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Evidence for exclusive $\gamma\gamma \to W^+ W^-$ production and constraints on anomalous quartic gauge couplings in $pp$ collisions at $ \sqrt{s}=7 $ and 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1608 (2016) 119, 2016.
Inspire Record 1448100 DOI 10.17182/hepdata.74707

A search for exclusive or quasi-exclusive γγ → W$^{+}$ W$^{−}$ production, via pp → p$^{(*)}$ W$^{+}$ W$^{−}$ p$^{(*)}$ → p$^{(*)}$ μ$^{±}$e$^{∓}$ p$^{(*)}$ at $ \sqrt{s}=8 $ TeV, is reported using data corresponding to an integrated luminosity of 19.7 fb$^{−1}$. Events are selected by requiring the presence of an electron-muon pair with large transverse momentum p$_{T}$(μ$^{±}$e$^{∓}$) > 30 GeV, and no associated charged particles detected from the same vertex. The 8 TeV results are combined with the previous 7 TeV results (obtained for 5.05 fb$^{−1}$ of data). In the signal region, 13 (2) events are observed over an expected background of 3.9 ± 0.6 (0.84 ± 0.15) events for 8 (7) TeV, resulting in a combined excess of 3.4σ over the background-only hypothesis. The observed yields and kinematic distributions are compatible with the standard model prediction for exclusive and quasi-exclusive γγ → W$^{+}$ W$^{−}$ production. Upper limits on the anomalous quartic gauge coupling operators a$_{0,C}^{W}$ (dimension-6) and f$_{M0,1,2,3}$ (dimension-8), the most stringent to date, are derived from the measured dilepton transverse momentum spectrum.

1 data table

8 TeV cross section multiplied by branching fraction to opposite-sign mue final states, corrected for all experimental efficiencies and extrapolated to the full phase space.


Search for two Higgs bosons in final states containing two photons and two bottom quarks in proton-proton collisions at 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D94 (2016) 052012, 2016.
Inspire Record 1431986 DOI 10.17182/hepdata.77003

A search is presented for the production of two Higgs bosons in final states containing two photons and two bottom quarks. Both resonant and nonresonant hypotheses are investigated. The analyzed data correspond to an integrated luminosity of 19.7  fb-1 of proton-proton collisions at s=8  TeV collected with the CMS detector. Good agreement is observed between data and predictions of the standard model (SM). Upper limits are set at 95% confidence level on the production cross section of new particles and compared to the prediction for the existence of a warped extra dimension. When the decay to two Higgs bosons is kinematically allowed, assuming a mass scale ΛR=1  TeV for the model, the data exclude a radion scalar at masses below 980 GeV. The first Kaluza-Klein excitation mode of the graviton in the RS1 Randall-Sundrum model is excluded for masses between 325 and 450 GeV. An upper limit of 0.71 pb is set on the nonresonant two-Higgs-boson cross section in the SM-like hypothesis. Limits are also derived on nonresonant production assuming anomalous Higgs-boson couplings.

3 data tables

Observed $m_\mathrm{jj}$ spectrum (black points) compared with a background estimate (black line), obtained in background only hypothesis, for HPHP category. The simulated radion resonances of $m_\mathrm{X} = 1.5$ and 2 TeV are also shown. Observed and expected 95% CL upper limits on the product of cross section and the branching fraction sigma(pp->X)*B(X->HH) obtained through a combination of the two event categories. The limits for mX = 400 GeV are shown for both Low mass and High mass signal extraction methods.

Observed and expected 95% CL upper limits on the product of cross section and the branching fraction sigma(pp->X)*B(X->HH->gamma gamma b b ) for the nonresonant BSM analysis, performed by changing the parameters $kappa_$lambda, y_t and c_2 while keeping all other parameters fixed at the SM predictions.

Signal efficiencies in the four different signal regions for the nonresonant BSM analysis, performed by changing the parameters $kappa_$lambda, y_t and c_2 while keeping all other parameters fixed at the SM predictions. The four signal regions are made in b-tag and m_HH categries, being those: "Low-purity, High-mass" (LPHM), "Low-purity, Low-mass" (LPLM), "High-purity, High-mass" (HPHM) and "High-purity, Low-mass" (HPLM).


