Pseudorapidity distributions of charged hadrons in proton-lead collisions at $\sqrt{s_{_\mathrm{NN}}} =$ 5.02 and 8.16 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1632453 DOI 10.17182/hepdata.80150

The pseudorapidity distributions of charged hadrons in proton-lead collisions at nucleon-nucleon center-of-mass energies $\sqrt{s_{_\mathrm{NN}}} =$ 5.02 and 8.16 TeV are presented. The measurements are based on data samples collected by the CMS experiment at the LHC. The number of primary charged hadrons produced in non-single-diffractive proton-lead collisions is determined in the pseudorapidity range $|\eta_\mathrm{lab}| <$ 2.4. The charged-hadron multiplicity distributions are compared to the predictions from theoretical calculations and Monte Carlo event generators. In the center-of-mass pseudorapidity range $|\eta_\mathrm{cm}| < 0.5$, the average charged-hadron multiplicity densities $<\mathrm{d}N_{\mathrm{ch}}/\mathrm{d}\eta_{\mathrm{cm}}>$$\vert_{|\eta_{\mathrm{cm}}| < 0.5}$ are 17.31$\pm $0.01 (stat) $\pm$ 0.59 (syst) and 20.10$\pm$0.01 (stat)$\pm$0.85 (syst) at $\sqrt{s_{_\mathrm{NN}}} =$ 5.02 and 8.16 TeV, respectively. The particle densities per participant nucleon are compared to similar measurements in proton-proton, proton-nucleus, and nucleus-nucleus collisions.

1 data table

Distributions of the pseudorapidity density of charged hadrons in the region $|\eta_{\mathrm{lab}}|<2.4$ in non-single-diffractive pPb collisions at $\sqrt{s_{_{\mathrm{NN}}}} = 5.02$ (open squares) and 8.16 TeV (full squares). The systematic uncertainties are correlated between the two beam energies. The proton beam goes in the positive $|\eta_{\mathrm{lab}}|$ direction.


Observation of top quark production in proton-nucleus collisions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1624694 DOI 10.17182/hepdata.79668

The first observation of top quark production in proton-nucleus collisions is reported using proton-lead data collected by the CMS experiment at the CERN LHC at a nucleon-nucleon center-of-mass energy of $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV. The measurement is performed using events with exactly one isolated electron or muon and at least four jets. The data sample corresponds to an integrated luminosity of 174 nb$^{-1}$. The significance of the $\mathrm{t}\overline{\mathrm{t}}$ signal against the background-only hypothesis is above five standard deviations. The measured cross section is $\sigma_{\mathrm{t}\overline{\mathrm{t}}} =$ 45$\pm$8 nb, consistent with predictions from perturbative quantum chromodynamics.

7 data tables

Invariant mass distributions of the W candidate, $m_{jj'}$, in the 0 b category after all selections. The error bars indicate the statistical uncertainties.

Invariant mass distributions of the W candidate, $m_{jj'}$, in the 1 b category after all selections. The error bars indicate the statistical uncertainties.

Invariant mass distributions of the W candidate, $m_{jj'}$, in the $\geq$2 b category after all selections. The error bars indicate the statistical uncertainties.

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Principal-component analysis of two-particle azimuthal correlations in PbPb and pPb collisions at CMS

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1618346 DOI 10.17182/hepdata.79057

For the first time a principle-component analysis is used to separate out different orthogonal modes of the two-particle correlation matrix from heavy ion collisions. The analysis uses data from sqrt(s[NN]) = 2.76 TeV PbPb and sqrt(s[NN]) = 5.02 TeV pPb collisions collected by the CMS experiment at the LHC. Two-particle azimuthal correlations have been extensively used to study hydrodynamic flow in heavy ion collisions. Recently it has been shown that the expected factorization of two-particle results into a product of the constituent single-particle anisotropies is broken. The new information provided by these modes may shed light on the breakdown of flow factorization in heavy ion collisions. The first two modes ("leading" and "subleading") of two-particle correlations are presented for elliptical and triangular anisotropies in PbPb and pPb collisions as a function of pt over a wide range of event activity. The leading mode is found to be essentially equivalent to the anisotropy harmonic previously extracted from two-particle correlation methods. The subleading mode represents a new experimental observable and is shown to account for a large fraction of the factorization breaking recently observed at high transverse momentum. The principle-component analysis technique has also been applied to multiplicity fluctuations. These also show a subleading mode. The connection of these new results to previous studies of factorization is discussed.

