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Version 2
Multiplicity Dependence of Pion, Kaon, Proton and Lambda Production in p-Pb Collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B728 (2014) 25-38, 2014.
Inspire Record 1244523 DOI 10.17182/hepdata.61786

In this Letter, comprehensive results on ${\rm\pi}^\pm$, K$^\pm$, K$^0_S$, p, $\rm\bar{p}$, $\rm \Lambda$ and $\rm \bar{\Lambda}$ production at mid-rapidity ($0 < y_{\rm cms} < 0.5$) in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV, measured by the ALICE detector at the LHC, are reported. The transverse momentum distributions exhibit a hardening as a function of event multiplicity, which is stronger for heavier particles. This behavior is similar to what has been observed in pp and Pb-Pb collisions at the LHC. The measured $p_{\rm T}$ distributions are compared to results at lower energy and with predictions based on QCD-inspired and hydrodynamic models.

27 data tables

pT-differential invariant yield of charged pions in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

pT-differential invariant yield of charged pions in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

pT-differential invariant yield of charged kaons in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

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Longitudinal and azimuthal evolution of two-particle transverse momentum correlations in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Lett. B804 (2020) 135375, 2020.
Inspire Record 1762340 DOI 10.17182/hepdata.93887

This paper presents the first measurements of the charge independent (CI) and charge dependent (CD) two-particle transverse momentum correlators $G_{2}^{\rm CI}$ and $G_{2}^{\rm CD}$ in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV by the ALICE collaboration. The correlators are measured as a function of pair separation in pseudorapidity ($\Delta \eta$) and azimuth ($\Delta \varphi$) and as a function of collision centrality. The correlator $G_{2}^{\rm CI}$ exhibits a longitudinal broadening while undergoing a monotonic azimuthal narrowing from peripheral to central collisions. By contrast, $G_{2}^{\rm CD}$ exhibits a narrowing along both dimensions towards central events. These features are not reproduced by models such as HIJING and AMPT. However, the observed narrowing of the correlators is expected to result from the stronger transverse flow profiles produced in more central collisions and the longitudinal broadening is predicted to be sensitive to momentum currents and the shear viscosity per unit of entropy density $\eta/s$ of the matter produced in the collisions. The observed broadening is found to be consistent with the hypothesized lower bound of $\eta/s$ and is in qualitative agreement with values obtained from anisotropic flow measurements.

12 data tables

Longitudinal width evolution with the number of participants of the two-particle transverse momentum correlation $G_{2}^{\rm CI}$ in Pb--Pb collisions at $\sqrt{s_{\rm NN}}=2.76\;\text{TeV}$. The widths are extracted from bi-dimensional (2D) or projection (1D) fits of the correlation function.

Two-particle transverse momentum correlation $G_{2}^{\rm CI}$ for central (0-5%) Pb--Pb collisions at $\sqrt{s_{\rm NN}}=2.76\;\text{TeV}$.

Two-particle transverse momentum correlation $G_{2}^{\rm CI}$ for semi-central (30-40%) Pb--Pb collisions at $\sqrt{s_{\rm NN}}=2.76\;\text{TeV}$.

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Search for the electroweak diboson production in association with a high-mass dijet system in semileptonic 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.
Phys.Rev. D100 (2019) 032007, 2019.
Inspire Record 1735560 DOI 10.17182/hepdata.89647

This paper reports on a search for electroweak diboson (WW/WZ/ZZ) production in association with a high-mass dijet system, using data from proton-proton collisions at a center-of-mass energy of s=13  TeV. The data, corresponding to an integrated luminosity of 35.5  fb-1, were recorded with the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The search is performed in final states in which one boson decays leptonically, and the other boson decays hadronically. The hadronically decaying W/Z boson is reconstructed as either two small-radius jets or one large-radius jet using jet substructure techniques. The electroweak production of WW/WZ/ZZ in association with two jets is measured with an observed (expected) significance of 2.7 (2.5) standard deviations, and the fiducial cross section is measured to be 45.1±8.6(stat.)-14.6+15.9(syst.)  fb.

