Higher-order moments of the elliptic flow distribution in PbPb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 2024 (2024) 106, 2024.
Inspire Record 2724506 DOI 10.17182/hepdata.132638

The hydrodynamic flow-like behavior of charged hadrons in high-energy lead-lead collisions is studied through multiparticle correlations. The elliptic anisotropy values based on different orders of multiparticle cumulants, $v_{2}\{2k\}$, are measured up to the tenth order ($k$ = 5) as functions of the collision centrality at a nucleon-nucleon center-of-mass energy of $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV. The data were recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 0.607 nb$^{-1}$. A hierarchy is observed between the coefficients, with $v_{2}\{2\} > v_{2}\{4\} \gtrsim v_{2}\{6\} \gtrsim v_{2}\{8\} \gtrsim v_{2}\{10\}$. Based on these results, centrality-dependent moments for the fluctuation-driven event-by-event $v_{2}$ distribution are determined, including the skewness, kurtosis and, for the first time, superskewness. Assuming a hydrodynamic expansion of the produced medium, these moments directly probe the initial-state geometry in high-energy nucleus-nucleus collisions.

8 data tables

The $v_2\{2k\}$ ($k = 1, ..., 5$) values as functions of centrality in PbPb collisions at $\sqrt{s_{NN}}=5.02~\textrm{Te}\textrm{V}$. The measurement is performed with charged particles within the acceptance region.

The relative differences $(v_2\{2k\}-v_2\{10\})/v_2\{10\}$ ($k = 1, ..., 4$) as functions of centrality in PbPb collisions at $\sqrt{s_{NN}}=5.02~\textrm{Te}\textrm{V}$. The measurement is performed with charged particles within the acceptance region.

The $h_1$ and the $h_2$ hydrodynamic probes as functions of centrality in PbPb collisions at $\sqrt{s_{NN}}=5.02~\textrm{Te}\textrm{V}$. The measurement is performed with charged particles within the acceptance region.

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Multiplicity and transverse momentum dependence of charge-balance functions in pPb and PbPb collisions at LHC energies

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
CMS-HIN-21-017, 2023.
Inspire Record 2679254 DOI 10.17182/hepdata.135972

Measurements of the charge-dependent two-particle angular correlation function in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV and lead-lead (PbPb) collisions at$\sqrt{s_\mathrm{NN}}$ = 5.02 TeV are reported. The pPb and PbPb datasets correspond to integrated luminosities of 186\nbinv and 0.607 nb$^{-1}$, respectively, and were collected using the CMS detector at the CERN LHC. The charge-dependent correlations are characterized by balance functions of same- and opposite-sign particle pairs. The balance functions, which contain information about the creation time of charged particle pairs and the development of collectivity, are studied as functions of relative pseudorapidity ($\Delta \eta$) and relative azimuthal angle ($\Delta \phi$), for various multiplicity and transverse momentum ($p_\mathrm{T}$) intervals. A multiplicity dependence of the balance function is observed in $\Delta \eta$ and $\Delta \phi$ for both systems. The width of the balance functions decreases towards high-multiplicity collisions in the momentum region $\lt$2 GeV, for pPb and PbPb results. No multiplicity dependence is observed at higher transverse momentum. The data are compared with HYDJET, HIJING and AMPT generator predictions, none of which capture completely the multiplicity dependence seen in the data.

56 data tables

$\Delta\eta$ projection of balance function in low $p_{T}$ in 0-10% centrality

$\Delta\eta$ projection of balance function in low $p_{T}$ in 30-40% centrality

$\Delta\eta$ projection of balance function in low $p_{T}$ in 70-80% centrality

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Two-particle Bose-Einstein correlations and their Lévy parameters in PbPb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.C 109 (2024) 024914, 2024.
Inspire Record 2670243 DOI 10.17182/hepdata.134676

Two-particle Bose-Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV. The data sample, containing 4.27 $\times$$10^{9}$ minimum bias events corresponding to an integrated luminosity of 0.607 nb$^{-1}$, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a Lévy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the Lévy index or shape parameter ($\alpha$), the Lévy scale parameter ($R$), and the correlation strength parameter ($\lambda$). The source shape, characterized by $\alpha$, is found to be neither Cauchy nor Gaussian, implying the need for a full Lévy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a hydrodynamical scaling is observed for the Lévy $R$ parameter. The $\lambda$ parameter is studied in terms of the core-halo model.

