons and final states in pA collisions
• Predictions for Cold Nuclear Matter Effects in $p+$Pb Collisions at $\sqrt{s_{{}_{NN}}}=8.16$ TeV
• Constraints on rapidity-dependent initial conditions from charged particle pseudorapidity densities and two-particle correlations
• Transverse momentum and process dependent azimuthal anisotropies in $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV $p$+Pb collisions with the ATLAS detector
• Collectivity in Ultra-Peripheral Pb+Pb Collisions at the Large Hadron Collider
• Reconstructing the impact parameter of proton-nucleus and nucleus-nucleus collisions
• Predictions for $p+$Pb Collisions at $\sqrt{s_{NN}}=5$ TeV: Comparison with Data
• Measurement of forward-backward multiplicity correlations in lead-lead, proton-lead and proton-proton collisions with the ATLAS detector
• Forward-backward multiplicity fluctuation and longitudinal harmonics in high-energy nuclear collisions
• Global analysis of color fluctuation effects in proton- and deuteron-nucleus collisions at RHIC and the LHC
• Femtoscopy with identified charged pions in proton-lead collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with ATLAS
• Strong constraints on jet quenching in centrality-dependent $p$+Pb collisions at 5.02 TeV from ATLAS
• Exploring the effects of electromagnetic fields and tilted bulk distribution on directed flow of D mesons in small systems
• Consequences of high-$x$ proton size fluctuations in small collision systems at RHIC
• $\gamma$-hadron spectra in p + Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Spin-isospin correlated configurations in complex nuclei and neutron skin effect in W${}^{\pm }$ production in high-energy proton-lead collisions
• Measurement of the dependence of transverse energy production at large pseudorapidity on the hard-scattering kinematics of proton-proton collisions at $\sqrt{s}=2.76$ TeV with ATLAS
• Modification of ${\chi }_{c1}$(3872) and $\psi$(2$S$) production in $p$Pb collisions at $\sqrt{s_{NN}}=8.16$ TeV
• System-size dependence of the charged-particle pseudorapidity density at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV for pp, p-Pb, and Pb-Pb collisions
• Pseudorapidity distributions of charged particles in pp($\overline{\mathrm{p}}$), p(d)A and AA collisions using Tsallis thermodynamics
• Revealing minijet dynamics via centrality dependence of the double parton interactions in proton-nucleus interactions
• Multiplicity and pseudorapidity density distributions of charged particles produced in pp, pA and AA collisions at RHIC \& LHC energies
• A spatially constrained QCD colour reconnection in pp, pA, and AA collisions in the PYTHIA8/Angantyr model
• Family of New Exact Solutions for Longitudinally Expanding Ideal Fluids
• Particle multiplicities in the central region of high-energy collisions from $k_T$-factorization with running coupling corrections
• Longitudinal correlations from fluctuating strings in Pb-Pb, p-Pb, and p-p collisions
• Mapping color fluctuations in the photon in ultraperipheral heavy ion collisions at the Large Hadron Collider
• Measurement of the centrality dependence of the dijet yield in $p$+Pb collisions at $\sqrt{s_{{}_{\text{NN}}}}$ = 8.16 TeV with the ATLAS detector
• Initial conditions of bulk matter in ultrarelativistic nuclear collisions
• Selection bias effects on high-$p_{\mathrm{T}}$ yield and correlation measurements in Oxygen+Oxygen collisions
• Longitudinal asymmetry and its effect on pseudorapidity distributions in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV
• Multiplicity fluctuations and correlations in 5.02 TeV p+Pb collisions at zero impact parameter
• Inclusive photon production at forward rapidities in pp and p$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• PISTA: Posterior Ion STAcking
• Relativistic diffusion model for hadron production in p-Pb collisions at the LHC
• Hard processes in small systems
• Four-jet production via double parton scattering in $pA$ collisions at the LHC
• Rapidity Distributions of Hadrons in Proton-Nucleus Collisions
• Femtoscopic measurements in $p$+Pb collisions at $\sqrt{s_{{}_{\text{NN}}}}=5.02$~TeV with ATLAS at the LHC
• Multiplicity fluctuations and rapidity correlations in ultracentral proton-nucleus collisions
• Electroweak bosons in Pb+Pb and p+Pb collisions from ATLAS
• Multiparton interactions: From pp to pA
• A background for thermal photons in heavy ion collisions