2 data tables

Summary of predicted and measured fiducial cross sections for EW $VVjj$ production. The three lepton channels are combined. For the measured fiducial cross sections in the merged and resolved categories, two signal-strength parameters are used in the combined fit, one for the merged category and the other one for the resolved category; while for the measured fiducial cross section in the inclusive fiducial phase space, a single signal-strength parameter is used. For the SM predicted cross section, the error is the theoretical uncertainty (theo.). For the measured cross section, the first error is the statistical uncertainty (stat.), and the second error is the systematic uncertainty (syst.).

Summary of predicted and measured fiducial cross sections for EW $VVjj$ production. in the three lepton channels. The measured values are obtained from a simultaneous fit where each lepton channel has its own signal-strength parameter, and in each lepton channel the same signal-strength parameter is applied to both the merged and resolved categories. For the SM predicted cross section, the error is the theoretical uncertainty (theo.). For the measured cross section, the first error is the statistical uncertainty (stat.), and the second error is the systematic uncertainty (syst.).


Version 2
Measurement of the Drell-Yan triple-differential cross section in $pp$ collisions at $\sqrt{s} = 8$ TeV

The ATLAS collaboration Aaboud, M. ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 1712 (2017) 059, 2017.
Inspire Record 1630886 DOI 10.17182/hepdata.77492

This paper presents a measurement of the triple-differential cross section for the Drell-Yan process Z/γ$^{*}$ → ℓ$^{+}$ ℓ$^{−}$ where ℓ is an electron or a muon. The measurement is performed for invariant masses of the lepton pairs, m$_{ℓℓ}$ , between 46 and 200 GeV using a sample of 20.2 fb$^{−1}$ of pp collisions data at a centre-of-mass energy of $ \sqrt{s}=8 $ TeV collected by the ATLAS detector at the LHC in 2012. The data are presented in bins of invariant mass, absolute dilepton rapidity, |y$_{ℓℓ}$|, and the angular variable cos θ$^{*}$ between the outgoing lepton and the incoming quark in the Collins-Soper frame. The measurements are performed in the range |y$_{ℓℓ}$ | < 2.4 in the muon channel, and extended to |y$_{ℓℓ}$ | < 3.6 in the electron channel. The cross sections are used to determine the Z boson forward-backward asymmetry as a function of |y$_{ℓℓ}$ | and m$_{ℓℓ}$ . The measurements achieve high-precision, below the percent level in the pole region, excluding the uncertainty in the integrated luminosity, and are in agreement with predictions. These precision data are sensitive to the parton distribution functions and the effective weak mixing angle.

6 data tables

Detailed breakdown of systematic uncertainties for the measurement in the central rapidity muon channel. Common systematic uncertainty on the luminosity measurment of 1.8% is not included. Correlated systematic uncertainties with the suffix :A should be treated as additive and with the suffix :M should be treated as multiplicative. The source 'sys,uncor' represents bin-to-bin uncorrelated systematic uncertainty. The cross sections are given at the Born QED level. 'C Dressed' represents the multiplicative correction factor to translate the cross sections to the dressed level with the cone radius of 0.1: SigmaDressed = C Dressed * SigmaBorn.

Detailed breakdown of systematic uncertainties for the measurement in the central rapidity electron channel. Common systematic uncertainty on the luminosity measurment of 1.8% is not included. Correlated systematic uncertainties with the suffix :A should be treated as additive and with the suffix :M should be treated as multiplicative. The source 'sys,uncor' represents bin-to-bin uncorrelated systematic uncertainty. The cross sections are given at the Born QED level. 'C Dressed' represents the multiplicative correction factor to translate the cross sections to the dressed level with the cone radius of 0.1: SigmaDressed = C Dressed * SigmaBorn.