12 data tables

The correlation function $C_2(q)$ of negatively charged hadron pairs with $1.00<K_{\mathrm{T}}<1.05$ GeV/$c$ in the 10-20% centrality bin.

The double-ratio correlation function $DR(q)$ of negatively charged hadron pairs with $1.30<K_{\mathrm{T}}<1.35$ GeV/$c$ in the 20-30% centrality bin.

The two-particle correlation function of negatively charged hadron pairs with $0.9<K_{\mathrm{T}}<1.3$ GeV/$c$ in the 0-100% centrality range, calculated using MC events with (Reco) and without (Gen) detector reconstruction.

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Charged-hadron production in $pp$, $p$+Pb, Pb+Pb, and Xe+Xe collisions at $\sqrt{s_{_\text{NN}}}=5$ TeV with the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
JHEP 07 (2023) 074, 2023.
Inspire Record 2601282 DOI 10.17182/hepdata.135676

This paper presents measurements of charged-hadron spectra obtained in $pp$, $p$+Pb, and Pb+Pb collisions at $\sqrt{s}$ or $\sqrt{s_{_\text{NN}}}=5.02$ TeV, and in Xe+Xe collisions at $\sqrt{s_{_\text{NN}}}=5.44$ TeV. The data recorded by the ATLAS detector at the LHC have total integrated luminosities of 25 pb${}^{-1}$, 28 nb${}^{-1}$, 0.50 nb${}^{-1}$, and 3 $\mu$b${}^{-1}$, respectively. The nuclear modification factors $R_{p\text{Pb}}$ and $R_\text{AA}$ are obtained by comparing the spectra in heavy-ion and $pp$ collisions in a wide range of charged-particle transverse momenta and pseudorapidity. The nuclear modification factor $R_{p\text{Pb}}$ shows a moderate enhancement above unity with a maximum at $p_{\mathrm{T}} \approx 3$ GeV; the enhancement is stronger in the Pb-going direction. The nuclear modification factors in both Pb+Pb and Xe+Xe collisions feature a significant, centrality-dependent suppression. They show a similar distinct $p_{\mathrm{T}}$-dependence with a local maximum at $p_{\mathrm{T}} \approx 2$ GeV and a local minimum at $p_{\mathrm{T}} \approx 7$ GeV. This dependence is more distinguishable in more central collisions. No significant $|\eta|$-dependence is found. A comprehensive comparison with several theoretical predictions is also provided. They typically describe $R_\text{AA}$ better in central collisions and in the $p_{\mathrm{T}}$ range from about 10 to 100 GeV.

