Version 2
Measurements of the inclusive and differential production cross sections of a top-quark-antiquark pair in association with a $Z$ boson at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Dale Charles ; et al.
CERN-EP-2021-01, 2021.
Inspire Record 1853014 DOI 10.17182/hepdata.100351

Measurements of both the inclusive and differential production cross sections of a top-quark-antiquark pair in association with a $Z$ boson ($t\bar{t}Z$) are presented. The measurements are performed by targeting final states with three or four isolated leptons (electrons or muons) and are based on $\sqrt{s} = 13$ TeV proton-proton collision data with an integrated luminosity of 139 fb$^{-1}$, recorded from 2015 to 2018 with the ATLAS detector at the CERN Large Hadron Collider. The inclusive cross section is measured to be $\sigma_{t\bar{t}Z} = 0.99 \pm 0.05$ (stat.) $\pm 0.08$ (syst.) pb, in agreement with the most precise theoretical predictions. The differential measurements are presented as a function of a number of kinematic variables which probe the kinematics of the $t\bar{t}Z$ system. Both absolute and normalised differential cross-section measurements are performed at particle and parton levels for specific fiducial volumes and are compared with theoretical predictions at different levels of precision, based on a $\chi^{2}/$ndf and $p$-value computation. Overall, good agreement is observed between the unfolded data and the predictions.

76 data tables

The measured $t\bar{t}\text{Z}$ cross-section value and its uncertainty based on the fit results from the combined trilepton and tetralepton channels. The value corresponds to the phase-space region where the difermion mass from the Z boson decay lies in the range $70 < m_{f\bar{f}} < 110$ GeV.

List of relative uncertainties of the measured inclusive $t\bar{t}\text{Z}$ cross section from the combined fit. The uncertainties are symmetrised for presentation and grouped into the categories described in the text. The quadratic sum of the individual uncertainties is not equal to the total uncertainty due to correlations introduced by the fit.

The definitions of the trilepton signal regions: for the inclusive measurement, a combination of the regions with pseudo-continuous $b$-tagging 3$\ell$-Z-1$b$4$j$-PCBT and 3$\ell$-Z-2$b$3$j$-PCBT is used, whereas for the differential measurement, only the region 3$\ell$-Z-2$b$3$j$, with a fixed $b$-tagging WP is employed.

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Production of charged pions, kaons, and (anti-)protons in Pb-Pb and inelastic $pp$ collisions at $\sqrt {s_{NN}}$ = 5.02 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Phys.Rev.C 101 (2020) 044907, 2020.
Inspire Record 1759506 DOI 10.17182/hepdata.104923

Mid-rapidity production of $\pi^{\pm}$, $\rm{K}^{\pm}$ and ($\bar{\rm{p}}$)p measured by the ALICE experiment at the LHC, in Pb-Pb and inelastic pp collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV, is presented. The invariant yields are measured over a wide transverse momentum ($p_{\rm{T}}$) range from hundreds of MeV/$c$ up to 20 GeV/$c$. The results in Pb-Pb collisions are presented as a function of the collision centrality, in the range 0$-$90%. The comparison of the $p_{\rm{T}}$-integrated particle ratios, i.e. proton-to-pion (p/$\pi$) and kaon-to-pion (K/$\pi$) ratios, with similar measurements in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV show no significant energy dependence. Blast-wave fits of the $p_{\rm{T}}$ spectra indicate that in the most central collisions radial flow is slightly larger at 5.02 TeV with respect to 2.76 TeV. Particle ratios (p/$\pi$, K/$\pi$) as a function of $p_{\rm{T}}$ show pronounced maxima at $p_{\rm{T}}$ $\approx$ 3 GeV/$c$ in central Pb-Pb collisions. At high $p_{\rm{T}}$, particle ratios at 5.02 TeV are similar to those measured in pp collisions at the same energy and in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV. Using the pp reference spectra measured at the same collision energy of 5.02 TeV, the nuclear modification factors for the different particle species are derived. Within uncertainties, the nuclear modification factor is particle species independent for high $p_{\rm{T}}$ and compatible with measurements at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV. The results are compared to state-of-the-art model calculations, which are found to describe the observed trends satisfactorily.

17 data tables

$p_{T}$-distributions of pions ($\pi^{+}+\pi^{-}$) measured in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV.

$p_{T}$-distributions of pions ($\pi^{+}+\pi^{-}$) measured in pp collisions at $\sqrt{s}$ = 5.02 TeV.

$p_{T}$-distributions of kaons ($K^{+}+K^{-}$) measured in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV.

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Version 3
Search for electroweak production of charginos and sleptons decaying into final states with two leptons and missing transverse momentum in $\sqrt{s}=13$ TeV $pp$ collisions using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 80 (2020) 123, 2020.
Inspire Record 1750597 DOI 10.17182/hepdata.89413

A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis is based on 139 fb$^{-1}$ of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at $\sqrt{s}=13$ TeV. Three $R$-parity-conserving scenarios where the lightest neutralino is the lightest supersymmetric particle are considered: the production of chargino pairs with decays via either $W$ bosons or sleptons, and the direct production of slepton pairs. The analysis is optimised for the first of these scenarios, but the results are also interpreted in the others. No significant deviations from the Standard Model expectations are observed and limits at 95 % confidence level are set on the masses of relevant supersymmetric particles in each of the scenarios. For a massless lightest neutralino, masses up to 420 GeV are excluded for the production of the lightest-chargino pairs assuming $W$-boson-mediated decays and up to 1 TeV for slepton-mediated decays, whereas for slepton-pair production masses up to 700 GeV are excluded assuming three generations of mass-degenerate sleptons.