Measurement of the $ \mathrm{ Z } \gamma \rightarrow \nu \bar{\nu} \gamma$ production cross section in pp collisions at $\sqrt{s}=$ 8 TeV and limits on anomalous $ \mathrm{ ZZ } \gamma$ and $ \mathrm{Z} \gamma \gamma$ trilinear gauge boson couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B760 (2016) 448-468, 2016.
Inspire Record 1423069 DOI 10.17182/hepdata.74458

An inclusive measurement of the Zγ→νν‾γ production cross section in pp collisions at s=8TeV is presented, using data corresponding to an integrated luminosity of 19.6 fb −1 collected with the CMS detector at the LHC. This measurement is based on the observation of events with large missing energy and with a single photon with transverse momentum above 145 GeV and absolute pseudorapidity in the range |η|<1.44 . The measured Zγ→νν‾γ production cross section, 52.7±2.1 (stat)±6.4 (syst)±1.4 (lumi) fb , agrees well with the standard model prediction of 50.0−2.2+2.4 fb . A study of the photon transverse momentum spectrum yields the most stringent limits to date on the anomalous ZZγ and Zγγ trilinear gauge boson couplings.

2 data tables

Z gamma -> nu nu gamma production cross section.

One-dimensional 95% CL limits on ZVgamma anomalous trilinear gauge couplings from the Z gamma -> nu nu gamma channel.


Observation of top quark pairs produced in association with a vector boson in pp collisions at $ \sqrt{s}=8 $ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1601 (2016) 096, 2016.
Inspire Record 1396140 DOI 10.17182/hepdata.69486
6 data tables

Expected yields after the final fit, compared to the observed data for OS t$\bar{\mathrm{t}}$Z final states. Here ``hf'' and ``lf'' stand for heavy and light flavors, respectively.

Expected yields after the final fit, compared to the observed data for SS t$\bar{\mathrm{t}}$W final states. The multiboson process includes WWW, WWZ, and W$^{\pm}$W$^{\pm}$; t$\mathrm{\bar{t}}$+X includes t$\mathrm{\bar{t}}\gamma$, t$\mathrm{\bar{t}}\gamma^{*}$, and t$\bar{\mathrm{t}}$WW.

Expected yields after the final fit, compared to the observed data for 3$\ell$ t$\bar{\mathrm{t}}$W and three and 4$\ell$ t$\bar{\mathrm{t}}$Z final states. The 4$\ell$ ``Z-veto'' channel has exactly one lepton pair consistent with a Z boson decay; the ``Z'' channel has two. The multiboson process includes WWW and WWZ; t$\mathrm{\bar{t}}$+X includes t$\mathrm{\bar{t}}\gamma$, t$\mathrm{\bar{t}}\gamma^{*}$, and t$\bar{\mathrm{t}}$WW.

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Search for neutral MSSM Higgs bosons decaying to $\mu^{+} \mu^{-}$ in pp collisions at $ \sqrt{s} =$ 7 and 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B752 (2016) 221-246, 2016.
Inspire Record 1386854 DOI 10.17182/hepdata.70526

A search for neutral Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) for μ+μ− decay channels is presented. The analysis uses data collected by the CMS experiment at the LHC in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.3 fb −1 , respectively. The search is sensitive to Higgs bosons produced either through the gluon fusion process or in association with a bb‾ quark pair. No statistically significant excess is observed in the μ+μ− mass spectrum. Results are interpreted in the framework of several benchmark scenarios, and the data are used to set an upper limit on the MSSM parameter tan⁡β as a function of the mass of the pseudoscalar A boson in the range from 115 to 300 GeV. Model independent upper limits are given for the product of the cross section and branching fraction for gluon fusion and b quark associated production at s=8 TeV . They are the most stringent limits obtained to date in this channel.

3 data tables

The 95% CL upper limit on tan B as a function of mA, after combining the data from the two event categories at the two centre-of-mass energies (7 and 8 TeV). The results are obtained in the framework of the mh-mod+ benchmark scenario.

The 95% CL limit on the product of the cross section and the decay branching fraction to two muons as a function of mPHI, obtained from a model independent analysis of the data. The results refer to b quark associated production, obtained using data collected at swrt(s) = 8 TeV.