Detailed breakdown of systematic uncertainties for the measurement in the forward rapidity electron channel. Common systematic uncertainty on the luminosity measurment of 1.8% is not included. Correlated systematic uncertainties with the suffix :A should be treated as additive and with the suffix :M should be treated as multiplicative. The source 'sys,uncor' represents bin-to-bin uncorrelated systematic uncertainty. The cross sections are given at the Born QED level. 'C Dressed' represents the multiplicative correction factor to translate the cross sections to the dressed level with the cone radius of 0.1: SigmaDressed = C Dressed * SigmaBorn.

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Measurement of the inclusive isolated-photon cross section in $pp$ collisions at $\sqrt{s}=13$ TeV using 36 fb$^{-1}$ of ATLAS data

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 1910 (2019) 203, 2019.
Inspire Record 1748270 DOI 10.17182/hepdata.91968

The differential cross section for isolated-photon production in $pp$ collisions is measured at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC using an integrated luminosity of 36.1 fb$^{-1}$. The differential cross section is presented as a function of the photon transverse energy in different regions of photon pseudorapidity. The differential cross section as a function of the absolute value of the photon pseudorapidity is also presented in different regions of photon transverse energy. Next-to-leading-order QCD calculations from JETPHOX and SHERPA as well as next-to-next-to-leading-order QCD calculations from NNLOJET are compared with the measurement, using several parameterisations of the proton parton distribution functions. The predictions provide a good description of the data within the experimental and theoretical uncertainties.

8 data tables

Measured cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $|\eta^{\gamma}|<0.6$.

Measured cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $0.6<|\eta^{\gamma}|<1.37$.

Measured cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $1.56<|\eta^{\gamma}|<1.81$.

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Scattering studies with low-energy kaon-proton femtoscopy in proton-proton collisions at the LHC

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Phys.Rev.Lett. 124 (2020) 092301, 2020.
Inspire Record 1737592 DOI 10.17182/hepdata.93732

The study of the strength and behavior of the antikaon-nucleon (K¯N) interaction constitutes one of the key focuses of the strangeness sector in low-energy quantum chromodynamics (QCD). In this Letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K+p⊕K−p¯) and (K-p⊕K+p¯) pairs measured in pp collisions at s=5, 7, and 13 TeV are reported. A structure observed around a relative momentum of 58  MeV/c in the measured correlation function of (K-p⊕K+p¯) with a significance of 4.4σ constitutes the first experimental evidence for the opening of the (K¯0n⊕K0n¯) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to Jülich and Kyoto models in addition to the Coulomb potential. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K¯N threshold for low-energy QCD chiral models.

7 data tables

K-p correlation function in p-p collisions at $\sqrt{s}=5$ TeV.

K-p correlation function in p-p collisions at $\sqrt{s}=7$ TeV.

K-p correlation function in p-p collisions at $\sqrt{s}=13$ TeV.

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Studies of J/$\psi$ production at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
JHEP 2002 (2020) 041, 2020.
Inspire Record 1753083 DOI 10.17182/hepdata.93341

The inclusive J/ψ production in Pb–Pb collisions at the center-of-mass energy per nucleon pair $ \sqrt{s_{\mathrm{NN}}} $ = 5.02 TeV, measured with the ALICE detector at the CERN LHC, is reported. The J/ψ meson is reconstructed via the dimuon decay channel at forward rapidity (2.5 < y < 4) down to zero transverse momentum. The suppression of the J/ψ yield in Pb–Pb collisions with respect to binary-scaled pp collisions is quantified by the nuclear modification factor (R$_{AA}$). The R$_{AA}$ at $ \sqrt{s_{\mathrm{NN}}} $ = 5.02 TeV is presented and compared with previous measurements at $ \sqrt{s_{\mathrm{NN}}} $ = 2.76 TeV as a function of the centrality of the collision, and of the J/ψ transverse momentum and rapidity. The inclusive J/ψ RAA shows a suppression increasing toward higher transverse momentum, with a steeper dependence for central collisions. The modification of the J/ψ average transverse momentum and average squared transverse momentum is also studied. Comparisons with the results of models based on a transport equation and on statistical hadronization are carried out.[graphic not available: see fulltext]