154 data tables

- - - - - - - - Overview of HEPData Record - - - - - - - - <br/><br/> <b>Background Fit results:</b> <ul> <li><a href="89413?version=1&table=Backgroundfit1">CRs</a> <li><a href="89413?version=1&table=Backgroundfit2">VRs</a> <li><a href="89413?version=1&table=Backgroundfit5">inclusive DF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit6">inclusive DF-1J SRs</a> <li><a href="89413?version=1&table=Backgroundfit3">inclusive SF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit4">inclusive SF-1J SRs</a> </ul> <b>Kinematic distributions in VRs:</b> <ul> <li><a href="89413?version=1&table=VRkinematics1">$m_{T2}$ in VR-top-low</a> <li><a href="89413?version=1&table=VRkinematics2">$m_{T2}$ in VR-top-high</a> <li><a href="89413?version=1&table=VRkinematics3">$E_T^{miss}$ in VR-WW-0J</a> <li><a href="89413?version=1&table=VRkinematics4">$E_T^{miss}$ in VR-WW-1J</a> <li><a href="89413?version=1&table=VRkinematics5">$E_T^{miss}$ sig in VR-VZ</a> <li><a href="89413?version=1&table=VRkinematics6">$E_T^{miss}$ sig in VR-top-WW</a> </ul> <b>Kinematic distributions in SRs:</b> <ul> <li><a href="89413?version=1&table=SRkinematics1">$m_{T2}$ in SR-SF-0J</a> <li><a href="89413?version=1&table=SRkinematics2">$m_{T2}$ in SR-SF-1J</a> <li><a href="89413?version=1&table=SRkinematics3">$m_{T2}$ in SR-DF-0J</a> <li><a href="89413?version=1&table=SRkinematics4">$m_{T2}$ in SR-DF-1J</a> </ul> <b>Systematic uncertaities:</b> <ul> <li><a href="89413?version=1&table=Systematic uncertainties">dominant systematic uncertainties in the inclusive SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=1&table=Exclusioncontour(obs)1">expected exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)1">observed exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)2">expected exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)2">observed exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)3">expected exclusion contour direct slepton-pair production grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)3">observed exclusion contour direct slepton-pair production grid</a> </ul> <br/><br/><b>AUXILIARY MATERIAL</b><br/> <b>Background Fit in binned SRs:</b> <ul> <li><a href="89413?version=1&table=Backgroundfit7">binned DF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit8">binned DF-1J SRs</a> <li><a href="89413?version=1&table=Backgroundfit9">binned SF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit10">binned SF-1J SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=1&table=Exclusioncontour(obs)4">expected exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)4">observed exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)5">expected exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)5">observed exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)6">expected exclusion contour selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)6">observed exclusion contour selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)7">expected exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)7">observed exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)8">expected exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)8">observed exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)9">expected exclusion contour smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)9">observed exclusion contour smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)10">expected exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)10">observed exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)11">expected exclusion contour right-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)11">observed exclusion contour right-handed smuon-pair production</a> </ul> <b>Cross section upper limits:</b> <ul> <li><a href="89413?version=1&table=xsecupperlimits1">upper limits on signal cross section for direct chargino-pair production via W decay</a> <li><a href="89413?version=1&table=xsecupperlimits2">upper limits on signal cross section for direct chargino-pair production via slepton decay</a> <li><a href="89413?version=1&table=xsecupperlimits3">upper limits on signal cross section for direct slepton-pair production</a> </ul> <b>Acceptances and Efficiencies for direct chargino-pair production via W decay grid </b> <ul> <li> <b>Acceptance</b> <br/> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[100,inf)forC1C1WWgrid">SR-DF-0J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[160,inf)forC1C1WWgrid">SR-DF-0J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[100,120)forC1C1WWgrid">SR-DF-0J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[120,160)forC1C1WWgrid">SR-DF-0J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[100,105)forC1C1WWgrid">SR-DF-0J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[105,110)forC1C1WWgrid">SR-DF-0J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[110,120)forC1C1WWgrid">SR-DF-0J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[120,140)forC1C1WWgrid">SR-DF-0J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[140,160)forC1C1WWgrid">SR-DF-0J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[160,180)forC1C1WWgrid">SR-DF-0J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[180,220)forC1C1WWgrid">SR-DF-0J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[220,260)forC1C1WWgrid">SR-DF-0J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[260,inf)forC1C1WWgrid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,inf)forC1C1WWgrid">SR-DF-1J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[160,inf)forC1C1WWgrid">SR-DF-1J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,120)forC1C1WWgrid">SR-DF-1J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[120,160)forC1C1WWgrid">SR-DF-1J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,105)forC1C1WWgrid">SR-DF-1J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[105,110)forC1C1WWgrid">SR-DF-1J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[110,120)forC1C1WWgrid">SR-DF-1J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[120,140)forC1C1WWgrid">SR-DF-1J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[140,160)forC1C1WWgrid">SR-DF-1J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[160,180)forC1C1WWgrid">SR-DF-1J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[180,220)forC1C1WWgrid">SR-DF-1J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[220,260)forC1C1WWgrid">SR-DF-1J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[260,inf)forC1C1WWgrid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,inf)forC1C1WWgrid">SR-SF-0J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[160,inf)forC1C1WWgrid">SR-SF-0J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,120)forC1C1WWgrid">SR-SF-0J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[120,160)forC1C1WWgrid">SR-SF-0J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,105)forC1C1WWgrid">SR-SF-0J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[105,110)forC1C1WWgrid">SR-SF-0J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[110,120)forC1C1WWgrid">SR-SF-0J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[120,140)forC1C1WWgrid">SR-SF-0J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[140,160)forC1C1WWgrid">SR-SF-0J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[160,180)forC1C1WWgrid">SR-SF-0J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[180,220)forC1C1WWgrid">SR-SF-0J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[220,260)forC1C1WWgrid">SR-SF-0J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[260,inf)forC1C1WWgrid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,inf)forC1C1WWgrid">SR-SF-1J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[160,inf)forC1C1WWgrid">SR-SF-1J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,120)forC1C1WWgrid">SR-SF-1J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[120,160)forC1C1WWgrid">SR-SF-1J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,105)forC1C1WWgrid">SR-SF-1J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[105,110)forC1C1WWgrid">SR-SF-1J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[110,120)forC1C1WWgrid">SR-SF-1J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[120,140)forC1C1WWgrid">SR-SF-1J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[140,160)forC1C1WWgrid">SR-SF-1J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[160,180)forC1C1WWgrid">SR-SF-1J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[180,220)forC1C1WWgrid">SR-SF-1J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[220,260)forC1C1WWgrid">SR-SF-1J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[260,inf)forC1C1WWgrid">SR-SF-1J-[260,inf) </a><br/> <li> <b>Efficiency</b> <br/> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,inf)forC1C1WWgrid">SR-DF-0J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[160,inf)forC1C1WWgrid">SR-DF-0J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,120)forC1C1WWgrid">SR-DF-0J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[120,160)forC1C1WWgrid">SR-DF-0J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,105)forC1C1WWgrid">SR-DF-0J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[105,110)forC1C1WWgrid">SR-DF-0J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[110,120)forC1C1WWgrid">SR-DF-0J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[120,140)forC1C1WWgrid">SR-DF-0J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[140,160)forC1C1WWgrid">SR-DF-0J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[160,180)forC1C1WWgrid">SR-DF-0J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[180,220)forC1C1WWgrid">SR-DF-0J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[220,260)forC1C1WWgrid">SR-DF-0J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[260,inf)forC1C1WWgrid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,inf)forC1C1WWgrid">SR-DF-1J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[160,inf)forC1C1WWgrid">SR-DF-1J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,120)forC1C1WWgrid">SR-DF-1J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[120,160)forC1C1WWgrid">SR-DF-1J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,105)forC1C1WWgrid">SR-DF-1J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[105,110)forC1C1WWgrid">SR-DF-1J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[110,120)forC1C1WWgrid">SR-DF-1J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[120,140)forC1C1WWgrid">SR-DF-1J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[140,160)forC1C1WWgrid">SR-DF-1J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[160,180)forC1C1WWgrid">SR-DF-1J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[180,220)forC1C1WWgrid">SR-DF-1J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[220,260)forC1C1WWgrid">SR-DF-1J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[260,inf)forC1C1WWgrid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,inf)forC1C1WWgrid">SR-SF-0J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[160,inf)forC1C1WWgrid">SR-SF-0J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,120)forC1C1WWgrid">SR-SF-0J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[120,160)forC1C1WWgrid">SR-SF-0J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,105)forC1C1WWgrid">SR-SF-0J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[105,110)forC1C1WWgrid">SR-SF-0J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[110,120)forC1C1WWgrid">SR-SF-0J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[120,140)forC1C1WWgrid">SR-SF-0J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[140,160)forC1C1WWgrid">SR-SF-0J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[160,180)forC1C1WWgrid">SR-SF-0J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[180,220)forC1C1WWgrid">SR-SF-0J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[220,260)forC1C1WWgrid">SR-SF-0J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[260,inf)forC1C1WWgrid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,inf)forC1C1WWgrid">SR-SF-1J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[160,inf)forC1C1WWgrid">SR-SF-1J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,120)forC1C1WWgrid">SR-SF-1J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[120,160)forC1C1WWgrid">SR-SF-1J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,105)forC1C1WWgrid">SR-SF-1J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[105,110)forC1C1WWgrid">SR-SF-1J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[110,120)forC1C1WWgrid">SR-SF-1J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[120,140)forC1C1WWgrid">SR-SF-1J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[140,160)forC1C1WWgrid">SR-SF-1J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[160,180)forC1C1WWgrid">SR-SF-1J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[180,220)forC1C1WWgrid">SR-SF-1J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[220,260)forC1C1WWgrid">SR-SF-1J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[260,inf)forC1C1WWgrid">SR-SF-1J-[260,inf) </a><br/> </ul> <b>Cutflow:</b> <ul> <li><a href="89413?version=1&table=Cutflow1">Cutflow for direct chargino-pair production via W decay $m(\tilde{\chi}^{\pm}_1,\tilde{\chi}^{0}_1)=(300,50) GeV$</a> <li><a href="89413?version=1&table=Cutflow1">Cutflow for direct chargino-pair production via slepton decay $m(\tilde{\chi}^{\pm}_1,\tilde{l},\tilde{\chi}^{0}_1)=(600,300,1) GeV$</a> <li><a href="89413?version=1&table=Cutflow1">Cutflow for direct slepton-pair production $m(\tilde{l},\tilde{\chi}^{0}_1)=(400,200) GeV$</a> </ul> <b>Truth Code snippets</b> are available under "Resources" (purple button on the left)