The 95% CL limit on the product of the cross section and the decay branching fraction to two muons as a function of mPHI, obtained from a model independent analysis of the data. The results refer to gluon-fusion production, obtained using data collected at swrt(s) = 8 TeV.


Angular analysis of the decay $B^0 \to K^{*0} \mu^+ \mu^-$ from pp collisions at $\sqrt s = 8$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B753 (2016) 424-448, 2016.
Inspire Record 1385600 DOI 10.17182/hepdata.17057
2 data tables

The measured values of signal yield, FL, AFB, and differential branching fraction in bins of the dimuon invariant mass squared. The (FL,AFB) correlation factors are also shown.

The measured values of FL, AFB, and differential branching fraction in bins of the dimuon invariant mass squared, combining the 7 TeV and 8 TeV results.


Comparison of the Z/$\gamma$$^{∗}$ + jets to $\gamma$ + jets cross sections in pp collisions at $ \sqrt{s}=8 $ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1510 (2015) 128, 2015.
Inspire Record 1372730 DOI 10.17182/hepdata.72989

A comparison of the differential cross sections for the processes Z/γ$^{*}$ + jets and photon (γ)+jets is presented. The measurements are based on data collected with the CMS detector at $ \sqrt{s}=8 $ TeV corresponding to an integrated luminosity of 19.7 fb$^{−1}$. The differential cross sections and their ratios are presented as functions of p$_{T}$. The measurements are also shown as functions of the jet multiplicity. Differential cross sections are obtained as functions of the ratio of the Z/γ$^{*}$ p$_{T}$ to the sum of all jet transverse momenta and of the ratio of the Z/γ$^{*}$ p$_{T}$ to the leading jet transverse momentum. The data are corrected for detector effects and are compared to simulations based on several QCD calculations.

14 data tables

The Z boson differential transverse momentum cross-section in an inclusive $Z/\gamma^{*}+\mathrm{jets}$, $N_{\mathrm{jets}} \geq1$ selection.

The $\gamma$ differential transverse momentum cross-section in an inclusive $\gamma+\mathrm{jets}$, $N_{\mathrm{jets}} \geq1$ selection for central rapidities $\vert y_{\gamma} \vert > 1.4$.

The Z boson differential transverse momentum cross-section in an inclusive $Z/\gamma^{*}+\mathrm{jets}$, $N_{\mathrm{jets}} \geq2$ selection.

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Search for the production of dark matter in association with top-quark pairs in the single-lepton final state in proton-proton collisions at sqrt(s) = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1506 (2015) 121, 2015.
Inspire Record 1359293 DOI 10.17182/hepdata.70231

A search is presented for particle dark matter produced in association with a pair of top quarks in pp collisions at a centre-of-mass energy of $ \sqrt{s}=8 $ TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 19.7 fb$^{−1}$. This search requires the presence of one lepton, multiple jets, and large missing transverse energy. No excess of events is found above the SM expectation, and upper limits are derived on the production cross section. Interpreting the findings in the context of a scalar contact interaction between fermionic dark matter particles and top quarks, lower limits on the interaction scale are set. These limits are also interpreted in terms of the dark matter-nucleon scattering cross sections for the spin-independent scalar operator and they complement direct searches for dark matter particles in the low mass region.

4 data tables

Systematic uncertainties from various sources and their impact on the total background prediction.

Expected number of background events in the SR, expected number of signal events for a DM particle with the mass $M_{\chi}$ = 1 GeV, assuming an interaction scale $M_{*}$ = 100 GeV, and observed data. The statistical and systematic uncertainties are given on the expected yields.

Expected number of signal events in SR assuming an interaction scale $M_{*}$ = 100 GeV, signal efficiencies, and observed and expected limits at 90% CL on production cross sections for $\mathrm{pp \rightarrow t\bar{t} + \chi\bar{\chi}}$, for various DM particle masses.