140 data tables

- - - - - - - - - - - - - - - - - - - - <br><b>charged-hadron spectra:</b> <br><i>pp reference:</i>&nbsp;&nbsp; <a href="?version=1&table=Table1">for p+Pb</a>&nbsp;&nbsp; <a href="?version=1&table=Table10">for Pb+Pb</a>&nbsp;&nbsp; <a href="?version=1&table=Table19">for Xe+Xe</a>&nbsp;&nbsp; <br><i>p+Pb:</i>&nbsp;&nbsp; <a href="?version=1&table=Table2">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table3">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table4">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table5">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table6">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table7">40-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table8">60-90%</a>&nbsp;&nbsp; <a href="?version=1&table=Table9">0-90%</a>&nbsp;&nbsp; <br><i>Pb+Pb:</i>&nbsp;&nbsp; <a href="?version=1&table=Table11">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table12">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table13">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table14">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table15">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table16">40-50%</a>&nbsp;&nbsp; <a href="?version=1&table=Table17">50-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table18">60-80%</a>&nbsp;&nbsp; <br><i>Xe+Xe:</i>&nbsp;&nbsp; <a href="?version=1&table=Table20">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table21">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table22">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table23">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table24">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table25">40-50%</a>&nbsp;&nbsp; <a href="?version=1&table=Table26">50-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table27">60-80%</a>&nbsp;&nbsp; </br>- - - - - - - - - - - - - - - - - - - - <br><b>nuclear modification factors (p<sub>T</sub>):</b> <br><i>R<sub>pPb</sub>:</i>&nbsp;&nbsp; <a href="?version=1&table=Table28">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table29">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table30">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table31">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table32">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table33">40-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table34">60-90%</a>&nbsp;&nbsp; <a href="?version=1&table=Table35">0-90%</a>&nbsp;&nbsp; <br><i>R<sub>AA</sub> (Pb+Pb):</i>&nbsp;&nbsp; <a href="?version=1&table=Table36">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table37">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table38">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table39">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table40">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table41">40-50%</a>&nbsp;&nbsp; <a href="?version=1&table=Table42">50-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table43">60-80%</a>&nbsp;&nbsp; <br><i>R<sub>AA</sub> (Xe+Xe):</i>&nbsp;&nbsp; <a href="?version=1&table=Table44">0-5%</a>&nbsp;&nbsp; <a href="?version=1&table=Table45">5-10%</a>&nbsp;&nbsp; <a href="?version=1&table=Table46">10-20%</a>&nbsp;&nbsp; <a href="?version=1&table=Table47">20-30%</a>&nbsp;&nbsp; <a href="?version=1&table=Table48">30-40%</a>&nbsp;&nbsp; <a href="?version=1&table=Table49">40-50%</a>&nbsp;&nbsp; <a href="?version=1&table=Table50">50-60%</a>&nbsp;&nbsp; <a href="?version=1&table=Table51">60-80%</a>&nbsp;&nbsp; </br>- - - - - - - - - - - - - - - - - - - - <br><b>nuclear modification factors (y*/eta):</b> <br><i>R<sub>pPb</sub>:</i> <br>&nbsp;&nbsp;0-5%:&nbsp;&nbsp; <a href="?version=1&table=Table52">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table53">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table54">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table55">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;5-10%:&nbsp;&nbsp; <a href="?version=1&table=Table56">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table57">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table58">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table59">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;10-20%:&nbsp;&nbsp; <a href="?version=1&table=Table60">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table61">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table62">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table63">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;20-30%:&nbsp;&nbsp; <a href="?version=1&table=Table64">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table65">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table66">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table67">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;30-40%:&nbsp;&nbsp; <a href="?version=1&table=Table68">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table69">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table70">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table71">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;40-60%:&nbsp;&nbsp; <a href="?version=1&table=Table72">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table73">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table74">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table75">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;60-90%:&nbsp;&nbsp; <a href="?version=1&table=Table76">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table77">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table78">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table79">15.1-17.3GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;0-90%:&nbsp;&nbsp; <a href="?version=1&table=Table80">0.66-0.755GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table81">2.95-3.35GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table82">7.65-8.8GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table83">15.1-17.3GeV</a>&nbsp;&nbsp; <br><i>R<sub>AA</sub> (Pb+Pb):</i> <br>&nbsp;&nbsp;0-5%:&nbsp;&nbsp; <a href="?version=1&table=Table84">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table85">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table86">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table87">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;5-10%:&nbsp;&nbsp; <a href="?version=1&table=Table88">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table89">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table90">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table91">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;10-20%:&nbsp;&nbsp; <a href="?version=1&table=Table92">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table93">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table94">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table95">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;20-30%:&nbsp;&nbsp; <a href="?version=1&table=Table96">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table97">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table98">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table99">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;30-40%:&nbsp;&nbsp; <a href="?version=1&table=Table100">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table101">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table102">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table103">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;40-50%:&nbsp;&nbsp; <a href="?version=1&table=Table104">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table105">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table106">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table107">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;50-60%:&nbsp;&nbsp; <a href="?version=1&table=Table108">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table109">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table110">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table111">60-95GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;60-80%:&nbsp;&nbsp; <a href="?version=1&table=Table112">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table113">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table114">20-23GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table115">60-95GeV</a>&nbsp;&nbsp; <br><i>R<sub>AA</sub> (Xe+Xe):</i> <br>&nbsp;&nbsp;0-5%:&nbsp;&nbsp; <a href="?version=1&table=Table116">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table117">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table118">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;5-10%:&nbsp;&nbsp; <a href="?version=1&table=Table119">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table120">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table121">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;10-20%:&nbsp;&nbsp; <a href="?version=1&table=Table122">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table123">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table124">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;20-30%:&nbsp;&nbsp; <a href="?version=1&table=Table125">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table126">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table127">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;30-40%:&nbsp;&nbsp; <a href="?version=1&table=Table128">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table129">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table130">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;40-50%:&nbsp;&nbsp; <a href="?version=1&table=Table131">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table132">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table133">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;50-60%:&nbsp;&nbsp; <a href="?version=1&table=Table134">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table135">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table136">20-23GeV</a>&nbsp;&nbsp; <br>&nbsp;&nbsp;60-80%:&nbsp;&nbsp; <a href="?version=1&table=Table137">1.7-1.95GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table138">6.7-7.65GeV</a>&nbsp;&nbsp; <a href="?version=1&table=Table139">20-23GeV</a>&nbsp;&nbsp; <br>- - - - - - - - - - - - - - - - - - - -