Observed events and predicted background yields from the fit for the CRs. For backgrounds whose normalisation is extracted from the fit, the yield expected from the simulation before the fit is also reported. The background denoted as "Other" in the Table includes the non-dominant background sources for this analysis, i.e. Z+jets, $t\bar t$ +V, Higgs and Drell-Yan events. A "–" symbol indicates that the background contribution is negligible.

Observed events and predicted post-fit background yields in the VRs. For backgrounds whose normalisation is extracted from the fit in the CRs, the yield expected from the simulation before the fit is also reported. The background denoted as "Other" includes the non-dominant background sources for this analysis, i.e. Z+jets, $t\bar t$ +V, Higgs and Drell-Yan events. A "–" symbol indicates that the background contribution is negligible.

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Measurement of elliptic flow of light nuclei at $\sqrt{s_{NN}}=$ 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV at the BNL Relativistic Heavy Ion Collider

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.C 94 (2016) 034908, 2016.
Inspire Record 1416992 DOI 10.17182/hepdata.104505

We present measurements of 2$^{nd}$ order azimuthal anisotropy ($v_{2}$) at mid-rapidity $(|y|<1.0)$ for light nuclei d, t, $^{3}$He (for $\sqrt{s_{NN}}$ = 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV) and anti-nuclei $\bar{\rm d}$ ($\sqrt{s_{NN}}$ = 200, 62.4, 39, 27, and 19.6 GeV) and $^{3}\bar{\rm He}$ ($\sqrt{s_{NN}}$ = 200 GeV) in the STAR (Solenoidal Tracker at RHIC) experiment. The $v_{2}$ for these light nuclei produced in heavy-ion collisions is compared with those for p and $\bar{\rm p}$. We observe mass ordering in nuclei $v_{2}(p_{T})$ at low transverse momenta ($p_{T}<2.0$ GeV/$c$). We also find a centrality dependence of $v_{2}$ for d and $\bar{\rm d}$. The magnitude of $v_{2}$ for t and $^{3}$He agree within statistical errors. Light-nuclei $v_{2}$ are compared with predictions from a blast wave model. Atomic mass number ($A$) scaling of light-nuclei $v_{2}(p_{T})$ seems to hold for $p_{T}/A < 1.5$ GeV/$c$. Results on light-nuclei $v_{2}$ from a transport-plus-coalescence model are consistent with the experimental measurements.