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Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W or Z Bosons

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1510 (2015) 144, 2015.
Inspire Record 1357982 DOI 10.17182/hepdata.70736

A search for a heavy Higgs boson in the $\mathrm{H \to WW}$ and $\mathrm{H \to ZZ}$ decay channels is reported. The search is based upon proton-proton collision data samples corresponding to an integrated luminosity of up to 5.1 fb$^{-1}$ at $\sqrt{s}$ = 7 TeV and up to 19.7 fb$^{-1}$ at $\sqrt{s}$ = 8 TeV, recorded by the CMS experiment at the CERN LHC. Several final states of the $\mathrm{H \to WW}$ and $\mathrm{H \to ZZ}$ decays are analyzed. The combined upper limit at the 95% confidence level on the product of the cross section and branching fraction exclude a Higgs boson with standard model-like couplings and decays in the $m_{\mathrm{H}}$ range from 145 to 1000 GeV. We also interpret the results in the context of an electroweak singlet extension of the standard model.

5 data tables

Upper limits at 95\% CL on the cross section for a heavy Higgs boson decaying to a pair of W bosons as a function of its mass and its width relative to a SM-like Higgs boson.

Upper limits at 95\% CL on the cross section for a heavy Higgs boson decaying to a pair of Z bosons as a function of its mass and its width relative to a SM-like Higgs boson.

Upper limits at 95% CL on the cross section for a heavy Higgs boson as a function of its mass and its width relative to a SM-like Higgs boson. Both, gluon-gluon fusion and VBF production processes are combined, assuming a SM-like ratio between the two.

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Distributions of Topological Observables in Inclusive Three- and Four-Jet Events in pp Collisions at sqrt(s) = 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C75 (2015) 302, 2015.
Inspire Record 1345159 DOI 10.17182/hepdata.75115

This paper presents distributions of topological observables in inclusive three- and four-jet events produced in pp collisions at a centre-of-mass energy of 7 $\,\text {TeV}$ with a data sample collected by the CMS experiment corresponding to a luminosity of 5.1 $\,\text {fb}^{-1}$ . The distributions are corrected for detector effects, and compared with several event generators based on two- and multi-parton matrix elements at leading order. Among the considered calculations, MadGraph interfaced with pythia6 displays the overall best agreement with data.

7 data tables

CORRECTED NORMALIZED DISTRIBUTION OF THREE-JET MASS IN THE INCLUSIVE THREE-JET SAMPLE. THE PROVIDED UNCERTAINTY CORRESPONDS TO SYSTEMATIC UNCERTAINTY.

CORRECTED NORMALIZED DISTRIBUTION OF SCALED ENERGY OF THE LEADING-JET IN THE INCLUSIVE THREE-JET SAMPLE. THE PROVIDED UNCERTAINTY CORRESPONDS TO SYSTEMATIC UNCERTAINTY.

CORRECTED NORMALIZED DISTRIBUTION OF SCALED ENERGY OF THE SECOND-LEADING-JET IN THE INCLUSIVE THREE-JET SAMPLE. THE PROVIDED UNCERTAINTY CORRESPONDS TO SYSTEMATIC UNCERTAINTY.

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Search for resonances and quantum black holes using dijet mass spectra in proton-proton collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D91 (2015) 052009, 2015.
Inspire Record 1340084 DOI 10.17182/hepdata.66764
10 data tables

Inclusive dijet mass spectrum from wide jets (points) compared to a fit (solid curve) and to predictions including detector simulation of multijet events and signal resonances. The predicted multijet shape (QCD MC) has been scaled to the data (see text). The vertical error bars are statistical only and the horizontal error bars are the bin widths. For comparison,the signal distributions for a W resonance of mass 1900 GeV and an excited quark of mass 3.6 TeV are shown. The bin-by-bin fit residuals scaled to the statistical uncertainty of the data , (data - fit)/$\sigma_{data}$, are shown at the bottom and compared with the expected signal contributions.

Observed 95% CL upper limits on $\sigma B A$ for narrow qq, qg, and gg resonances, from the inclusive analysis for signal masses between 1.2 and 5.5 TeV.

Observed 95% CL upper limits on $\sigma B A$ for narrow gg/bb, qq/bb, and bg resonances from the b-enriched analysis, for signal masses between 1.2 and 4.0 TeV. The upper limits are given for different ratios $f_{bb}$ for gg/bb and qq/bb resonances, and for 100% branching fraction into bg.