40 data tables

Leading ($\alpha$ = 1) and subleading ($\alpha$ = 2) elliptic flow, $v^{(\alpha)}_2$, as a function of $p_T$ in 0-0.2% centrality PbPb collisions.

Leading ($\alpha$ = 1) and subleading ($\alpha$ = 2) elliptic flow, $v^{(\alpha)}_2$, as a function of $p_T$ in 0-5% centrality PbPb collisions.

Leading ($\alpha$ = 1) and subleading ($\alpha$ = 2) elliptic flow, $v^{(\alpha)}_2$, as a function of $p_T$ in 0-10% centrality PbPb collisions.

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Measurement of the differential cross sections for the associated production of a W boson and jets in proton-proton collisions at sqrt(s) = 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1610623 DOI 10.17182/hepdata.79859

A measurement of the differential cross sections for a W boson produced in association with jets in the muon decay channel is presented. The measurement is based on 13 TeV proton-proton collision data corresponding to an integrated luminosity of 2.2 inverse-femtobarns, recorded by the CMS detector at the LHC. The cross sections are reported as functions of jet multiplicity, jet transverse momentum pT, jet rapidity, the scalar pT sum of the jets, and angular correlations between the muon and the jet for different jet multiplicities. The measured cross sections are in agreement with predictions that include multileg leading-order (LO) and next-to-LO matrix element calculations interfaced with parton showers, as well as a next-to-next-to-LO calculation for the W boson and one jet production.

19 data tables

The cross section measurement as a function of the exclusive jet multiplicity, for jet multiplicities of up to 6.

The cross section measurement as a function of the inclusive jet multiplicity, for jet multiplicities of up to 6.

The differential cross section measurement as a function of the transverse momentum of the first leading jet.

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Search for supersymmetry in events with at least one photon, missing transverse momentum, and large transverse event activity in proton-proton collisions at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1712 (2017) 142, 2017.
Inspire Record 1610629 DOI 10.17182/hepdata.79807

A search for physics beyond the standard model in final states with at least one photon, large transverse momentum imbalance, and large total transverse event activity is presented. Such topologies can be produced in gauge-mediated supersymmetry models in which pair-produced gluinos or squarks decay to photons and gravitinos via short-lived neutralinos. The data sample corresponds to an integrated luminosity of 35.9 inverse femtobarns of proton-proton collisions at sqrt(s) = 13 TeV recorded by the CMS experiment at the LHC in 2016. No significant excess of events above the expected standard model background is observed. The data are interpreted in simplified models of gluino and squark pair production, in which gluinos or squarks decay via neutralinos to photons. Gluino masses of up to 1.50-2.00 TeV and squark masses up to 1.30-1.65 TeV are excluded at 95% confidence level, depending on the neutralino mass and branching fraction.

14 data tables

Observed data compared to the background prediction. The expectation for the T5Wg signal scenario with a gluino mass of 1600 GeV and a gaugino mass of 100 GeV and the T6gg signal scenario with a squark mass of 1750 GeV and a neutralino mass of 1650 GeV are shown. The last three bins of the low-H_T^gamma selection are displayed, corresponding to three of the search regions The rightmost bin includes all events with ptmiss > 600GeV.

Observed data compared to the background prediction. The expectation for the T5Wg signal scenario with a gluino mass of 1600 GeV and a gaugino mass of 100 GeV and the T6gg signal scenario with a squark mass of 1750 GeV and a neutralino mass of 1650 GeV are shown. The last three bins of the high-H_T^gamma selection are displayed, corresponding to three of the search regions The rightmost bin includes all events with ptmiss > 600GeV.

Exclusion limits on the SUSY cross section at 95% CL for the T6gg model.

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Search for a heavy composite Majorana neutrino in the final state with two leptons and two quarks at $\sqrt{s}=13$ TeV

The CMS collaboration Sirunyan, A.M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett. B775 (2017) 315-337, 2017.
Inspire Record 1607793 DOI 10.17182/hepdata.80512

A search for physics beyond the standard model in the final state with two same-flavour leptons (electrons or muons) and two quarks produced in proton–proton collisions at s=13TeV is presented. The data were recorded by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 2.3fb−1 . The observed data are in good agreement with the standard model background prediction. The results of the measurement are interpreted in the framework of a recently proposed model in which a heavy Majorana neutrino, Nℓ , stems from a composite-fermion scenario. Exclusion limits are set for the first time on the mass of the heavy composite Majorana neutrino, mNℓ , and the compositeness scale Λ. For the case mNℓ=Λ , the existence of Ne ( Nμ ) is excluded for masses up to 4.60 (4.70) TeV at 95% confidence level.