19 data tables

Mid-rapidity v2(pT) for d,anti-d,t,He,anti-He from minimum bias (0-80%) Au+Au collisions 200 GeV (d data points are also shown in Fig 5).

Mid-rapidity v2(pT) for d,anti-d,t,He from minimum bias (0-80%) Au+Au collisions 62.4 GeV.

Mid-rapidity v2(pT) for d,anti-d,t,He from minimum bias (0-80%) Au+Au collisions 39 GeV.

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Scaling properties at freeze-out in relativistic heavy ion collisions

The STAR collaboration Aggarwal, M.M. ; Ahammed, Z. ; Alakhverdyants, A.V. ; et al.
Phys.Rev.C 83 (2011) 034910, 2011.
Inspire Record 865572 DOI 10.17182/hepdata.104504

Identified charged pion, kaon, and proton spectra are used to explore the system size dependence of bulk freeze-out properties in Cu+Cu collisions at $\sqrt{s_{NN}}$=200 and 62.4 GeV. The data are studied with hydrodynamically-motivated Blast-wave and statistical model frameworks in order to characterize the freeze-out properties of the system. The dependence of freeze-out parameters on beam energy and collision centrality is discussed. Using the existing results from Au+Au and $pp$ collisions, the dependence of freeze-out parameters on the system size is also explored. This multi-dimensional systematic study furthers our understanding of the QCD phase diagram revealing the importance of the initial geometrical overlap of the colliding ions. The analysis of Cu+Cu collisions, which expands the system size dependence studies from Au+Au data with detailed measurements in the smaller system, shows that the bulk freeze-out properties of charged particles studied here scale with the total charged particle multiplicity at mid-rapidity, suggesting the relevance of initial state effects.

26 data tables

Negatively charged pion spectra from Cu+Cu collisions 200 GeV as a function of pT for different centralities.

Negatively charged pion spectra from Cu+Cu collisions 62.4 GeV as a function of pT for different centralities.

Negatively charged kaon spectra from Cu+Cu collisions 200 GeV as a function of pT for different centralities.

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Version 2
Search for resonances decaying into a weak vector boson and a Higgs boson in the fully hadronic final state produced in proton$-$proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Rev.D 102 (2020) 112008, 2020.
Inspire Record 1806507 DOI 10.17182/hepdata.94788

A search for heavy resonances decaying into a $W$ or $Z$ boson and a Higgs boson produced in proton$-$proton collisions at the Large Hadron Collider at $\sqrt{s} = 13$ TeV is presented. The analysis utilizes the dominant $W \to q \bar{q}^\prime$ or $Z \to q \bar{q}$ and $H \to b \bar{b}$ decays with substructure techniques applied to large-radius jets. A sample corresponding to an integrated luminosity of 139 fb$^{-1}$ collected with the ATLAS detector is analyzed and no significant excess of data is observed over the background prediction. The results are interpreted in the context of the Heavy Vector Triplet model with spin-1 $W^\prime$ and $Z^\prime$ bosons. Upper limits on the cross section are set for resonances with mass between 1.5 and 5.0 TeV, ranging from 6.8 to 0.53 fb for $W^\prime \to WH$ and from 8.7 to 0.53 fb for $Z^\prime \to ZH$ at the 95 % confidence level.

8 data tables

Observed and expected 95% CL upper limits on the cross section in the WH channel.

Observed and expected 95% CL upper limits on the cross section in the ZH channel.

Signal acceptance times efficiency of HVT WH(qqbb) events as a function of the resonance mass at different cut stages. Auxiliary table attached for 2 TeV mass point.

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Version 2
Search for dark matter in association with an energetic photon in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 02 (2021) 226, 2021.
Inspire Record 1829872 DOI 10.17182/hepdata.96846

A search for dark matter is conducted in final states containing a photon and missing transverse momentum in proton$-$proton collisions at $\sqrt{s}$ = 13 TeV. The data, collected during 2015$-$2018 by the ATLAS experiment at the CERN LHC, correspond to an integrated luminosity of 139 fb$^{-1}$. No deviations from the predictions of the Standard Model are observed and 95% confidence-level upper limits between 2.45 fb and 0.5 fb are set on the visible cross section for contributions from physics beyond the Standard Model, in different ranges of the missing transverse momentum. The results are interpreted as 95% confidence-level limits in models where weakly interacting dark-matter candidates are pair-produced via an s-channel axial-vector or vector mediator. Dark-matter candidates with masses up to 415 (580) GeV are excluded for axial-vector (vector) mediators, while the maximum excluded mass of the mediator is 1460 (1470) GeV. In addition, the results are expressed in terms of 95% confidence-level limits on the parameters of a model with an axion-like particle produced in association with a photon, and are used to constrain the coupling $g_{aZ\gamma}$ of an axion-like particle to the electroweak gauge bosons.

30 data tables

Distribution of $E^{miss}_T$ in data and for the expected SM background in the SRs after performing the 'simplified shape fit'. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The expectations for the simplified model for two different values of $m_{\chi}$ and $m_{med}$, and with $g_{q}=0.25$ and $g_{\chi}=1.0$ and for the ALP model are also shown. The lower panel shows the ratio of data to expected background event yields.

Distribution of $E^{miss}_T$ in data and for the expected SM background in the Single-Muon CR after performing the 'simplified shape fit'. The $E^{miss}_T$ calculation in this CR does not include the muon contribution. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The lower panel shows the ratio of data to expected background event yields.

Distribution of $E^{miss}_T$ in data and for the expected SM background in the Two-Muon CR after performing the 'simplified shape fit'. The $E^{miss}_T$ calculation in this CR does not include the muon contribution. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The lower panel shows the ratio of data to expected background event yields.