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Measurement of the inclusive 3-jet production differential cross section in proton–proton collisions at 7 TeV and determination of the strong coupling constant in the TeV range

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C75 (2015) 186, 2015.
Inspire Record 1332746 DOI 10.17182/hepdata.70049

This paper presents a measurement of the inclusive 3-jet production differential cross section at a proton–proton centre-of-mass energy of 7 TeV using data corresponding to an integrated luminosity of 5 $\,\mathrm{fb}^{-1}$ collected with the CMS detector. The analysis is based on the three jets with the highest transverse momenta. The cross section is measured as a function of the invariant mass of the three jets in a range of 445–3270 GeV and in two bins of the maximum rapidity of the jets up to a value of 2. A comparison between the measurement and the prediction from perturbative QCD at next-to-leading order is performed. Within uncertainties, data and theory are in agreement. The sensitivity of the observable to the strong coupling constant $\alpha _\mathrm {S}$ is studied. A fit to all data points with 3-jet masses larger than 664 GeV gives a value of the strong coupling constant of $\alpha _S(M_\mathrm{Z}) = 0.1171 \pm 0.0013\,\text {(exp)} \,^{+0.0073-0.0047}\,\text {(theo)} $ .

6 data tables

Measured 3-jet mass cross section with uncertainties.

Overview of the NP correction factors and their uncertainties in the inner and outer rapidity region.

Determinations of $\alpha_s(M_Z)$ in the considered $m_3$ ranges.

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Measurement of the cross section ratio $\sigma_\mathrm{t \bar{t} b \bar{b}} / \sigma_\mathrm{t \bar{t} jj }$ in pp collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B746 (2015) 132-153, 2015.
Inspire Record 1328962 DOI 10.17182/hepdata.67150
3 data tables

The number of events for each physics process and for each dilepton category after fitting to the data, their total, and the observed total number of events. The results are after the final event selection. The $Z/\gamma^* \to \ell\ell$ uncertainty is from data, while all other uncertainties include only the statistical uncertainties in the MC samples.

Summary of the systematic uncertainties from various sources contributing to $\sigma_{t\bar{t}b\bar{b}}$, $\sigma_{t\bar{t}jj}$, and the ratio $\sigma_{t\bar{t}b\bar{b}/t\bar{t}jj}$ for a jet pt threshold of $p_{\rm T}$ > 20 GeV in the visible phase space.

The measured cross sections $\sigma_{t\bar{t}b\bar{b}}$ and $\sigma_{t\bar{t}jj}$ and their ratio are given for the visible phase space (PS) defined as two leptons with $p_{\rm T}$ > 20 GeV and $|\eta|$ < 2.4 plus four jets, including two b jets with $p_{\rm T}$ > 20 GeV and $|\eta|$ < 2.5, and the full phase space, corrected for acceptance and branching fractions. The full phase-space results are given for jet thresholds of $p_{\rm T}$ > 20 and 40 GeV. The predictions of a NLO theoretical calculation for the full phase space and $p_{\rm T}$ > 40 GeV are also given.


Search for Standard Model Production of Four Top Quarks in the Lepton + Jets Channel in pp Collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1411 (2014) 154, 2014.
Inspire Record 1318946 DOI 10.17182/hepdata.67344

A search is presented for standard model (SM) production of four top quarks $ \left(t\overline{t}t\overline{t}\right) $ in pp collisions in the lepton + jets channel. The data correspond to an integrated luminosity of 19.6 fb$^{−1}$ recorded at a centre-of-mass energy of 8 TeV with the CMS detector at the CERN LHC. The expected cross section for SM $ t\overline{t}t\overline{t} $ production is $ {\sigma}_{t\overline{t}t\overline{t}}^{\mathrm{SM}}\approx 1\,\mathrm{f}\mathrm{b} $ . A combination of kinematic reconstruction and multivariate techniques is used to distinguish between the small signal and large background. The data are consistent with expectations of the SM, and an upper limit of 32 fb is set at a 95% confidence level on the cross section for producing four top quarks in the SM, where a limit of 32 ± 17 fb is expected.