6 data tables

Invariant mass distribution of two electrons and one large-radius jet. The events are selected accordingly to the signal region slection in the electron channel described in the paper.

Invariant mass distribution of two muons and one large-radius jet. The events are selected accordingly to the signal region slection in the muon channel described in the paper.

95% CL upper limits on the product of the production cross section $\sigma(pp\to N_e)$ and the branching ratio $B(N_e \to e q \bar{q}^{\prime})$ in electron channel, compared with theoretical predictions for HCMN model calculated with CalcHEP.

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Measurements of jet charge with dijet events in pp collisions at $\sqrt{s}=8$ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1710 (2017) 131, 2017.
Inspire Record 1605749 DOI 10.17182/hepdata.79857

Jet charge is an estimator of the electric charge of a quark, antiquark, or gluon initiating a jet. It is based on the momentum-weighted sum of the electric charges of the jet constituents. Measurements of three charge observables of the leading jet in transverse momentum pT are performed with dijet events. The analysis is carried out with data collected by the CMS experiment at the CERN LHC in proton-proton collisions at sqrt(s) = 8 TeV corresponding to an integrated luminosity of 19.7 inverse femtobarns. The results are presented as a function of the pT of the leading jet and compared to predictions from leading- and next-to-leading-order event generators combined with parton showers. Measured jet charge distributions, unfolded for detector effects, are reported, which expand on previous measurements of the jet charge average and standard deviation in pp collisions.

36 data tables

Jetcharge $Q (\kappa=1.0)$ of leading jet with pT > 400 GeV.

Jetcharge $Q (\kappa=0.6)$ of leading jet with pT > 400 GeV.

Jetcharge $Q (\kappa=0.3)$ of leading jet with pT > 400 GeV.

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Search for top squark pair production in pp collisions at $ \sqrt{s}=13 $ TeV using single lepton events

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1710 (2017) 019, 2017.
Inspire Record 1605128 DOI 10.17182/hepdata.79417

A search for top squark pair production in pp collisions at $ \sqrt{s}=13 $ TeV is performed using events with a single isolated electron or muon, jets, and a large transverse momentum imbalance. The results are based on data collected in 2016 with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 fb$^{−1}$. No significant excess of events is observed above the expectation from standard model processes. Exclusion limits are set in the context of supersymmetric models of pair production of top squarks that decay either to a top quark and a neutralino or to a bottom quark and a chargino. Depending on the details of the model, we exclude top squarks with masses as high as 1120 GeV. Detailed information is also provided to facilitate theoretical interpretations in other scenarios of physics beyond the standard model.

10 data tables

Result of the background estimates and data yields corresponding to 35.9 $\text{fb}^\text{$-$1}$ for the 27 signal regions.

Result of the background estimates and data yields corresponding to 35.9 $\text{fb}^\text{$-$1}$ for the 4 signal regions dedicated to compressed spectra.

The observed exclusion limits at 95% CL assuming 100% branching fraction for direct top squark pair production with decay $\widetilde{t}\widetilde{t} \rightarrow t \widetilde{\chi_1^0} t \widetilde{\chi_1^0}$.

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Measurement of B+/- meson differential production cross sections in pp and PbPb collisions at sqrt(s[NN]) = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1599548 DOI 10.17182/hepdata.77605

The differential production cross sections of B+/- mesons are measured via the exclusive decay channels B+/- to J/psi K+/- to mu+ mu - K+/- as a function of transverse momentum in pp and PbPb collisions at a center-of-mass energy sqrt(s[NN])=5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp (PbPb) dataset used for this analysis corresponds to an integrated luminosity of 28.0 inverse picobarns (351 inverse microbarns). The measurement is performed in the B+/- meson transverse momentum range of 7 to 50 GeV, in the rapidity interval abs(y)<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of two is observed in the PbPb system in comparison to the expectation from pp reference data. These results are compared to theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.

3 data tables

B meson production cross section in pp

B meson production cross section scaled by $\rm{T_{AA}}$ in PbPb

B meson nuclear modification factor in PbPb


Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of $W$ and $Z$ Bosons Using $pp$ Collisions at $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 119 (2017) 141802, 2017.
Inspire Record 1598467 DOI 10.17182/hepdata.80233

A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at s=13  TeV is presented. The data sample corresponds to an integrated luminosity of 15.2  fb-1 collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.

