Measurements of the suppression and correlations of dijets in Xe+Xe collisions at $\sqrt{s_{NN}}$ = 5.44 TeV

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abeling, K. ; et al.
Phys.Rev.C 108 (2023) 024906, 2023.
Inspire Record 2630510 DOI 10.17182/hepdata.139684

Measurements of the suppression and correlations of dijets is performed using 3 $\mu$b$^{-1}$ of Xe+Xe data at $\sqrt{s_{\mathrm{NN}}} = 5.44$ TeV collected with the ATLAS detector at the LHC. Dijets with jets reconstructed using the $R=0.4$ anti-$k_t$ algorithm are measured differentially in jet $p_{\text{T}}$ over the range of 32 GeV to 398 GeV and the centrality of the collisions. Significant dijet momentum imbalance is found in the most central Xe+Xe collisions, which decreases in more peripheral collisions. Results from the measurement of per-pair normalized and absolutely normalized dijet $p_{\text{T}}$ balance are compared with previous Pb+Pb measurements at $\sqrt{s_{\mathrm{NN}}} =5.02$ TeV. The differences between the dijet suppression in Xe+Xe and Pb+Pb are further quantified by the ratio of pair nuclear-modification factors. The results are found to be consistent with those measured in Pb+Pb data when compared in classes of the same event activity and when taking into account the difference between the center-of-mass energies of the initial parton scattering process in Xe+Xe and Pb+Pb collisions. These results should provide input for a better understanding of the role of energy density, system size, path length, and fluctuations in the parton energy loss.

62 data tables

The centrality intervals in Xe+Xe collisions and their corresponding TAA with absolute uncertainties.

The centrality intervals in Xe+Xe and Pb+Pb collisions for matching SUM ET FCAL intervals and respective TAA values for Xe+Xe collisions.

The performance of the jet energy scale (JES) for jets with $|y| < 2.1$ evaluated as a function of pT_truth in different centrality bins. Simulated hard scatter events were overlaid onto events from a dedicated sample of minimum-bias Xe+Xe data.

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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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Version 2
Search for heavy resonances decaying into a $Z$ or $W$ boson and a Higgs boson in final states with leptons and $b$-jets in $139~$fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=13~$TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
JHEP 06 (2023) 016, 2023.
Inspire Record 2104697 DOI 10.17182/hepdata.111122

This article presents a search for new resonances decaying into a $Z$ or $W$ boson and a 125 GeV Higgs boson $h$, and it targets the $\nu\bar{\nu}b\bar{b}$, $\ell^+\ell^-b\bar{b}$, or $\ell^{\pm}{\nu}b\bar{b}$ final states, where $\ell=e$ or $\mu$, in proton-proton collisions at $\sqrt{s}=13$ TeV. The data used correspond to a total integrated luminosity of 139 fb$^{-1}$ collected by the ATLAS detector during Run 2 of the LHC at CERN. The search is conducted by examining the reconstructed invariant or transverse mass distributions of $Zh$ or $Wh$ candidates for evidence of a localised excess in the mass range from 220 GeV to 5 TeV. No significant excess is observed and 95% confidence-level upper limits between 1.3 pb and 0.3 fb are placed on the production cross section times branching fraction of neutral and charged spin-1 resonances and CP-odd scalar bosons. These limits are converted into constraints on the parameter space of the Heavy Vector Triplet model and the two-Higgs-doublet model.

132 data tables

Acceptance * reconstruction efficiency for the P P --> Zprime --> Zh --> vvbb/cc signals in the 0-lepton channel.

Acceptance * reconstruction efficiency for the P P --> Zprime --> Zh --> vvbb/cc signals in the 0-lepton channel.

Acceptance * reconstruction efficiency for the P P --> Zprime --> Zh --> llbb/cc signals in the 2-lepton channel.