1 data table

Measurement of an upper limit on tttt is set by performing a simultaneous maximum likelihood fit to the distributions in the BDT event discriminant for signal and background in six event categories in the single muon plus jets and single electron plus jets channels.


Search for Displaced Supersymmetry in events with an electron and a muon with large impact parameters

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 114 (2015) 061801, 2015.
Inspire Record 1317640 DOI 10.17182/hepdata.66763

<p>A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at <inline-formula><mml:math display="inline"><mml:mrow><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo>=</mml:mo><mml:mn>8</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:mrow></mml:math></inline-formula>. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>19.7</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mrow><mml:msup><mml:mrow><mml:mi>fb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:mrow></mml:math></inline-formula>. Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>e</mml:mi><mml:mtext>-</mml:mtext><mml:mi>μ</mml:mi></mml:mrow></mml:math></inline-formula> final states. Limits are set on the “displaced supersymmetry” model, with pair production of top squarks decaying into an <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>e</mml:mi><mml:mtext>-</mml:mtext><mml:mi>μ</mml:mi></mml:mrow></mml:math></inline-formula> final state via <inline-formula><mml:math display="inline"><mml:mi>R</mml:mi></mml:math></inline-formula>-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>c</mml:mi><mml:mi>τ</mml:mi><mml:mo>=</mml:mo><mml:mn>2</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>cm</mml:mi></mml:mrow></mml:math></inline-formula>, excluding masses below 790 GeV at 95% confidence level.</p>

8 data tables

Electron transverse impact parameter distribution for data and expected background processes after the preselection requirements have been applied. The event yields per bin have been rescaled to account for the varying bin sizes. The rightmost bin contains the overflow entries.

Muon transverse impact parameter distribution for data and expected background processes after the preselection requirements have been applied. The event yields per bin have been rescaled to account for the varying bin sizes. The rightmost contains the overflow entries.

Numbers of expected and observed events in the three search regions (see the text for the definitions of these regions). Background and signal expectations are quoted as $N_{\text{exp}} \pm 1\sigma$ stat $\pm 1\sigma$ syst. If the estimated background is zero in a particular search region, the estimate is instead taken from the preceding region. Since this should always overestimate the background, we denote this by a preceding "<".

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Search for pair production of third-generation scalar leptoquarks and top squarks in proton–proton collisions at $\sqrt{s}$=8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B739 (2014) 229-249, 2014.
Inspire Record 1309874 DOI 10.17182/hepdata.66933

A search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton-proton collisions corresponding to an integrated luminosity of 19.7 inverse femtobarns, collected with the CMS detector at the LHC with sqrt(s) = 8 TeV. The number of observed events is found to be in agreement with the expected standard model background. Third-generation scalar leptoquarks with masses below 740 GeV are excluded at 95% confidence level, assuming a 100% branching fraction for the leptoquark decay to a tau lepton and a bottom quark. In addition, this mass limit applies directly to top squarks decaying via an R-parity violating coupling lambda'[333]. The search also considers a similar signature from top squarks undergoing a chargino-mediated decay involving the R-parity violating coupling lambda'[3jk]. Each top squark decays to a tau lepton, a bottom quark, and two light quarks. Top squarks in this model with masses below 580 GeV are excluded at 95% confidence level. The constraint on the leptoquark mass is the most stringent to date, and this is the first search for top squarks decaying via lambda'[3jk].

9 data tables

The estimated backgrounds, observed event yields, and expected number of signal events for the leptoquark search. For the simulation-based entries, the statistical and systematic uncertainties are shown separately, in that order.

The estimated backgrounds, observed event yields, and expected number of signal events for the top squark search. For the simulation-based entries, the statistical and systematic uncertainties are shown separately, in that order.

Selection efficiencies in % for the signal in the leptoquark search, estimated from the simulation.