1 data table

Expected and observed exclusion limits at 95% confidence level as a function of $m(H^{\pm})$ for $\sigma_\mathrm{VBF}(H^{\pm}) \, \mathcal{B}(H^{\pm}\to W^{\pm}Z)$ for 15.2 $\mathrm{fb}^{-1}$ of proton-proton collisions at 13 TeV collected in 2015 and 2016.


Measurements of the pp $\to W\gamma\gamma$ and pp $\to Z\gamma\gamma$ cross sections and limits on anomalous quartic gauge couplings at $ \sqrt{s}=8 $ TeV

The CMS collaboration Sirunyan, A.M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1710 (2017) 072, 2017.
Inspire Record 1589287 DOI 10.17182/hepdata.79858

Measurements are presented of Wγγ and Zγγ production in proton-proton collisions. Fiducial cross sections are reported based on a data sample corresponding to an integrated luminosity of 19.4 fb$^{−1}$ collected with the CMS detector at a center-of-mass energy of 8 TeV. Signal is identified through the W → ℓν and Z → ℓℓ decay modes, where ℓ is a muon or an electron. The production of Wγγ and Zγγ, measured with significances of 2.6 and 5.9 standard deviations, respectively, is consistent with standard model predictions. In addition, limits on anomalous quartic gauge couplings in Wγγ production are determined in the context of a dimension-8 effective field theory.

2 data tables

Measured fiducial cross section for each channel and for the combination of channels for the WGG and ZGG analyses. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity.

Expected and observed 95% CL limits on anomalous quartic gauge couplings. Limits are obtained using WGG events in which the leading photon pT exceeds 70 GeV.


Version 2
Search for new physics with dijet angular distributions in proton-proton collisions at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1707 (2017) 013, 2017.
Inspire Record 1519995 DOI 10.17182/hepdata.77426

A search is presented for extra spatial dimensions, quantum black holes, and quark contact interactions in measurements of dijet angular distributions in proton-proton collisions at $ \sqrt{s}=13 $ TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 2.6 fb$^{−1}$. The distributions are found to be in agreement with predictions from perturbative quantum chromodynamics that include electroweak corrections. Limits for different contact interaction models are obtained. In a benchmark model, valid to next-to-leading order in QCD and in which only left-handed quarks participate, quark contact interactions are excluded up to a scale of 11.5 and 14.7 TeV for destructive or constructive interference, respectively. The production of quantum black holes is excluded for masses below 7.8 or 5.3 TeV, depending on the model. The lower limits for the scales of virtual graviton exchange in the Arkani-Hamed-Dimopoulos-Dvali model of extra spatial dimensions are in the range 7.9–11.2 TeV, and are the most stringent set of limits available.

6 data tables

Normalized dijet angular distribution for events with dijet mass > 4.8 TeV.

Normalized dijet angular distribution for events with 4.2 < dijet mass < 4.8 TeV.

Normalized dijet angular distribution for events with 3.6 < dijet mass < 4.2 TeV.

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Search for anomalous couplings in boosted $\mathrm{ WW/WZ }\to\ell\nu\mathrm{ q \bar{q} }$ production in proton-proton collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett. B772 (2017) 21-42, 2017.
Inspire Record 1518145 DOI 10.17182/hepdata.78151

This Letter presents a search for new physics manifested as anomalous triple gauge boson couplings in WW and WZ diboson production in proton–proton collisions. The search is performed using events containing a W boson that decays leptonically and a W or Z boson whose decay products are merged into a single reconstructed jet. The data, collected at s=8 TeV with the CMS detector at the LHC, correspond to an integrated luminosity of 19 fb−1 . No evidence for anomalous triple gauge couplings is found and the following 95% confidence level limits are set on their values: λ ( [−0.011,0.011] ), Δκγ ( [−0.044,0.063] ), and Δg1Z ( [−0.0087,0.024] ). These limits are also translated into their effective field theory equivalents: cWWW/Λ2 ( [−2.7,2.7] TeV−2 ), cB/Λ2 ( [−14,17] TeV−2 ), and cW/Λ2 ( [−2.0,5.7] TeV−2 ).

1 data table

One-dimensional 95% CL limits on anomalous trilinear gauge couplings from the W V -> l nu q q channel.