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Strong constraints on jet quenching in centrality-dependent $p$+Pb collisions at 5.02 TeV from ATLAS

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Phys.Rev.Lett. 131 (2023) 072301, 2023.
Inspire Record 2090791 DOI 10.17182/hepdata.130943

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including $pp$ and $p$+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36 nb$^{-1}$ of $p$+Pb and 3.6 pb$^{-1}$ of $pp$ collisions at 5.02 TeV. The yields of charged hadrons with $p_\mathrm{T}^\mathrm{ch} >0.5$ GeV near and opposite in azimuth to jets with $p_\mathrm{T}^\mathrm{jet} > 30$ or $60$ GeV, and the ratios of these yields between $p$+Pb and $pp$ collisions, $I_{p\mathrm{Pb}}$, are reported. The collision centrality of $p$+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The $I_{p\mathrm{Pb}}$ values are consistent with unity within a few percent for hadrons with $p_\mathrm{T}^\mathrm{ch} >4$ GeV at all centralities. These data provide new, strong constraints which preclude almost any parton energy loss in central $p$+Pb collisions.

8 data tables

The per-jet charged particle yield in pPb and pp collisions for hadrons near a $p_{T}^{\textrm{jet}} > 30~\textrm{GeV}$ jet ($\Delta\phi_{\textrm{ch,jet}} < \pi/8$).

The per-jet charged particle yield in pPb and pp collisions for hadrons opposite to a $p_{T}^{\textrm{jet}} > 30~\textrm{GeV}$ jet ($\Delta\phi_{\textrm{ch,jet}} > 7\pi/8$).

The per-jet charged particle yield in pPb and pp collisions for hadrons near a $p_{T}^{\textrm{jet}} > 60~\textrm{GeV}$ jet ($\Delta\phi_{\textrm{ch,jet}} < \pi/8$).

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Measurements of the suppression and correlations of dijets in Pb+Pb collisions at $\sqrt{s_{_\text{NN}}}$ = 5.02 TeV

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Phys.Rev.C 107 (2023) 054908, 2023.
Inspire Record 2075431 DOI 10.17182/hepdata.145875

Studies of the correlations of the two highest transverse momentum (leading) jets in individual Pb+Pb collision events can provide information about the mechanism of jet quenching by the hot and dense matter created in such collisions. In Pb+Pb and pp collisions at $\sqrt{s_{_\text{NN}}}$ = 5.02 TeV, measurements of the leading dijet transverse momentum ($p_{\mathrm{T}}$) correlations are presented. Additionally, measurements in Pb+Pb collisions of the dijet pair nuclear modification factors projected along leading and subleading jet $p_{\mathrm{T}}$ are made. The measurements are performed using the ATLAS detector at the LHC with 260 pb$^{-1}$ of pp data collected in 2017 and 2.2 nb$^{-1}$ of Pb+Pb data collected in 2015 and 2018. An unfolding procedure is applied to the two-dimensional leading and subleading jet $p_{\mathrm{T}}$ distributions to account for experimental effects in the measurement of both jets. Results are provided for dijets with leading jet $p_{\mathrm{T}}$ greater than 100 GeV. Measurements of the dijet-yield-normalized $x_{\mathrm{J}}$ distributions in Pb+Pb collisions show an increased fraction of imbalanced jets compared to pp collisions; these measurements are in agreement with previous measurements of the same quantity at 2.76 TeV in the overlapping kinematic range. Measurements of the absolutely-normalized dijet rate in Pb+Pb and pp collisions are also presented, and show that balanced dijets are significantly more suppressed than imbalanced dijets in Pb+Pb collisions. It is observed in the measurements of the pair nuclear modification factors that the subleading jets are significantly suppressed relative to leading jets with $p_{\mathrm{T}}$ between 100 and 316 GeV for all centralities in Pb+Pb collisions.

