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


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 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.


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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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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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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Measurements of differential cross sections for associated production of a W boson and jets in proton-proton collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.D, 2016.
Inspire Record 1491953 DOI 10.17182/hepdata.76995

Differential cross sections for a W boson produced in association with jets are measured in a data sample of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 inverse femtobarns. The W bosons are identified through their decay mode W to mu nu. The cross sections are reported as functions of jet multiplicity, transverse momenta, and the scalar sum of jet transverse momenta (HT) for different jet multiplicities. Distributions of the angular correlations between the jets and the muon are examined, as well as the average number of jets as a function of HT and as a function of angular variables. The measured differential cross sections are compared with tree-level and higher-order recent event generators, as well as next-to-leading-order and next-to-next-to-leading-order theoretical predictions. The agreement of the generators with the measurements builds confidence in their use for the simulation of W+jets background processes in searches for new physics at the LHC.

39 data tables

The cross section measurement as a function of the exclusive jet multiplicity, for jet multiplicities of up to 7.

The cross section measurement as a function of the inclusive jet multiplicity, for jet multiplicities of up to 7.

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

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Measurement of differential cross sections for top quark pair production using the lepton+jets final state in proton-proton collisions at 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.D, 2016.
Inspire Record 1491950 DOI 10.17182/hepdata.76554

Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at 13 TeV are measured as a function of jet multiplicity and of kinematic variables of the top quarks and the top quark-antiquark system. This analysis is based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurements are performed in the lepton+jets decay channels with a single muon or electron in the final state. The differential cross sections are presented at particle level, within a phase space close to the experimental acceptance, and at parton level in the full phase space. The results are compared to several standard model predictions.

164 data tables

Absolute cross section at particle level.

Covariance matrix of absolute cross section at particle level.

Absolute cross section at particle level.

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Search for anomalous Wtb couplings and flavour-changing neutral currents in t-channel single top quark production in pp collisions at $\sqrt{s} =$ 7 and 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1702 (2017) 028, 2017.
Inspire Record 1491379 DOI 10.17182/hepdata.77022

Single top quark events produced in the t channel are used to set limits on anomalous Wtb couplings and to search for top quark flavour-changing neutral current (FCNC) interactions. The data taken with the CMS detector at the LHC in proton-proton collisions at $ \sqrt{s}=7 $ and 8 TeV correspond to integrated luminosities of 5.0 and 19.7 fb$^{−1}$, respectively. The analysis is performed using events with one muon and two or three jets. A Bayesian neural network technique is used to discriminate between the signal and backgrounds, which are observed to be consistent with the standard model prediction. The 95% confidence level (CL) exclusion limits on anomalous right-handed vector, and left- and right-handed tensor Wtb couplings are measured to be |f$_{V}^{R}$ | < 0.16, |f$_{T}^{L}$ | < 0.057, and − 0.049 < f$_{T}^{R}$  < 0.048, respectively. For the FCNC couplings κ$_{tug}$ and κ$_{tcg}$, the 95% CL upper limits on coupling strengths are |κ$_{tug}$|/Λ < 4.1 × 10$^{− 3}$ TeV$^{−1}$ and |κ$_{tcg}$|/Λ < 1.8 × 10$^{− 2}$ TeV$^{−1}$, where Λ is the scale for new physics, and correspond to upper limits on the branching fractions of 2.0 × 10$^{−5}$ and 4.1 × 10$^{−4}$ for the decays t → ug and t → cg, respectively.

5 data tables

Predicted and observed event yields before and after multijet BNN selection for $\sqrt{s}=7$ and $8$ TeV.

List of input variables for the Bayesian neural networks used in the analysis. Numbers in the cells indicate whether the variable was used in a network in 7 TeV analysis, 8 TeV one, or in both of them.

One-dimensional exclusion limits on anomalous $Wtb$ couplings, evaluated in different two- and three-dimensional scenarios in the analyses conducted at $\sqrt{s}=7$ and $8$ TeV.).

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Version 2
Suppression and azimuthal anisotropy of prompt and nonprompt $J/\psi$ production in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J.C, 2016.
Inspire Record 1489189 DOI 10.17182/hepdata.77015