Measurement of double-differential cross sections for top quark pair production in pp collisions at sqrt(s) = 8 TeV and impact on parton distribution functions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1516191 DOI 10.17182/hepdata.77008

Normalized double-differential cross sections for top quark pair (ttbar) production are measured in pp collisions at a centre-of-mass energy of 8 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7 inverse femtobarns. The measurement is performed in the dilepton e+/- mu-/+ final state. The ttbar cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and ttbar system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured ttbar cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution.

18 data tables

The measured normalized $t\bar{t}$ double-differential cross sections in different bins of $y(t)$ and $p_{T}(t)$, along with their relative statistical and systematic uncertainties expressed as percentages.

The correlation matrix of statistical uncertainties for the normalized $t\bar{t}$ double-differential cross sections as a function of $y(t)$ and $p_{T}(t)$. The values are expressed as percentages. For bin indices see Table 5.

Sources and values of the relative systematic uncertainties in percent of the measured normalized $t\bar{t}$ double-differential cross sections as a function of $y(t)$ and $p_{T}(t)$. For bin indices see Table 5.

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Measurement of the cross section for electroweak production of Z$\gamma$ in association with two jets and constraints on anomalous quartic gauge couplings in proton-proton collisions at $\sqrt{s} = $ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2017.
Inspire Record 1512924 DOI 10.17182/hepdata.77543

A measurement is presented of the cross section for the electroweak production of a Z boson and a photon in association with two jets in proton-proton collisions at sqrt(s)= 8 TeV. The Z bosons are identified through their decays to electron or muon pairs. The measurement is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 inverse femtobarns. The electroweak contribution has a significance of 3.0 standard deviations, and the measured fiducial cross section is 1.86 +0.90/-0.75 (stat)+0.34/-0.26 (syst) +/- 0.05 (lumi) fb, while the summed electroweak and quantum chromodynamic total cross section in the same region is observed to be 5.94 +1.53/-1.35 (stat) +0.43/-0.37 (syst) +/- 0.13 (lumi) fb. Both measurements are consistent with the leading-order standard model predictions. Limits on anomalous quartic gauge couplings are set based on the Z gamma mass distribution.

1 data table

The measured fiducial cross section of EW ZGamma+2Jets process.


Measurement of prompt and nonprompt J/psi production in pp and pPb collisions at sqrt(s[NN]) = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1512296 DOI 10.17182/hepdata.77480

This paper reports the measurement of J/psi meson production in proton-proton (pp) and proton-lead (pPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV by the CMS experiment at the LHC. The data samples used in the analysis correspond to integrated luminosities of 28 inverse picobarns and 35 inverse nanobarns for pp and pPb collisions, respectively. Prompt and nonprompt J/psi mesons, the latter issuing from the decay of B mesons, are measured in their dimuon decay channels. Differential cross sections are measured in the transverse momentum range of 2<pt<30 GeV/c, and center-of-mass rapidity ranges of abs(y[CM])<2.4 (pp) and -2.87<y[CM]<1.93 (pPb). The nuclear modification factor, R[pPb], is measured as functions of pt and y[CM]. Small modifications of the J/psi cross sections are observed in pPb relative to pp collisions. The ratio of J/psi production cross sections in p-going and Pb-going directions, R[FB], studied as functions of pt and y[CM], shows a significant decrease for increasing transverse energy deposited at large pseudorapidities. These results, which cover a wide kinematic range, provide new insight on the role of cold nuclear matter effects on prompt and nonprompt J/psi production.

26 data tables

Differential cross section (multiplied by the dimuon branching fraction) of prompt J/$\psi$ mesons in pp collisions at forward $y_{\mathrm{CM}}$.

Differential cross section (multiplied by the dimuon branching fraction) of prompt J/$\psi$ mesons in pp collisions at backward $y_{\mathrm{CM}}$.

Differential cross section (multiplied by the dimuon branching fraction) of prompt J/$\psi$ mesons in pPb collisions at forward $y_{\mathrm{CM}}$.

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Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1512112 DOI 10.17182/hepdata.77604

The production of jets in association with Z bosons, reconstructed via the mu+mu- and e+e- decay channels, is studied in pp and, for the first time, in PbPb collisions. Both data samples were collected by the CMS experiment at the LHC, at a center-of-mass energy of 5.02 TeV. The PbPb collisions were analyzed in the 0-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and PbPb collisions for Z bosons with transverse momentum ptz > 60 GeV/c and a recoiling jet with ptj > 30 GeV/c. The pt imbalance, xjz= ptj/ptz, as well as the average number of jet partners per Z, rjz, were studied in intervals of ptz, in both pp and PbPb collisions. The rjz is found to be smaller in PbPb than in pp collisions, which suggests that in PbPb collisions a larger fraction of partons, associated with the Z bosons, lose energy and fall below the 30 GeV/c ptj threshold.