23 data tables

absolutely normalized dijet cross sections from pp collisions

absolutely normalized dijet yields scaled by 1/<TAA> in 0-10% central PbPb collisions

absolutely normalized dijet yields scaled by 1/<TAA> in 10-20% central PbPb collisions

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Correlations between flow and transverse momentum in Xe+Xe and Pb+Pb collisions at the LHC with the ATLAS detector: a probe of the heavy-ion initial state and nuclear deformation

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Phys.Rev.C 107 (2023) 054910, 2023.
Inspire Record 2075412 DOI 10.17182/hepdata.139082

The correlations between flow harmonics $v_n$ for $n=2$, 3 and 4 and mean transverse momentum $[p_\mathrm{T}]$ in $^{129}$Xe+$^{129}$Xe and $^{208}$Pb+$^{208}$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.44$ TeV and 5.02 TeV, respectively, are measured using charged particles with the ATLAS detector. The correlations are sensitive to the shape and size of the initial geometry, nuclear deformation, and initial momentum anisotropy. The effects from non-flow and centrality fluctuations are minimized, respectively, via a subevent cumulant method and event activity selection based on particle production in the very forward rapidity. The results show strong dependences on centrality, harmonic number $n$, $p_{\mathrm{T}}$ and pseudorapidity range. Current models describe qualitatively the overall centrality- and system-dependent trends but fail to quantitatively reproduce all the data. In the central collisions, where models generally show good agreement, the $v_2$-$[p_\mathrm{T}]$ correlations are sensitive to the triaxiality of the quadruple deformation. The comparison of model to the Pb+Pb and Xe+Xe data suggests that the $^{129}$Xe nucleus is a highly deformed triaxial ellipsoid that is neither a prolate nor an oblate shape. This provides strong evidence for a triaxial deformation of $^{129}$Xe nucleus using high-energy heavy-ion collision.

445 data tables

$\rho_{2}$ Standard method, for Pb+Pb 5.02 TeV, $|\eta|$<2.5, 0.5< $p_{T}$ <5.0 GeV vs $\Sigma E_{T}$ based Centrality

$\rho_{2}$ Two_subevent method, for Pb+Pb 5.02 TeV, $|\eta|$<2.5, 0.5< $p_{T}$ <5.0 GeV vs $\Sigma E_{T}$ based Centrality

$\rho_{2}$ Three_subevent method, for Pb+Pb 5.02 TeV, $|\eta|$<2.5, 0.5< $p_{T}$ <5.0 GeV vs $\Sigma E_{T}$ based Centrality

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Measurement of $J/\psi$ production cross-sections in $pp$ collisions at $\sqrt{s}=5$ TeV

The LHCb collaboration Aaij, R. ; Abdelmotteleb, A.S.W. ; Beteta, C. Abellán ; et al.
JHEP 11 (2021) 181, 2021.
Inspire Record 1915030 DOI 10.17182/hepdata.115512

The production cross-sections of $J/\psi$ mesons in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=5$ TeV are measured using a data sample corresponding to an integrated luminosity of $9.13\pm0.18~\text{pb}^{-1}$, collected by the LHCb experiment. The cross-sections are measured differentially as a function of transverse momentum, $p_{\text{T}}$, and rapidity, $y$, and separately for $J/\psi$ mesons produced promptly and from beauty hadron decays (nonprompt). With the assumption of unpolarised $J/\psi$ mesons, the production cross-sections integrated over the kinematic range $0<p_{\text{T}}<20~\text{GeV}/c$ and $2.0<y<4.5$ are $8.154\pm0.010\pm0.283~\mu\text{b}$ for prompt $J/\psi$ mesons and $0.820\pm0.003\pm0.034~\mu\text{b}$ for nonprompt $J/\psi$ mesons, where the first uncertainties are statistical and the second systematic. These cross-sections are compared with those at $\sqrt{s}=8$ TeV and $13$ TeV, and are used to update the measurement of the nuclear modification factor in proton-lead collisions for $J/\psi$ mesons at a centre-of-mass energy per nucleon pair of $\sqrt{s_{\text{NN}}}=5$ TeV. The results are compared with theoretical predictions.

20 data tables

Double-differential production cross-sections for prompt $J/\psi$ mesons in ($p_\text{T},y$) intervals. The first uncertainties are statistical, the second are correlated systematic uncertainties shared between intervals, the third are uncorrelated systematic uncertainties, and the last are correlated between $p_\text{T}$ intervals and uncorrelated between $y$ intervals.