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Version 3
Searches for electroweak production of supersymmetric particles with compressed mass spectra in $\sqrt{s}=$ 13 TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Rev.D 101 (2020) 052005, 2020.
Inspire Record 1767649 DOI 10.17182/hepdata.91374

This paper presents results of searches for electroweak production of supersymmetric particles in models with compressed mass spectra. The searches use 139 fb$^{-1}$ of $\sqrt{s}=13$ TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider. Events with missing transverse momentum and two same-flavor, oppositely charged, low transverse momentum leptons are selected, and are further categorized by the presence of hadronic activity from initial-state radiation or a topology compatible with vector-boson fusion processes. The data are found to be consistent with predictions from the Standard Model. The results are interpreted using simplified models of $R$-parity-conserving supersymmetry in which the lightest supersymmetric partner is a neutralino with a mass similar to the lightest chargino, the second-to-lightest neutralino or the slepton. Lower limits on the masses of charginos in different simplified models range from 193 GeV to 240 GeV for moderate mass splittings, and extend down to mass splittings of 1.5 GeV to 2.4 GeV at the LEP chargino bounds (92.4 GeV). Similar lower limits on degenerate light-flavor sleptons extend up to masses of 251 GeV and down to mass splittings of 550 MeV. Constraints on vector-boson fusion production of electroweak SUSY states are also presented.

106 data tables

Expected 95% CL exclusion sensitivity for simplified models of direct higgsino production.

Observed 95% CL exclusion sensitivity for simplified models of direct higgsino production.

Expected 95% CL exclusion sensitivity for simplified models of direct wino-bino production, assuming $m(\tilde{\chi}_{2}^{0}) \times m(\tilde{\chi}_{1}^{0})<0$.

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Search for type-III seesaw heavy leptons in dilepton final states in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 218, 2021.
Inspire Record 1812090 DOI 10.17182/hepdata.95742

A search for the pair production of heavy leptons as predicted by the type-III seesaw mechanism is presented. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV, corresponding to 139 fb$^{-1}$ of integrated luminosity recorded by the ATLAS detector during Run 2 of the Large Hadron Collider. The analysis focuses on the final state with two light leptons (electrons or muons) of different flavour and charge combinations, with at least two jets and large missing transverse momentum. No significant excess over the Standard Model expectation is observed. The results are translated into exclusion limits on heavy-lepton masses, and the observed lower limit on the mass of the type-III seesaw heavy leptons is 790 GeV at 95% confidence level.

10 data tables

Cross-sections of the type-III seesaw process for mass points used in the analysis. Branching ratios into at least two leptons are presented with the corresponding effective cross-section.

Expected and observed 95 % CLs exclusion limits for the type-III seesaw process with the corresponding one- and two-standard-deviation bands, showing the 95 % CL upper limit on the cross-section.

Selection efficiencies in percentage relative to the events with at least two leptons for signal mass points used in the analysis. The efficiency is defined as the ratio of expected signal events in a signal region compared with the number of expected events produced, for integrated luminosity 139 fb$^{-1}$.

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Event by event < p(t) > fluctuations in Au - Au collisions at s(NN)**(1/2) = 130-GeV

The STAR collaboration Adams, J. ; Adler, C. ; Aggarwal, M.M. ; et al.
Phys.Rev.C 71 (2005) 064906, 2005.
Inspire Record 626905 DOI 10.17182/hepdata.102942

We present the first large-acceptance measurement of event-wise mean transverse momentum mean p_t fluctuations for Au-Au collisions at nucleon-nucleon center-of-momentum collision energy sqrt{s_{NN}} = 130 GeV. The observed non-statistical mean p_t fluctuations substantially exceed in magnitude fluctuations expected from the finite number of particles produced in a typical collision. The r.m.s. fractional width excess of the event-wise mean p_t distribution is 13.7 +/- 0.1(stat) +/- 1.3(syst)% relative to a statistical reference, for the 15% most-central collisions and for charged hadrons within pseudorapidity range |eta|<1, 2pi azimuth and 0.15 < p_t < 2 GeV/c. The width excess varies smoothly but non-monotonically with collision centrality, and does not display rapid changes with centrality which might indicate the presence of critical fluctuations. The reported mean p_t fluctuation excess is qualitatively larger than those observed at lower energies and differs markedly from theoretical expectations. Contributions to mean p_t mean fluctuations from semi-hard parton scattering in the initial state and dissipation in the bulk colored medium are discussed.

3 data tables

Event frequency distribution on $\sqrt{n}(\langle p_t\rangle - \hat{p}_t)/\sigma\hat{p}_t$ for 80% of primary charged hadrons in $|\eta|$ < 1 for 183k central events

Difference in upper panel between data and gamma reference

Centrality dependences of the measured charge independent (CI) and charge dependent (CD) difference factors $\Delta\sigma_{p_t:n}$ plus the corresponding values extrapolated to 100% tracking efficiency. Statistical errors $\pm$ 0.5 MeV/c; systematic errors are $\pm$ 9%. Difference factors extrapolated to 100% tracking efficiency and no secondary particle contamination. Uncertainties are $\pm$ 12%.


Azimuthal transverse single-spin asymmetries of inclusive jets and charged pions within jets from polarized-proton collisions at $\sqrt{s} = 500$ GeV

The STAR collaboration Adamczyk, Leszek ; Adams, Joseph ; Adkins, Kevin ; et al.
Phys.Rev.D 97 (2018) 032004, 2018.
Inspire Record 1618345 DOI 10.17182/hepdata.103056

We report the first measurements of transverse single-spin asymmetries for inclusive jet and jet + $\pi^{\pm}$ production at midrapidity from transversely polarized proton-proton collisions at $\sqrt{s} = 500$ GeV. The data were collected in 2011 with the STAR detector sampled from 23 pb$^{-1}$ integrated luminosity with an average beam polarization of 53%. Asymmetries are reported for jets with transverse momenta $6 < p_{T, jet} < 55$ GeV/c and pseudorapidity $|\eta| < 1$. Presented are measurements of the inclusive-jet azimuthal transverse single-spin asymmetry, sensitive to twist-3 initial-state quark-gluon correlators; the Collins asymmetry, sensitive to quark transversity coupled to the polarized Collins fragmentation function; and the first measurement of the "Collins-like" asymmetry, sensitive to linearly polarized gluons. Within the present statistical precision, inclusive-jet and Collins-like asymmetries are small, with the latter allowing the first experimental constraints on gluon linear polarization in a polarized proton. At higher values of jet transverse momenta, we observe the first non-zero Collins asymmetries in polarized-proton collisions, with a statistical significance of greater than $5\sigma$. The results span a range of x similar to results from SIDIS but at much higher $Q^{2}$. The Collins results enable tests of universality and factorization-breaking in the transverse momentum-dependent formulation of perturbative quantum chromodynamics.

20 data tables

Inclusive jet asymmetries $A_{UT}^{\sin(\theta_S)}$ as a function of particle-jet $p_T$.