9 data tables

Distribution of the azimuthal angle difference between the Z boson and the jet in pp collisions. The distribution is normalized by the number of Z events. The resolutions of the measured jet energy and azimuthal angle are smeared to match those of the PbPb sample.

Distribution of the azimuthal angle difference between the Z boson and the jet in PbPb collisions. The distribution is normalized by the number of Z events.

Distribution of the transverse momentum ratio between the Z boson and the jet in pp collisions. The distribution is normalized by the number of Z events. The resolutions of the measured jet energy and azimuthal angle are smeared to match those of the PbPb sample.

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Azimuthal anisotropy of charged particles with transverse momentum up to 100 GeV in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1511868 DOI 10.17182/hepdata.77603

The Fourier coefficients v[2] and v[3] characterizing the anisotropy of the azimuthal distribution of charged particles produced in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV are measured with data collected by the CMS experiment. The measurements cover a broad transverse momentum range, pt= 1-100 GeV. The analysis focuses on pt > 10 GeV range, where anisotropic azimuthal distributions should reflect the path-length dependence of parton energy loss in the created medium. Results are presented in several bins of PbPb collision centrality, spanning the 60x% most central events. The v[2] coefficient is measured with the scalar product and the multiparticle cumulant methods, which have different sensitivities to the initial-state fluctuations. The values of both methods remain positive up to pt ~ 70 GeV, in all examined centrality classes. The v[3] coefficient, only measured with the scalar product method, tends to zero for pt >~ 20 GeV. Comparisons between theoretical calculations and data provide new constraints on the path-length dependence of parton energy loss in heavy ion collisions and highlight the importance of the initial-state fluctuations.

22 data tables

The $v_{2}$ result from SP method as a function of $p_{T}$ in 0-5\% centrality bin of PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. Shaded boxes represent systematic uncertainties.

The $v_{2}$ result from SP method as a function of $p_{T}$ in 5-10\% centrality bin of PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. Shaded boxes represent systematic uncertainties.

The $v_{2}$ result from SP method as a function of $p_{T}$ in 10-20\% centrality bin of PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. Shaded boxes represent systematic uncertainties.

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Measurement of the inclusive energy spectrum in the very forward direction in proton-proton collisions at sqrt(s)=13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1511284 DOI 10.17182/hepdata.76842

The differential cross section for inclusive particle production as a function of energy in proton-proton collisions at a center-of-mass energy of 13 TeV is measured in the very forward region of the CMS detector. The measurement is based on data collected with the CMS apparatus at the LHC, and corresponds to an integrated luminosity of 0.35 inverse microbarns. The energy is measured in the CASTOR calorimeter, which covers the pseudorapidity region -6.6<eta<-5.2. The results are given as a function of the total energy deposited in CASTOR, as well as of its electromagnetic and hadronic components. The spectra are sensitive to the modeling of multiparton interactions in pp collisions, and provide new constraints for hadronic interaction models used in collider and in high energy cosmic ray physics.

6 data tables

Differential cross section as a function of the total energy in the region −6.6 < eta < −5.2 for events with xi>10−6.

Differential cross section as a function of the electromagnetic energy in the region −6.6 < eta < −5.2 for events with xi>10−6.

Differential cross section as a function of the hadronic energy in the region −6.6 < eta < −5.2 for events with xi>10−6.

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Measurement of electroweak-induced production of W$\gamma$ with two jets in pp collisions at $ \sqrt{s}=8 $ TeV and constraints on anomalous quartic gauge couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1706 (2017) 106, 2017.
Inspire Record 1507095 DOI 10.17182/hepdata.78254