The nuclear modification factor ${R_{\mathrm{AA}}} $ and the azimuthal anisotropy coefficient ${v_{2}} $ of prompt and nonprompt (i.e. those from decays of b hadrons) $\mathrm{J}/\psi$ mesons, measured from PbPb and pp collisions at $\sqrt{s_{\mathrm{NN}}} = $ 2.76 TeV at the LHC, are reported. The results are presented in several event centrality intervals and several kinematic regions, for transverse momenta $p_{\mathrm{T}} > $ 6.5 GeV/$c$ and rapidity $| {y} | < $ 2.4, extending down to $p_{\mathrm{T}}= $ 3 GeV/$c$ in the 1.6 $ < |{y}| < $ 2.4 range. The ${v_{2}} $ of prompt $\mathrm{J}/\psi$ is found to be nonzero and constant over the full kinematic range studied, while the measured ${v_{2}} $ of nonprompt $\mathrm{J}/\psi$ is consistent with zero. The ${R_{\mathrm{AA}}} $of prompt $\mathrm{J}/\psi$ exhibits a suppression that increases with centrality but does not vary as a function of either $y$ or $p_{\mathrm{T}}$ in the fiducial range. The nonprompt $\mathrm{J}/\psi {R_{\mathrm{AA}}} $ shows a suppression which becomes stronger as rapidity or $ p_{\mathrm{T}}$ increase. The ${v_{2}} $ and nuclear suppression of open and hidden charm, and of open charm and beauty, are compared.

14 data tables

Prompt J/$\psi$ $v_{2}$ as a function of centrality. The average ${N}_{\rm part}$ values correspond to events flatly distributed across centrality.

Prompt J/$\psi$ $v_{2}$ as a function of rapidity.

Prompt J/$\psi$ $v_{2}$ as a function of $p_{T}$.

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Observation of charge-dependent azimuthal correlations in pPb collisions and its implication for the search for the chiral magnetic effect

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett, 2016.
Inspire Record 1489183 DOI 10.17182/hepdata.77013

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in pPb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range abs(eta)<2.4, and a third particle measured in the hadron forward calorimeters (4.4< abs(eta)<5). The observed differences between the same and opposite sign correlations, as functions of multiplicity and eta gap between the two charged particles, are of similar magnitude in pPb and PbPb collisions at the same multiplicities. These results pose a challenge for the interpretation of charge-dependent azimuthal correlations in heavy ion collisions in terms of the chiral magnetic effect.

10 data tables

Three-particle correlation with respect to the 2nd order event plane from Pb-going side in pPb collisions at multiplicity [185,220), with individual track pT between 0.3 to 3.0 GeV/c. Data points are plotted at the bin center.

Three-particle correlation with respect to the 2nd order event plane from p-going side in pPb collisions at multiplicity [185,220), with individual track pT between 0.3 to 3.0 GeV/c. Data points are plotted at the bin center.

Three-particle correlation with respect to the 2nd order event plane in PbPb collisions at multiplicity [185,220), with individual track pT between 0.3 to 3.0 GeV/c. Data points are plotted at the bin center.

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Measurement and QCD analysis of double-differential inclusive jet cross-sections in pp collisions at $\sqrt{s} = $ 8 TeV and ratios to 2.76 and 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP, 2016.
Inspire Record 1487277 DOI 10.17182/hepdata.77222

A measurement of the double-differential inclusive jet cross section as a function of the jet transverse momentum $p_{\mathrm{T}}$ and the absolute jet rapidity $|y|$ is presented. Data from LHC proton-proton collisions at $ \sqrt{s} = $ 8 TeV, corresponding to an integrated luminosity of 19.7 fb$^{-1}$, have been collected with the CMS detector. Jets are reconstructed using the anti-$k_{\mathrm{T}}$ clustering algorithm with a size parameter of 0.7 in a phase space region covering jet $p_{\mathrm{T}}$ from 74 GeV up to 2.5 TeV and jet absolute rapidity up to $|y|= $ 3.0. The low-$p_{\mathrm{T}}$ jet range between 21 and 74 GeV is also studied up to $|y|= $ 4.7, using a dedicated data sample corresponding to an integrated luminosity of 5.6 pb$^{-1}$. The measured jet cross section is corrected for detector effects and compared with the predictions from perturbative QCD at next-to-leading order (NLO) using various sets of parton distribution functions (PDF). Cross section ratios to the corresponding measurements performed at 2.76 and 7 TeV are presented. From the measured double-differential jet cross section, the value of the strong coupling constant evaluated at the Z mass is $\alpha_\mathrm{S}(M_{\mathrm{ Z }}) = 0.1164^{+0.0060}_{-0.0043}$, where the errors include the PDF, scale, nonperturbative effects and experimental uncertainties, using the CT10 NLO PDFs. Improved constraints on PDFs based on the inclusive jet cross section measurement are presented.

7 data tables

Inclusive Jet Cross Section for 0.0 < |y| < 0.5 as a function of the jet transverse momentum. The (sys) error is the total systematic error, including the luminosity uncertainty of 2.6%.

Inclusive Jet Cross Section for 0.5 < |y| < 1.0 as a function of the jet transverse momentum. The (sys) error is the total systematic error, including the luminosity uncertainty of 4.4%.