Charged-hadron cross-section in pp collisions. The systematic uncertainties are described in the section 7 of the paper. The total systematic uncertainties are determined by adding the contributions from all relevant sources in quadrature.

Charged-hadron spectrum in the centrality interval 0-5% for p+Pb, divided by &#9001;TPPB&#9002;. The systematic uncertainties are described in the section 7 of the paper. The total systematic uncertainties are determined by adding the contributions from all relevant sources in quadrature.

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Strange hadron collectivity in pPb and PbPb collisions

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 05 (2023) 007, 2023.
Inspire Record 2075415 DOI 10.17182/hepdata.115425

The collective behavior of K$^0_\mathrm{S}$ and $\Lambda/\bar{\Lambda}$ strange hadrons is studied by measuring the elliptic azimuthal anisotropy ($v_2$) using the scalar-product and multiparticle correlation methods. Proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV and lead-lead (PbPb) collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV collected by the CMS experiment at the LHC are investigated. Nonflow effects in the pPb collisions are studied by using a subevent cumulant analysis and by excluding events where a jet with transverse momentum greater than 20\GeV is present. The strange hadron $v_2$ values extracted in \pPb collisions via the four- and six-particle correlation method are found to be nearly identical, suggesting the collective behavior. Comparisons of the pPb and PbPb results for both strange hadrons and charged particles illustrate how event-by-event flow fluctuations depend on the system size.

55 data tables

The elliptic flow $v_2\{4\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

The elliptic flow $v_2\{6\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

The elliptic flow $v_2\{8\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

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Measurement of quark- and gluon-like jet fractions using jet charge in PbPb and pp collisions at 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 07 (2020) 115, 2020.
Inspire Record 1789224 DOI 10.17182/hepdata.88294

The momentum-weighted sum of the electric charges of particles inside a jet, known as jet charge, is sensitive to the electric charge of the particle initiating the parton shower. This paper presents jet charge distributions in $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV lead-lead (PbPb) and proton-proton (pp) collisions recorded with the CMS detector at the LHC. These data correspond to integrated luminosities of 404 $\mu$b$^{-1}$ and 27.4 pb$^{-1}$ for PbPb and pp collisions, respectively. Leveraging the sensitivity of the jet charge to fundamental differences in the electric charges of quarks and gluons, the jet charge distributions from simulated events are used as templates to extract the quark- and gluon-like jet fractions from data. The modification of these jet fractions is examined by comparing pp and PbPb data as a function of the overlap of the colliding Pb nuclei (centrality). This measurement tests the color charge dependence of jet energy loss due to interactions with the quark-gluon plasma. No significant modification between different centrality classes and with respect to pp results is observed in the extracted fractions of quark- and gluon-like jet fractions.