Inclusive jet asymmetries $A_{UT}^{\sin(\theta_S)}$ as a function of particle-jet $p_T$.

Collins-like asymmetries as a function of particle-jet $p_T$.

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Longitudinal Double-Spin Asymmetries for $\pi^{0}$s in the Forward Direction for 510 GeV Polarized $pp$ Collisions

The STAR collaboration Adam, Jaroslav ; Adamczyk, Leszek ; Adams, Joseph ; et al.
Phys.Rev.D 98 (2018) 032013, 2018.
Inspire Record 1674826 DOI 10.17182/hepdata.103058

The STAR Collaboration reports measurements of the longitudinal double-spin asymmetry, $A_{LL}$, for neutral pions produced at forward directions in polarized proton-proton collisions, at a center-of-mass energy of $510$ GeV. Results are given for transverse momenta in the range $2

2 data tables

Longitudinal Double-Spin Asymmetry, $A_{LL}$ vs $\pi^0$ transverse momentum in polarized pp collisions at $\sqrt{s}$ = 510 GeV. $\pm 6.7\%$ polarization scale uncertainty not shown.

Longitudinal Double-Spin Asymmetry, $A_{LL}$ vs $\pi^0$ transverse momentum in polarized pp collisions at $\sqrt{s}$ = 510 GeV. $\pm 6.7\%$ polarization scale uncertainty not shown.


Azimuthal anisotropy in Cu$+$Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV

The STAR collaboration Adamczyk, Leszek ; Adams, Joseph ; Adkins, Kevin ; et al.
Phys.Rev.C 98 (2018) 014915, 2018.
Inspire Record 1641113 DOI 10.17182/hepdata.103057

The azimuthal anisotropic flow of identified and unidentified charged particles has been systematically studied in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV for harmonics $n=$ 1-4 in the pseudorapidity range $|\eta|<1$. The directed flow in Cu+Au collisions is compared with the rapidity-odd and, for the first time, the rapidity-even components of charged particle directed flow in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200~GeV. The slope of the directed flow pseudorapidity dependence in Cu+Au collisions is found to be similar to that in Au+Au collisions, with the intercept shifted toward positive $\eta$ values, i.e., the Cu-going direction. The mean transverse momentum projected onto the spectator plane, $\langle p_x\rangle$, in Cu+Au collision also exhibits approximately linear dependence on $\eta$ with the intercept at about $\eta\approx-0.4$, closer to the rapidity of the Cu+Au system center-of-mass. The observed dependencies find natural explanation in a picture of the directed flow originating partly due the "tilted source" and partly due to the rapidity dependent asymmetry in the initial density distribution. Charge-dependence of the $\langle p_x\rangle$ was also observed in Cu+Au collisions, indicating an effect of the initial electric field created by charge difference of the spectator protons in two colliding nuclei. The rapidity-even component of directed flow in Au+Au collisions is close to that in Pb+Pb collisions at $\sqrt{s_{_{NN}}}$ = 2.76 TeV, indicating a similar magnitude of dipole-like fluctuations in the initial-state density distribution. Higher harmonic flow in Cu+Au collisions exhibits similar trends to those observed in Au+Au and Pb+Pb collisions and is qualitatively reproduced by a viscous hydrodynamic model and a multi-phase transport model. For all harmonics with $n\ge2$ we observe an approximate scaling of $v_n$ with the number of constituent quarks.

33 data tables

Directed flow $v_1(\eta)$ and $<p_x>(\eta)$ of charged particles measured with respect to the target and projectile spectator planes in 10%-40% centrality for Cu+Au collisions.

Directed flow $v_1(\eta)$ and $<p_x>(\eta)$ of charged particles measured with respect to the target and projectile spectator planes in 10%-40% centrality for Au+Au collisions.

Conventional and fluctuation components of directed flow $v_1(\eta)$ and momentum shift $<p_x>/<p_T>(\eta)$ of charged particles in 10%-40% centrality for Cu+Au and Au+Au collisions.

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Neutral pion cross section and spin asymmetries at intermediate pseudorapidity in polarized proton collisions at $\sqrt{s} = 200$ GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.D 89 (2014) 012001, 2014.
Inspire Record 1253360 DOI 10.17182/hepdata.103061

The differential cross section and spin asymmetries for neutral pions produced within the intermediate pseudorapidity range 0.8 < {\eta} < 2.0 in polarized proton-proton collisions at sqrt{s} = 200 GeV are presented. Neutral pions were detected using the endcap electromagnetic calorimeter in the STAR detector at RHIC. The cross section was measured over a transverse momentum range of 5 < p_T < 16 GeV/c and is found to be within the scale uncertainty of a next-to-leading order perturbative QCD calculation. The longitudinal double-spin asymmetry, A_LL, is measured in the same pseudorapidity range. This quantity is sensitive to the gluonic contribution to the proton spin, {\Delta}g(x), at low Bjorken-x (down to x approx 0.01), where it is less constrained by measurements at central pseudorapidity. The measured A_LL is consistent with model predictions. The parity-violating asymmetry, A_L, is also measured and found to be consistent with zero. The transverse single-spin asymmetry, A_N, is measured within a previously unexplored kinematic range in Feynman-x and p_T. Such measurements may aid our understanding of the on-set and kinematic dependence of the large asymmetries observed at more forward pseudorapidity ({\eta} approx 3) and their underlying mechanisms. The A_N results presented are consistent with a twist-3 model prediction of a small asymmetry within the present kinematic range.

16 data tables

Distributions of x1 and x2 in two different bins of reconstructed $\pi^{0}$ pT for events at $\sqrt{s}$ = 200 GeV over 0.8 < $\eta$ < 2.

Comparison of data to Monte Carlo for the distributions of two-photon invariant mass (left) and energy for the higher (center) and lower (right) energy photon.

Comparison of data to Monte Carlo for the distributions of two-photon invariant mass (left) and energy for the higher (center) and lower (right) energy photon.