Double-differential production cross-sections for nonprompt $J/\psi$ mesons in ($p_\text{T},y$) intervals. The first uncertainties are statistical, the second are correlated systematic uncertainties shared between intervals, the third are uncorrelated systematic uncertainties, and the last are correlated between $p_\text{T}$ intervals and uncorrelated between $y$ intervals.

Single-differential production cross-sections for prompt $J/\psi$ mesons as a function of $p_\text{T}$. The first uncertainties are statistical, the second are correlated systematic uncertainties shared between intervals, and the last are uncorrelated systematic uncertainties.

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Observation of $Z$ production in proton-lead collisions at LHCb

The LHCb collaboration Aaij, R. ; Adeva, B. ; Adinolfi, M. ; et al.
JHEP 09 (2014) 030, 2014.
Inspire Record 1300150 DOI 10.17182/hepdata.64260

The first observation of $Z$ boson production in proton-lead collisions at a centre-of-mass energy per proton-nucleon pair of $\sqrt{s_{NN}}=5~\text{TeV}$ is presented. The data sample corresponds to an integrated luminosity of $1.6~\text{nb}^{-1}$ collected with the LHCb detector. The $Z$ candidates are reconstructed from pairs of oppositely charged muons with pseudorapidities between 2.0 and 4.5 and transverse momenta above $20~\text{GeV}/c$. The invariant dimuon mass is restricted to the range $60-120~\text{GeV}/c^2$. The $Z$ production cross-section is measured to be \begin{eqnarray*} \sigma_{Z\to\mu^+\mu^-}(\text{fwd})&=&13.5^{+5.4}_{-4.0}\text{(stat.)}\pm1.2\text{(syst.)}~\text{nb} \end{eqnarray*} in the direction of the proton beam and \begin{eqnarray*} \sigma_{Z\to\mu^+\mu^-}(\text{bwd}) & =&10.7^{+8.4}_{-5.1}\text{(stat.)}\pm1.0\text{(syst.)}~\text{nb} \end{eqnarray*} in the direction of the lead beam, where the first uncertainty is statistical and the second systematic.

2 data tables

The measured Z production cross-sections in proton-lead collisions, measured in the fiducial region defined in the table, in the forward and backward directions. The statistical uncertainty is defined as the 68% confidence interval with symmetric coverage assuming that the number of candidates follows a Poisson distribution.

The forward-backward ratio measured in the overlap region 2.5 < ABS(YRAP) < 4.0. The first uncertainty is statistical, defined as the 68% confidence interval with symmetric coverage. The second uncertainty is systematic and includes the uncertainty on the acceptance correction factor, BETA, for the difference in the detector acceptance of the muons between the forward and backward directions.


Inclusive J/psi production in pp collisions at sqrt(s) = 2.76 TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.
Phys.Lett.B 718 (2012) 295-306, 2012.
Inspire Record 1094079 DOI 10.17182/hepdata.62231

The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.

4 data tables

Double differential J/$\psi$ production cross section at $\sqrt{s}=2.76$ TeV. The first uncertainty is statistical, the second one is $p_{\rm T}$-coorelated, the third one is uncorrelated. Polarization-related uncertainties are not included.

The $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

the $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

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Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s_{(NN)}) = 2.76 TeV

The ALICE collaboration Aamodt, K. ; Abelev, B. ; Abrahantes Quintana, A. ; et al.
Phys.Rev.Lett. 107 (2011) 032301, 2011.
Inspire Record 900651 DOI 10.17182/hepdata.62026

We report on the first measurement of the triangular $v_3$, quadrangular $v_4$, and pentagonal $v_5$ charged particle flow in Pb-Pb collisions at 2.76 TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow $v_2$ and $v_3$ have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

36 data tables

v2{SP} (red filled circles).

v3{SP} (blue filled squares).

v4{SP} (purprle stars).

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