14 data tables

Unfolded jet charge measurements for the $p_{T}$-weighting factor $\kappa = 0.5$ and a minimum track $p_{T}$ of 1 GeV for inclusive jets in pp and PbPb data. The PbPb results are shown for different centrality regions.

The standard deviation of the jet charge distributions with different track $p_{T}$ thresholds and $\kappa$ value of 0.5 for pp collisions and in the various event centrality bins for PbPb collisions compared with the PYTHIA6 prediction.

The standard deviation of the jet charge distributions with different track $p_{T}$ thresholds and $\kappa$ value of 0.3 for pp collisions and in the various event centrality bins for PbPb collisions compared with the PYTHIA6 prediction.

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Measurement of long-range near-side two-particle angular correlations in pp collisions at sqrt(s) = 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 116 (2016) 172302, 2016.
Inspire Record 1397173 DOI 10.17182/hepdata.73192

Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of-mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270 inverse nanobarns. The correlations are studied over a broad range of pseudorapidity (abs(eta) < 2.4) and over the full azimuth (phi) as a function of charged particle multiplicity and transverse momentum (pt). In high-multiplicity events, a long-range (abs(Delta eta) > 2.0), near-side (Delta phi approximately 0) structure emerges in the two-particle Delta eta-Delta phi correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0 < pt < 2.0 GeV/c and an approximately linear increase with the charged particle multiplicity, with an overall correlation strength similar to that found in earlier pp data at sqrt(s) = 7 TeV. The present measurement extends the study of near-side long-range correlations up to charged particle multiplicities of N[ch] approximately 180, a region so far unexplored in pp collisions. The observed long-range correlations are compared to those seen in pp, pPb, and PbPb collisions at lower collision energies.

38 data tables

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 0.1 $<p_{T}<$ 1.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 13 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 0.1 $<p_{T}<$ 1.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 7 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 1.0 $<p_{T}<$ 2.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 13 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

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Measurement of charged jet suppression n Pb-Pb collisions at sqrt(sNN)=2.76TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.
JHEP 03 (2014) 013, 2014.
Inspire Record 1263194 DOI 10.17182/hepdata.62723

A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV is reported. Jets are reconstructed from charged particles using the anti-$k_{\rm T}$ jet algorithm with jet resolution parameters $R$ of $0.2$ and $0.3$ in pseudo-rapidity $|\eta|<0.5$. The transverse momentum $p_{\rm T}$ of charged particles is measured down to $0.15$ GeV/$c$ which gives access to the low $p_{\rm T}$ fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter $R=0.3$ considered in the analysis. The fragmentation bias introduced by selecting jets with a high $p_{\rm T}$ leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with $R=0.2$ and $R=0.3$ is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with $R<0.3$.

30 data tables

Average values of the number of participating nucleons (Npart), number of binary collisions (Ncoll), and the nuclear overlap function (TAA) for the centrality intervals used in the jet analysis.

Charged jet spectra using two cone radius parameters R = 0.2 and 0.3 and a leading track selection of pT > 0.15 GeV, for centrality 0-10%. The two systematic uncertainties correspond to the shape uncertainty and the correlated uncertainty.

Charged jet spectra using two cone radius parameters R = 0.2 and 0.3 and a leading track selection of pT > 0.15 GeV, for centrality 10-30%. The two systematic uncertainties correspond to the shape uncertainty and the correlated uncertainty.