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Experimental studies of di-jets in Au + Au collisions using angular correlations with respect to back-to-back leading hadrons

The STAR collaboration Adamczyk, L. ; Agakishiev, G. ; Aggarwal, M.M. ; et al.
Phys.Rev.C 87 (2013) 044903, 2013.
Inspire Record 1206352 DOI 10.17182/hepdata.103059

Jet-medium interactions are studied via a multi-hadron correlation technique (called "2+1"), where a pair of back-to-back hadron triggers with large transverse momentum is used as a proxy for a di-jet. This work extends the previous analysis for nearly-symmetric trigger pairs with the highest momentum threshold of trigger hadron of 5 GeV/$c$ with the new calorimeter-based triggers with energy thresholds of up to 10 GeV and above. The distributions of associated hadrons are studied in terms of correlation shapes and per-trigger yields on each trigger side. In contrast with di-hadron correlation results with single triggers, the associated hadron distributions for back-to-back triggers from central Au+Au data at $\sqrt{s_{NN}}$=200 GeV show no strong modifications compared to d+Au data at the same energy. An imbalance in the total transverse momentum between hadrons attributed to the near-side and away-side of jet-like peaks is observed. The relative imbalance in the Au+Au measurement with respect to d+Au reference is found to increase with the asymmetry of the trigger pair, consistent with expectation from medium-induced energy loss effects. In addition, this relative total transverse momentum imbalance is found to decrease for softer associated hadrons. Such evolution indicates the energy missing at higher associated momenta is converted into softer hadrons.

8 data tables

Projections of 2-D correlation functions on $\Delta \phi$ (a) (with $|\Delta \eta|$ < 1.0) and $\Delta \eta$ (b) (with $|\Delta \phi|$ < 0.7) for the hadrons associated with their respective triggers (T1 for near-side, T2 for away–side) are shown for d+Au (circles) and central 0-20% Au+Au (squares).

Projections of 2-D correlation functions on $\Delta \phi$ (a) (with $|\Delta \eta|$ < 1.0) and $\Delta \eta$ (b) (with $|\Delta \phi|$ < 0.7) for the hadrons associated with their respective triggers (T1 for near-side, T2 for away–side) are shown for d+Au (circles) and central 0-20% Au+Au (squares).

Projections of 2-D correlation functions on $\Delta \phi$ (a) (with $|\Delta \eta|$ < 1.0) and $\Delta \eta$ (b) (with $|\Delta \phi|$ < 0.7) for the hadrons associated with their respective triggers (T1 for near-side, T2 for away–side) are shown for d+Au (circles) and central 0-20% Au+Au (squares).

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System-size dependence of transverse momentum correlations at $\sqrt{s_{NN}}=62.4$ and 200 GeV at the BNL Relativistic Heavy Ion Collider

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.C 87 (2013) 064902, 2013.
Inspire Record 1216565 DOI 10.17182/hepdata.103060

We present a study of the average transverse momentum ($p_t$) fluctuations and $p_t$ correlations for charged particles produced in Cu+Cu collisions at midrapidity for $\sqrt{s_{NN}} =$ 62.4 and 200 GeV. These results are compared with those published for Au+Au collisions at the same energies, to explore the system size dependence. In addition to the collision energy and system size dependence, the $p_t$ correlation results have been studied as functions of the collision centralities, the ranges in $p_t$, the pseudorapidity $\eta$, and the azimuthal angle $\phi$. The square root of the measured $p_t$ correlations when scaled by mean $p_t$ is found to be independent of both colliding beam energy and system size studied. Transport-based model calculations are found to have a better quantitative agreement with the measurements compared to models which incorporate only jetlike correlations.

17 data tables

Event-by-event $\langle p_{t}\rangle$ distributions for data and mixed events in central Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 and 62.4 GeV.

Comparison of dynamical $\langle p_{t}\rangle$ fluctuations in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV as a function of the number of participanting nucleons.

Comparison of dynamical $\langle p_{t}\rangle$ fluctuations in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV as a function of the number of participanting nucleons.

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Strangelet search at RHIC

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 76 (2007) 011901, 2007.
Inspire Record 698939 DOI 10.17182/hepdata.104503

We have searched for strangelets in a triggered sample of 61 million central (top 4%) Au+Au collisions at $\sNN = 200 $GeV near beam rapidities at the STAR detector. We have sensitivity to metastable strangelets with lifetimes of order $\geq 0.1 ns$, in contrast to limits over ten times longer in AGS studies and longer still at the SPS. Upper limits of a few 10^{-6} to 10^{-7} per central Au+Au collision are set for strangelets with mass ${}^{>}_{\sim}30$ GeV/c^{2}.

2 data tables

Upper limit for neutral (Z=0) and charged (Z=5) strangelet as a function of mass.

Upper limit for charged (Z=1) strangelet as a function of lifetime.


Version 2
Longitudinal Spin Transfer to Lambda and anti-Lambda Hyperons in Polarized Proton-Proton Collisions at s**(1/2) = 200-GeV

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.D 80 (2009) 111102, 2009.
Inspire Record 833423 DOI 10.17182/hepdata.99048

The longitudinal spin transfer, $D_{LL}$, from high energy polarized protons to $\Lambda$ and $\bar{\Lambda}$ hyperons has been measured for the first time in proton-proton collisions at $\sqrt{s} = 200 \mathrm{GeV}$ with the STAR detector at RHIC. The measurements cover pseudorapidity, $\eta$, in the range $|\eta| < 1.2$ and transverse momenta, $p_\mathrm{T}$, up to $4 \mathrm{GeV}/c$. The longitudinal spin transfer is found to be $D_{LL}= -0.03\pm 0.13(\mathrm{stat}) \pm 0.04(\mathrm{syst})$ for inclusive $\Lambda$ and $D_{LL} = -0.12 \pm 0.08(\mathrm{stat}) \pm 0.03(\mathrm{syst})$ for inclusive $\bar{\Lambda}$ hyperons with $<\eta> = 0.5$ and $<p_\mathrm{T}> = 3.7 \mathrm{GeV}/c$. The dependence on $\eta$ and $p_\mathrm{T}$ is presented.

7 data tables

The spin transfer $D_{LL}$ to (a) $\Lambda$ and (b) $\bar{\Lambda}$ hyperons produced at positive pseudorapidity with respect to the polarized proton beam from $MB$, $JP$, and $HT$ data versus hyperon transverse momenta $p_{T}$. The sizes of the statistical and systematic uncertainties are indicated by the vertical bars and bands, respectively. For clarity, the HT data points have been shifted slightly in $p_{T}$. The dotted vertical lines indicate the $p_{T}$ intervals in the analysis of HT and JP data.