43 data tables

Transverse momentum dependence (in 0-90% centrality class) of the inclusive J/$\psi$ $R_{\rm AA}$. The first uncertainty is statistical, the second is the uncorrelated systematic, while the third one is a $p_{\rm T}$-correlated systematic uncertainty.

The minimum and maximum variations for the $R_{\rm AA}$ of prompt J/$\psi$ with respect to the $R_{\rm AA}$ values of inclusive J/$\psi$ reported in Table 1. The variations correspond to two extreme hypotheses on the unknown contribution of non-prompt J/$\psi$.

Transverse momentum dependence (in 0-90% centrality class) of the ratio of the inclusive J/$\psi$ $R_{\rm AA}$ at $\sqrt{s_{NN}}$= 5.02 and 2.76 TeV. The first uncertainty is statistical, the second is the uncorrelated systematic, while the third one is a $p_{\rm T}$-correlated systematic uncertainty.

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Measurement of associated Z + charm production in proton-proton collisions at $\sqrt{s} = $ 8 TeV

The CMS collaboration Sirunyan, A.M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J. C78 (2018) 287, 2018.
Inspire Record 1634835 DOI 10.17182/hepdata.85868

A study of the associated production of a $\mathrm{Z} $ boson and a charm quark jet ( $\mathrm{Z} + \mathrm{c} $ ), and a comparison to production with a $\mathrm{b} $ quark jet ( $\mathrm{Z} + \mathrm{b} $ ), in $\mathrm {p}\mathrm {p}$ collisions at a centre-of-mass energy of 8 $\,\text {TeV}$ are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 $\,\text {fb}^{-1}$ , collected with the CMS detector at the CERN LHC. The $\mathrm{Z} $ boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of $\mathrm{c} $ or $\mathrm{b} $ flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with $p_{\mathrm {T}} ^{\ell } > 20\,\text {GeV} $ , ${|\eta ^{\ell }|} < 2.1$ , $71< m_{\ell \ell } < 111\,\text {GeV} $ , and heavy flavour jets with $p_{\mathrm {T}} ^{\text {jet}} > 25\,\text {GeV} $ and ${|\eta ^{ \text {jet}}|} < 2.5$ . The $\mathrm{Z} + \mathrm{c} $ production cross section is measured to be $\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{c} + X) \mathcal {B}(\mathrm{Z} \rightarrow \ell ^+\ell ^-) = 8.8 \pm 0.5\,\text {(stat)} \pm 0.6\,\text {(syst)} \,\text {pb} $ . The ratio of the $\mathrm{Z} + \mathrm{c} $ and $\mathrm{Z} + \mathrm{b} $ production cross sections is measured to be $\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{c} + X)/\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{b} + X) = 2.0 \pm 0.2\,\text {(stat)} \pm 0.2\,\text {(syst)} $ . The $\mathrm{Z} + \mathrm{c} $ production cross section and the cross section ratio are also measured as a function of the transverse momentum of the $\mathrm{Z} $ boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.