A measurement of electroweak-induced production of Wγ and two jets is performed, where the W boson decays leptonically. The data used in the analysis correspond to an integrated luminosity of 19.7 fb$^{−1}$ collected by the CMS experiment in $ \sqrt{s}=8 $ TeV proton-proton collisions produced at the LHC. Candidate events are selected with exactly one muon or electron, missing transverse momentum, one photon, and two jets with large rapidity separation. An excess over the hypothesis of the standard model without electroweak production of Wγ with two jets is observed with a significance of 2.7 standard deviations. The cross section measured in the fiducial region is 10.8 ± 4.1(stat) ± 3.4(syst) ± 0.3(lumi) fb, which is consistent with the standard model electroweak prediction. The total cross section for Wγ in association with two jets in the same fiducial region is measured to be 23.2 ± 4.3(stat) ± 1.7(syst) ± 0.6(lumi) fb, which is consistent with the standard model prediction from the combination of electroweak and quantum chromodynamics-induced processes. No deviations are observed from the standard model predictions and experimental limits on anomalous quartic gauge couplings f$_{M,0−7}$ /Λ$^{4}$, f$_{T,0−2}$ /Λ$^{4}$, and f$_{T,5−7}$ /Λ$^{4}$ are set at 95% confidence level.

2 data tables

Summary of the measured and predicted observables.

Observed and expected shape-based exclusion limits for the aQGC parameters at 95% CL, without any form factors.


Measurement of the $t\bar{t}$ production cross section using events in the e$\mu$ final state in pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1497736 DOI 10.17182/hepdata.76735

The cross section of top quark-antiquark pair production in proton-proton collisions at $\sqrt{s}$ = 13 TeV is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2 inverse femtobarns. The measurement is performed by analyzing events in which the final state includes one electron, one muon, and two or more jets, at least one of which is identified as originating from hadronization of a b quark. The measured cross section is 792 +/- 8 (stat) +/- 37 (syst) +/- 21 (lumi) pb, in agreement with the expectation from the standard model.

3 data tables

Summary of the individual contributions to the uncertainty in the $\sigma_{t\bar{t}}$ measurement.

Measurement of the $t\bar{t}$ production cross-section in $pp$ collisions at $\sqrt{s} = 13$ TeV.

Number of dilepton events obtained after applying the full selection. The results are given for the individual sources of background, $t\bar{t}$ signal with a top quark mass of 172.5 GeV and $\sigma_{t\bar{t}}$ = 832 +/- 46 pb, and data. The uncertainties correspond to statistical and systematic components.


Version 2
Charged-particle nuclear modification factors in PbPb and pPb collisions at $\sqrt{s_{\mathrm{NN}}}= $ 5.02 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP, 2016.
Inspire Record 1496050 DOI 10.17182/hepdata.77101

The spectra of charged particles produced within the pseudorapidity window $| \eta | < $ 1 at $\sqrt{s_{\mathrm{NN}}}= $ 5.02 TeV are measured using 404 $ \mu $b$^{-1}$ of PbPb and 27.4 pb$^{-1}$ of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 $ < p_{\mathrm{T}} < $ 400 GeV in pp and 0.7 $ < p_{\mathrm{T}} < $ 400 GeV in PbPb collisions. The corresponding nuclear modification factor, ${R_\mathrm{AA}} $, is measured in bins of collision centrality. The ${R_\mathrm{AA}} $ in the 5% most central collisions shows a maximal suppression by a factor of 7-8 in the $p_{\mathrm{T}}$ region of 6-9 GeV. This dip is followed by an increase, which continues up to the highest $ p_{\mathrm{T}}$ measured, and approaches unity in the vicinity of $p_{\mathrm{T}}= $ 200 GeV. The ${R_\mathrm{AA}} $ is compared to theoretical predictions and earlier experimental results at lower collision energies. The newly measured pp spectrum is combined with the pPb spectrum previously published by the CMS Collaboration to construct the pPb nuclear modification factor, ${R_{\mathrm{ p }\mathrm{A}}} $, up to 120 GeV. For $ p_{\mathrm{T}} > $ 20 GeV, ${R_{\mathrm{ p }\mathrm{A}}} $ exhibits weak momentum dependence and shows a moderate enhancement above unity.

16 data tables

Charged-particle per-event yields measured in 0-5% PbPb centrality class.

Charged-particle per-event yields measured in 5-10% PbPb centrality class.

Charged-particle per-event yields measured in 10-30% PbPb centrality class.