The spin transfer $D_{LL}$ to (a) $\Lambda$ and (b) $\bar{\Lambda}$ hyperons produced at positive pseudorapidity with respect to the polarized proton beam from $MB$, $JP$, and $HT$ data versus hyperon transverse momenta $p_{T}$. The sizes of the statistical and systematic uncertainties are indicated by the vertical bars and bands, respectively. For clarity, the HT data points have been shifted slightly in $p_{T}$. The dotted vertical lines indicate the $p_{T}$ intervals in the analysis of HT and JP data.

Comparison of $\Lambda$ and $\bar{\Lambda}$ spin transfer $D_{LL}$ in polarized proton-proton collisions at $\sqrt{s} = 200 GeV$ for (a) positive and (b) negative $\eta$ versus $p_{T}$. The vertical bars and bands indicate the sizes of the statistical and systematic uncertainties, respectively. The $\bar{\Lambda}$ data points have been shifted slightly in $p_{T}$ for clarity. The dotted vertical lines indicate the $p_{T}$ intervals in the analysis of HT and JP data. The horizontal lines show model predictions evaluated at $\eta$ and largest $p_{T}$ of the data.

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Version 4
Search for the $HH \rightarrow b \bar{b} b \bar{b}$ process via vector-boson fusion production using proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 07 (2020) 108, 2020.
Inspire Record 1775750 DOI 10.17182/hepdata.91237

A search for Higgs boson pair production via vector-boson fusion (VBF) in the $b\bar{b}b\bar{b}$ final state is carried out with the ATLAS experiment using 126 fb$^{-1}$ of proton-proton collision data delivered at $\sqrt{s} = 13$ TeV by the Large Hadron Collider. This search is sensitive to VBF production of additional heavy bosons that may decay into Higgs boson pairs, and in a non-resonant topology it can constrain the quartic coupling between the Higgs bosons and vector bosons. No significant excess relative to the Standard Model expectation is observed, and limits on the production cross-section are set at the 95 % confidence level for a heavy scalar resonance in the context of an extended Higgs sector, and for non-resonant Higgs boson pair production. Interpretation in terms of the coupling between a Higgs boson pair and two vector bosons is also provided: coupling values normalised to the Standard Model expectation of $\kappa_{2V} < -0.43$ and $\kappa_{2V} > 2.56$ are excluded at the 95 % confidence level in data.

6 data tables

Acceptance x efficiency versus $\kappa_{2V}$ for non-resonant signal of $HH$.

Acceptance x efficiency versus resonance mass for both narrow and broad resonance $X$ to $HH$.

Post-fit mass distribution of the $HH$ candidates in the signal region. The expected background is shown after the profile-likelihood fit to data with the background-only hypothesis; the narrow-width resonant signal at 800 GeV and the non-resonant signal at $\kappa_{2V}$ = 3 are overlaid, both normalised to the corresponding observed upper limits on the cross-section.

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Pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d + Au collisions at S(NN)**(1/2) = 200-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 70 (2004) 064907, 2004.
Inspire Record 656934 DOI 10.17182/hepdata.102944

The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at $\sqrt{s_{NN}}=200$ GeV are presented. The charged particle density at mid-rapidity, its pseudorapidity asymmetry and centrality dependence are reasonably reproduced by a Multi-Phase Transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for \pT below 5 GeV/$c$. The ratio of central to peripheral spectra in d+Au collisions shows enhancement at 2 $<$ \pT $<$ 6 GeV/$c$, with a larger effect at backward rapidity than forward rapidity. Our measurements are in qualitative agreement with gluon saturation and in contrast to calculations based on incoherent multiple partonic scatterings.

5 data tables

The p$_T$ spectra of charged hadrons for various centrality classes.

The pseudorapidity dependence of charged particle densities for various centrality classes.

The ratio of charged hadron spectra in the backward rapidity to forward rapidity region for minimum bias and ZDC-d neutron-tagged events.

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Multi-strange baryon elliptic flow in Au + Au collisions at s(NN)**(1/2) = 200-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.Lett. 95 (2005) 122301, 2005.
Inspire Record 681161 DOI 10.17182/hepdata.102945

We report on the first measurement of elliptic flow $v_2(p_T)$ of multi-strange baryons $\Xi+\bar{Xi}$ and $\Omega+\bar{Omega} in heavy-ion collisions. In minimum bias Au+Au collisions at sqrt(s_NN) = 200 GeV, a significant amount of elliptic flow, comparable to other non-strange baryons, is observed for multi-strange baryons which are expected to be particularly sensitive to the dynamics of the partonic stage of heavy-ion collisions. The $p_T$ dependence of $v_2$ of the multi-strange baryons confirms the number of constituent quark scaling previously observed for lighter hadrons. These results support the idea that a substantial fraction of the observed collective motion is developed at the early partonic stage in ultra-relativistic nuclear collisions at RHIC.

5 data tables

$\Xi^{-} + \Xi^{+}$ invariant mass distribution from minimum bias (0–80%) Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

$\Omega^{-} + \Omega^{+}$ invariant mass distribution from minimum bias (0–80%) Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Azimuthal distributions with respect to the event plane of the $\Xi^{-} + \Xi^{+}$ and $\Omega^{-} + \Omega^{+}$ raw yields.

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Directed flow in Au+Au collisions at s(NN)**(1/2) = 62-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 73 (2006) 034903, 2006.
Inspire Record 695404 DOI 10.17182/hepdata.102947

We present the directed flow ($v_1$) measured in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 62.4 GeV in the mid-pseudorapidity region $|\eta|<1.3$ and in the forward pseudorapidity region $2.5 < |\eta| < 4.0$. The results are obtained using the three-particle cumulant method, the event plane method with mixed harmonics, and for the first time at the Relativistic Heavy Ion Collider (RHIC), the standard method with the event plane reconstructed from spectator neutrons. Results from all three methods are in good agreement. Over the pseudorapidity range studied, charged particle directed flow is in the direction opposite to that of fragmentation neutrons.

19 data tables

Directed flow of charged particles as a function of pseudorapidity, for centrality 10%-70%.

Directed flow of charged particles as a function of pseudorapidity, for centrality 10%-70%.

Directed flow of charged particles as a function of pseudorapidity, for centrality 10%-70%.