Measurement of the nuclear modification factor of $b$-jets in 5.02 TeV Pb+Pb collisions with the ATLAS detector

Abstract

This paper presents a measurement of $b$-jet production in Pb+Pb and $pp$ collisions at $\sqrt{s_{{}_{\text{NN}}}}=5.02$ TeV with the ATLAS detector at the LHC. The measurement uses 260 ${\text{pb}}^{-1}$ of $pp$ collisions collected in 2017 and 1.4 ${\text{nb}}^{-1}$ of Pb+Pb collisions collected in 2018. In both collision systems, jets are reconstructed via the anti-$k_t$ algorithm. The $b$-jets are identified from a sample of jets containing muons from the semileptonic decay of $b$-quarks using template fits of the muon momentum relative to the jet axis. In $pp$ collisions, $b$-jets are reconstructed for radius parameters $R=0.2$ and $R=0.4$, and only $R=0.2$ jets are used in Pb+Pb collisions. For comparison, inclusive $R=0.2$ jets are also measured using 1.7 ${\text{nb}}^{-1}$ of Pb+Pb collisions collected in 2018 and the same $pp$ collision data as the $b$-jet measurement. The nuclear modification factor, $R_{\text{AA}}$, is calculated for both $b$-jets and inclusive jets with $R=0.2$ over the transverse momentum range of 80--290 GeV. The nuclear modification factor for $b$-jets decreases from peripheral to central collisions. The ratio of the $b$-jet $R_{\text{AA}}$ to inclusive jet $R_{\text{AA}}$ is also presented and suggests that the $R_{\text{AA}}$ for $b$-jets is larger than that for inclusive jets in central Pb+Pb collisions. The measurements are compared with theoretical calculations and suggest a role for mass and colour-charge effects in partonic energy loss in heavy-ion collisions.

arXiv comment29 pages, 11 figures, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2018-24/

References in corpus (60)

• The anti-k_t jet clustering algorithm
• An Introduction to PYTHIA 8.2
• FastJet user manual
• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• Herwig++ Physics and Manual
• Parton distributions with LHC data
• The ATLAS Simulation Infrastructure
• Glauber Modeling in High Energy Nuclear Collisions
• Herwig 7.0 / Herwig++ 3.0 Release Note
• Heavy Ion Collisions: The Big Picture, and the Big Questions
• Heavy quark colorimetry of QCD matter
• Muon reconstruction performance of the ATLAS detector in proton--proton collision data at $\sqrt{s}$=13 TeV
• Energy Loss and Flow of Heavy Quarks in Au+Au Collisions at sqrt(s_NN) = 200 GeV
• Production and Integration of the ATLAS Insertable B-Layer
• Jet energy measurement with the ATLAS detector in proton-proton collisions at sqrt(s) = 7 TeV
• Luminosity determination in pp collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector at the LHC
• Elastic, Inelastic, and Path Length Fluctuations in Jet Tomography
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2018
• Jet energy scale measurements and their systematic uncertainties in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Jet energy measurement and its systematic uncertainty in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector
• ATLAS data quality operations and performance for 2015-2018 data-taking
• Performance of the ATLAS muon triggers in Run 2
• Suppression of non-prompt J/psi, prompt J/psi, and Y(1S) in PbPb collisions at sqrt(sNN) = 2.76 TeV
• Colour reconnections in Herwig++
• Jet energy resolution in proton-proton collisions at sqrt(s) = 7 TeV recorded in 2010 with the ATLAS detector
• Improved version of the PHOBOS Glauber Monte Carlo
• Nuclear modification factor of D${}^0$ mesons in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV
• Measurement of the nuclear modification factor for inclusive jets in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with the ATLAS detector
• Operation of the ATLAS trigger system in Run 2
• Open Heavy-Flavor Production in Heavy-Ion Collisions
• Suppression and azimuthal anisotropy of prompt and nonprompt J/psi production in PbPb collisions at sqrt(s[NN]) = 2.76 TeV
• A linearized Boltzmann--Langevin model for heavy quark transport in hot and dense QCD matter
• Measurement of b-hadron fractions in 13 TeV pp collisions
• Centrality and transverse momentum dependence of $D^0$-meson production at mid-rapidity in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=200\mathrm{GeV}$
• Evidence of b-jet quenching in PbPb collisions at sqrt(s[NN]) = 2.76 TeV
• Prompt and non-prompt $J/\psi$ and $\psi (2\mathrm{S})$ suppression at high transverse momentum in 5.02 TeV Pb+Pb collisions with the ATLAS experiment
• Measurement of the B+/- meson nuclear modification factor in PbPb collisions at sqrt(s[NN]) = 5.02 TeV
• Measurement of the azimuthal anisotropy of charged particles produced in $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV Pb+Pb collisions with the ATLAS detector
• Measurements of inclusive jet spectra in pp and central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Prompt D${}^0$, D${}^{+}$, and D${}^{\ast +}$ production in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Measurement of jet fragmentation in Pb+Pb and $pp$ collisions at $\sqrt{s_{NN}}=5.02$ TeV with the ATLAS detector
• Interpreting Single Jet Measurements in Pb+Pb Collisions at the LHC
• Measurement of photon-jet transverse momentum correlations in 5.02 TeV Pb+Pb and $pp$ collisions with ATLAS
• Inclusive b-jet production in pp collisions at sqrt(s)=7 TeV
• DREENA-B framework: first predictions of $R_{AA}$ and $v_2$ within dynamical energy loss formalism in evolving QCD medium
• Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
• First measurement of large area jet transverse momentum spectra in heavy-ion collisions
• Determination of heavy quark non-perturbative parameters from spectral moments in semileptonic B decays
• A modified-Boltzmann approach for modeling the hot QCD medium-induce splitting vertices in the deep LPM region
• Single electron yields from semileptonic charm and bottom hadron decays in Au$+$Au collisions at $\sqrt{s_{NN}}=200$ GeV
• Studies of beauty suppression via nonprompt D${}^0$ mesons in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV
• Inclusive b-hadron production cross section with muons in pp collisions at sqrt(s) = 7 TeV
• Determination of jet calibration and energy resolution in proton-proton collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector
• Measurement of angular and momentum distributions of charged particles within and around jets in Pb+Pb and $pp$ collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with the ATLAS detector
• Configuration and performance of the ATLAS $b$-jet triggers in Run 2
• Transverse Momentum Balance and Angular Distribution of $b\bar{b}$ Dijets in Pb+Pb collisions
• Inclusive heavy flavor jet production with semi-inclusive jet functions: from proton to heavy-ion collisions
• Studies of charm quark diffusion inside jets using PbPb and pp collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV
• Measurement of $b$-quark fragmentation properties in jets using the decay $B^{\pm }\to J/\psi K^{\pm }$ in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Production of muons from heavy-flavour hadron decays at high transverse momentum in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ and 2.76 TeV

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