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Version 2
Suppression of $\Upsilon(1S)$, $\Upsilon(2S)$ and $\Upsilon(3S)$ production in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B, 2016.
Inspire Record 1495866 DOI 10.17182/hepdata.77220

The production yields of Upsilon(1S), Upsilon(2S), and Upsilon(3S) quarkonium states are measured through their decays into muon pairs in the CMS detector, in PbPb and pp collisions at the centre-of-mass energy per nucleon pair of 2.76 TeV. The data correspond to integrated luminosities of 166 inverse microbarns and 5.4 inverse picobarns for PbPb and pp collisions, respectively. Differential production cross sections are reported as functions of Upsilon rapidity $y$ up to 2.4, and transverse momentum pt up to 20 GeV/c. A strong centrality-dependent suppression is observed in PbPb relative to pp collisions, by factors of up to ~2 and 8, for the Upsilon(1S) and Upsilon(2S) states, respectively. No significant dependence of this suppression is observed as a function of y or pt. The Upsilon(3S) state is not observed in PbPb collisions, which corresponds to a suppression for the centrality-integrated data by at least a factor of ~7 at a 95% confidence level. The observed suppression is in agreement with theoretical scenarios modeling the sequential melting of quarkonium states in a quark gluon plasma.

17 data tables

Differential cross section for Y(1S) states as a function of their transverse momentum and per unit of rapidity in pp collisions. Statistical (systematic) uncertainties are displayed as error bars (boxes). Global relative uncertainties of 3.7% are not displayed.

Differential cross section for Y(2S) states as a function of their transverse momentum and per unit of rapidity in pp collisions. Statistical (systematic) uncertainties are displayed as error bars (boxes). Global relative uncertainties of 3.7% are not displayed.

Differential cross section for Y(3S) states as a function of their transverse momentum and per unit of rapidity in pp collisions. Statistical (systematic) uncertainties are displayed as error bars (boxes). Global relative uncertainties of 3.7% are not displayed.

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Relative modification of prompt $ {\psi\mathrm{(2S)}} $ and $\mathrm{J}/\psi $ yields from pp to PbPb collisions at ${\sqrt{s_{\mathrm{NN}}}} = $ 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett., 2016.
Inspire Record 1495840 DOI 10.17182/hepdata.77102

The relative modification of the prompt psi(2S) and J/psi yields from pp to PbPb collisions, at the center of mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0 inverse picobarns and 464 inverse microbarns, respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs, (N[psi(2S)]/N[J/psi])[PbPb]/ (N[psi(2S)]/N[J/psi])[pp], is determined as a function of PbPb collision centrality and charmonium transverse momentum pt, in two kinematic intervals: abs(y) < 1.6 covering 6.5 < pt < 30GeV/c and 1.6 < abs(y) < 2.4 covering 3 <pt< 30GeV/c. The centrality-integrated double ratios are 0.36 +/- 0.08 (stat) +/-0.05 (syst) in the first interval and 0.24 +/- 0.22 (stat) +/- 0.09 (syst) in the second. The double ratio is lower than unity in all the measured bins, suggesting that the psi(2S) yield is more suppressed than the J/psi yield in the explored phase space.

10 data tables

Double ratio of measured yields, $(N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{\mathrm{PbPb}} / (N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{pp}$, as a function of pT, for the midrapidity analysis bin.

95% CL intervals on the double ratio of measured yields, $(N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{\mathrm{PbPb}} / (N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{pp}$, as a function of pT, for the midrapidity analysis bin.

Double ratio of measured yields, $(N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{\mathrm{PbPb}} / (N_{\psi\mathrm{(2S)}} / N_{J/\psi})_{pp}$, as a function of pT, for the forward rapidity analysis bin.

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A search for new phenomena in pp collisions at $\sqrt{s} = 13\,\text {TeV} $ in final states with missing transverse momentum and at least one jet using the $\alpha _{\mathrm {T}}$ variable

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C77 (2017) 294, 2017.
Inspire Record 1495423 DOI 10.17182/hepdata.77606

A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13 $\,\text {TeV}$ . The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3 $\,\text {fb}^{-1}$ . Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975 $\,\text {GeV}$ are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400 $\,\text {GeV}$ are excluded.

97 data tables

Observed data counts and "post-fit" background expectations based on the result of a combined fit to the signal region and multiple control regions under the SM-only hypothesis for the "monojet" event category. The rows labelled SM "pre-fit' show the background expectations when excluding the signal region from the fit. The uncertainties include statistical as well as systematic contributions.

Summary of the lower bounds of the first and final bins in $H_{\mathrm{T}}$ in [GeV] (the latter in parentheses) as a function of $n_{\text{jet}}$ and $n_{\text{b}}$.

Observed data counts and "post-fit" background expectations based on the result of a combined fit to the signal region and multiple control regions under the SM-only hypothesis for the "asymmetric" event categories. The rows labelled SM "pre-fit" show the background expectations when excluding the signal region from the fit. The uncertainties include statistical as well as systematic contributions.

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