Inclusive Jet Cross Section for 1.0 < |y| < 1.5 as a function of the jet transverse momentum. The (sys) error is the total systematic error, including the luminosity uncertainty of 4.4%.

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Studies of inclusive four-jet production with two b-tagged jets in proton-proton collisions at 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1486238 DOI 10.17182/hepdata.75375

Measurements are presented of the cross section for the production of at least four jets, of which at least two originate from b quarks, in proton-proton collisions. Data collected with the CMS detector at the LHC at a center-of-mass energy of 7 TeV are used, corresponding to an integrated luminosity of 3 inverse picobarns. The cross section is measured as a function of the jet transverse momentum for pt 20 GeV, and of the jet pseudorapidity for abs(eta)<2.4 (b jets), 4.7 (untagged jets). The correlations in azimuthal angle and pt between the jets are also studied. The inclusive cross section is measured to be sigma(pp to 2 b + 2 j + X) = 69 +/- 3 (stat) +/- 24 (syst) nb. The eta and pt distributions of the four jets and the correlations between them are well reproduced by event generators that combine perturbative QCD calculations at next-to-leading-order accuracy with contributions from parton showers and multiparton interactions.

12 data tables

The measured fiducial cross section. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, sample purity, model dependence and jet energy resolution and trigger efficiency correction.

Differential cross section as a function of the transverse momentum PT of the leading b-jet. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, sample purity, model dependence and jet energy resolution and trigger efficiency correction.

Differential cross section as a function of the transverse momentum PT of the subleading b-jet. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, sample purity, model dependence and jet energy resolution and trigger efficiency correction.

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Decomposing transverse momentum balance contributions for quenched jets in PbPb collisions at $ \sqrt{s_{\mathrm{N}\;\mathrm{N}}}=2.76 $ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1611 (2016) 055, 2016.
Inspire Record 1485701 DOI 10.17182/hepdata.77493

Interactions between jets and the quark-gluon plasma produced in heavy ion collisions are studied via the angular distributions of summed charged-particle transverse momenta (p$_{T}$) with respect to both the leading and subleading jet axes in high-p$_{T}$ dijet events. The contributions of charged particles in different momentum ranges to the overall event p$_{T}$ balance are decomposed into short-range jet peaks and a long-range azimuthal asymmetry in charged-particle p$_{T}$. The results for PbPb collisions are compared to those in pp collisions using data collected in 2011 and 2013, at collision energy $ \sqrt{s_{\mathrm{N}\,\mathrm{N}}}=2.76 $ TeV with integrated luminosities of 166 μb$^{−1}$ and 5.3 pb$^{−1}$, respectively, by the CMS experiment at the LHC. Measurements are presented as functions of PbPb collision centrality, charged-particle p$_{T}$, relative azimuth, and radial distance from the jet axis for balanced and unbalanced dijets.

64 data tables

Leading jet shape rho(dR) versus dR for pp data, normalized to unity over the range dR < 0.3.

Leading jet shape rho(dR) versus dR for peripheral PbPb data (centrality 50-100%), normalized to unity over the range dR < 0.3.

Leading jet shape rho(dR) versus dR for central PbPb data (centrality 0-30%), normalized to unity over the range dR < 0.3.

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Measurement of the production cross section of the W boson in association with two b jets in pp collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1484162 DOI 10.17182/hepdata.76543

The production cross section of a W boson in association with two b jets is measured using a sample of proton-proton collisions at $ \sqrt{s} = $ 8 TeV collected by the CMS experiment at the CERN LHC. The data sample corresponds to an integrated luminosity of 19.8 fb$^{-1}$. The W bosons are reconstructed via their leptonic decays, $ \mathrm{ W }\to\ell\nu $, where $\ell=\mu$ or $\mathrm{ e }$. The fiducial region studied contains exactly one lepton with transverse momentum $ p_{\mathrm{T}}^{\ell} > $ 30 GeV and pseudorapidity $ | {\eta^{\ell}} | < $ 2.1, with exactly two b jets with $ p_{\mathrm{T}} > $ 25 GeV and $ | {\eta} | < $ 2.4 and no other jets with $ p_{\mathrm{T}} > $ 25 GeV and $ | {\eta} | < $ 4.7. The cross section is measured to be $ \sigma ( {{\mathrm{ p }\mathrm{ p }}} \to {\mathrm{ W }} (\ell\nu) + \mathrm{ b \bar{b} }) =$ 0.64 $\pm$ 0.03 (stat) $\pm$ 0.10 (syst) $\pm$ 0.06 (theory) $\pm$ 0.02 (lumi) pb, in agreement with standard model predictions.

1 data table

Wbb production cross section in pb.