28 data tables

Signal yields N(Z+c) and N(Z+b), efficiency*acceptance correction factors C(Z+c) and C(Z+b), cross section sigma(Z+c)B and cross section ratios sigma(Z+c)/sigma(Z+b) in the three categories (semileptonic, D+-, D*) and in the two Z boson decay channels (e+e-, mu+mu-). The factors that correct the acceptance and selection inefficiencies are also given. They include the relevant branching fraction for the corresponding channel. All uncertainties quoted in the table are statistical, except for those of the measured cross sections and cross section ratios where the first uncertainty is statistical and the second is the estimated systematic uncertainty

Transverse momentum distribution of the selected muon-inside-a-jet for events with an identified muon among the jet constituents in the dielectron channel

Transverse momentum distribution of the selected muon-inside-a-jet for events with an identified muon among the jet constituents in the dimuon channel

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A measurement of the Higgs boson mass in the diphoton decay channel

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2020.
Inspire Record 1780985 DOI 10.17182/hepdata.93362

A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9 fb$^{-1}$ of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a center-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be $m_\mathrm{H} =$ 125.78$\pm$0.26 GeV. This is combined with a measurement of $m_\mathrm{H}$ already performed in the H$\to$ZZ$\to$4$\ell$ decay channel using the same data set, giving $m_\mathrm{H} =$ 125.46$\pm$0.16 GeV. This result, when further combined with an earlier measurement of $m_\mathrm{H}$ using data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of $m_\mathrm{H} =$ 125.38$\pm$0.14 GeV. This is currently the most precise measurement of the mass of the Higgs boson.

1 data table

A summary of the mass of the Higgs boson measured in the H to GG and the H to ZZ to 4l decay channel, and for the combination of the two. These measurements have been carried out with the Run 1 and 2016 datasets as well as with them combined.


Version 2
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. D101 (2020) 052005, 2020.
Inspire Record 1767649 DOI 10.17182/hepdata.91374

This paper presents results of searches for the electroweak production of supersymmetric particles in models with compressed mass spectra. The searches use 139  fb-1 of 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 to 240 GeV for moderate mass splittings, and extend down to mass splittings of 1.5 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.

98 data tables

Number of signal events in SR-E-1L1T for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

Number of signal events in SR-E-high for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

Number of signal events in SR-E-low for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

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Measurements of inclusive jet spectra in pp and central Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
No Journal Information, 2019.
Inspire Record 1755387 DOI 10.17182/hepdata.93739

This article reports measurements of the $p_{\rm{T}}$-differential inclusive jet cross-section in pp collisions at $\sqrt{s}$ = 5.02 TeV and the $p_{\rm{T}}$-differential inclusive jet yield in Pb-Pb 0-10% central collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. Jets were reconstructed at mid-rapidity with the ALICE tracking detectors and electromagnetic calorimeter using the anti-$k_{\rm{T}}$ algorithm. For pp collisions, we report jet cross-sections for jet resolution parameters $R=0.1-0.6$ over the range $20<p_{\rm{T,jet}}<140$ GeV/$c$, as well as the jet cross-section ratios of different $R$, and comparisons to two next-to-leading-order (NLO)-based theoretical predictions. For Pb-Pb collisions, we report the $R=0.2$ and $R=0.4$ jet spectra for $40<p_{\rm{T,jet}}<140$ GeV/$c$ and $60<p_{\rm{T,jet}}<140$ GeV/$c$, respectively. The scaled ratio of jet yields observed in Pb-Pb to pp collisions, $R_{\rm{AA}}$, is constructed, and exhibits strong jet quenching and a clear $p_{\rm{T}}$-dependence for $R=0.2$. No significant $R$-dependence of the jet $R_{\rm{AA}}$ is observed within the uncertainties of the measurement. These results are compared to several theoretical predictions.

33 data tables

Fig. 1 Left, data for jet radius R=0.1. Unfolded pp full jet cross-section at $\sqrt{s}$ = 5.02 TeV for R = 0.1 − 0.6. No leading track requirement is imposed.

Fig. 1 Left, data for jet radius R=0.2. Unfolded pp full jet cross-section at $\sqrt{s}$ = 5.02 TeV for R = 0.1 − 0.6. No leading track requirement is imposed.

Fig. 1 Left, data for jet radius R=0.3. Unfolded pp full jet cross-section at $\sqrt{s}$ = 5.02 TeV for R = 0.1 − 0.6. No leading track requirement is imposed.