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Measurement of the elliptic anisotropy of charged particles produced in PbPb collisions at nucleon-nucleon center-of-mass energy = 2.76 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.C 87 (2013) 014902, 2013.
Inspire Record 1107659 DOI 10.17182/hepdata.58994

The anisotropy of the azimuthal distributions of charged particles produced in PbPb collisions with a nucleon-nucleon center-of-mass energy of 2.76 TeV is studied with the CMS experiment at the LHC. The elliptic anisotropy parameter defined as the second coefficient in a Fourier expansion of the particle invariant yields, is extracted using the event-plane method, two- and four-particle cumulants, and Lee--Yang zeros. The anisotropy is presented as a function of transverse momentum (pt), pseudorapidity (eta) over a broad kinematic range: 0.3 < pt < 20 GeV, abs(eta) < 2.4, and in 12 classes of collision centrality from 0 to 80%. The results are compared to those obtained at lower center-of-mass energies, and various scaling behaviors are examined. When scaled by the geometric eccentricity of the collision zone, the elliptic anisotropy is found to obey a universal scaling with the transverse particle density for different collision systems and center-of-mass energies.

92 data tables

Measurements of the elliptic anisotropy parameter using the event-plane method, V2(EP) v PT for the centrality range 0-5%.

Measurements of the elliptic anisotropy parameter using the event-plane method, V2(EP) v PT for the centrality range 5-10%.

Measurements of the elliptic anisotropy parameter using the event-plane method, V2(EP) v PT for the centrality range 10-15%.

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Measurement of the azimuthal anisotropy for charged particle production in sqrt(s_NN) = 2.76 TeV lead-lead collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.C 86 (2012) 014907, 2012.
Inspire Record 1093733 DOI 10.17182/hepdata.59488

Differential measurements of charged particle azimuthal anisotropy are presented for lead-lead collisions at sqrt(s_NN) = 2.76 TeV with the ATLAS detector at the LHC, based on an integrated luminosity of approximately 8 mb^-1. This anisotropy is characterized via a Fourier expansion of the distribution of charged particles in azimuthal angle (phi), with the coefficients v_n denoting the magnitude of the anisotropy. Significant v_2-v_6 values are obtained as a function of transverse momentum (0.5<pT<20 GeV), pseudorapidity (|eta|<2.5) and centrality using an event plane method. The v_n values for n>=3 are found to vary weakly with both eta and centrality, and their pT dependencies are found to follow an approximate scaling relation, v_n^{1/n}(pT) \propto v_2^{1/2}(pT). A Fourier analysis of the charged particle pair distribution in relative azimuthal angle (Dphi=phi_a-phi_b) is performed to extract the coefficients v_{n,n}=<cos (n Dphi)>. For pairs of charged particles with a large pseudorapidity gap (|Deta=eta_a-eta_b|>2) and one particle with pT<3 GeV, the v_{2,2}-v_{6,6} values are found to factorize as v_{n,n}(pT^a,pT^b) ~ v_n(pT^a)v_n(pT^b) in central and mid-central events. Such factorization suggests that these values of v_{2,2}-v_{6,6} are primarily due to the response of the created matter to the fluctuations in the geometry of the initial state. A detailed study shows that the v_{1,1}(pT^a,pT^b) data are consistent with the combined contributions from a rapidity-even v_1 and global momentum conservation. A two-component fit is used to extract the v_1 contribution. The extracted v_1 is observed to cross zero at pT\sim1.0 GeV, reaches a maximum at 4-5 GeV with a value comparable to that for v_3, and decreases at higher pT.

209 data tables

The EP Resolution Factor vs. Centrality for n values from2 to 6.

The Chi Reolution Factor vs. Centrality for n values from 2 to 6.

The one-dimensional Delta(PHI) correlation function vs Delta(PHI) for |DETARAP| in the range 2 to 5 summed over all n values from 1 to 6.

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