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Search for massive resonances decaying into pairs of boosted bosons in semi-leptonic final states at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1408 (2014) 174, 2014.
Inspire Record 1296080 DOI 10.17182/hepdata.69720

A search for new resonances decaying to WW, ZZ, or WZ is presented. Final states are considered in which one of the vector bosons decays leptonically and the other hadronically. Results are based on data corresponding to an integrated luminosity of 19.7 inverse femtobarns recorded in proton-proton collisions at $\sqrt{s}$ = 8 TeV with the CMS detector at the CERN LHC. Techniques aiming at identifying jet substructures are used to analyze signal events in which the hadronization products from the decay of highly boosted W or Z bosons are contained within a single reconstructed jet. Upper limits on the production of generic WW, ZZ, or WZ resonances are set as a function of the resonance mass and width. We increase the sensitivity of the analysis by statistically combining the results of this search with a complementary study of the all-hadronic final state. Upper limits at 95% confidence level are set on the bulk graviton production cross section in the range from 700 to 10 femtobarns for resonance masses between 600 and 2500 GeV, respectively. These limits on the bulk graviton model are the most stringent to date in the diboson final state.

8 data tables

Observed data distributions as a 1D histogram with statistical errors representing the event yields as a function of the reconstructed M(lnuJ), for the muon high purity channel. The value of mass on the x axis is given for the center of the bin.

Observed data distributions as a 1D histogram with statistical errors representing the event yields as a function of the reconstructed M(lnuJ), for the muon low purity channel. The value of mass on the x axis is given for the center of the bin.

Observed data distributions as a 1D histogram with statistical errors representing the event yields as a function of the reconstructed M(lnuJ), for the electron high purity channel. The value of mass on the x axis is given for the center of the bin.

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Search for massive resonances in dijet systems containing jets tagged as W or Z boson decays in pp collisions at $ \sqrt{s} $ = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1408 (2014) 173, 2014.
Inspire Record 1294937 DOI 10.17182/hepdata.2348

A search is reported for massive resonances decaying into a quark and a vector boson (W or Z), or two vector bosons (WW, WZ, or ZZ). The analysis is performed on an inclusive sample of multijet events corresponding to an integrated luminosity of 19.7 inverse femtobarns, collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. The search uses novel jet-substructure identification techniques that provide sensitivity to the presence of highly boosted vector bosons decaying into a pair of quarks. Exclusion limits are set at a confidence level of 95% on the production of: (i) excited quark resonances q* decaying to qW and qZ for masses less than 3.2 TeV and 2.9 TeV, respectively, (ii) a Randall-Sundrum graviton G[RS] decaying into WW for masses below 1.2 TeV, and (iii) a heavy partner of the W boson W' decaying into WZ for masses less than 1.7 TeV. For the first time mass limits are set on W' to WZ and G[RS] to WW in the all-jets final state. The mass limits on q* to qW, q* to qZ, W' to WZ, G[RS] to WW are the most stringent to date. A model with a "bulk" graviton G[Bulk] that decays into WW or ZZ bosons is also studied.

9 data tables

DATA - Double W/Z tagged events in HIGH purity bin.

BACKGROUND - Double W/Z tagged background in HIGH purity bin estimated from a fit to data.

BACKGROUND PLUS - Double W/Z tagged background variation upward (1 sigma) in HIGH purity bin estimated from a fit to data.

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Evidence of b-Jet Quenching in PbPb Collisions at $\sqrt{s_{NN}}=2.76$  TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 113 (2014) 132301, 2014.
Inspire Record 1269454 DOI 10.17182/hepdata.68931

The production of jets associated to bottom quarks is measured for the first time in PbPb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair. Jet spectra are reported in the transverse momentum (pt) range of 80-250 GeV, and within pseudorapidity abs(eta < 2). The nuclear modification factor (R[AA]) calculated from these spectra shows a strong suppression in the b-jet yield in PbPb collisions relative to the yield observed in pp collisions at the same energy. The suppression persists to the largest values of pt studied, and is centrality dependent. The R[AA] is about 0.4 in the most central events, similar to previous observations for inclusive jets. This implies that jet quenching does not have a strong dependence on parton mass and flavor in the jet pt range studied.

13 data tables

The b-jet yield as a function of pT is for the 0-100% centrality class of PbPb collisions. The yields are scaled by the equivalent number of minimum bias events sampled and by TAA.

The b-jet yield as a function of pT is for the 0-10% centrality class of PbPb collisions. The yields are scaled by the equivalent number of minimum bias events sampled and by TAA.

The b-jet yield as a function of pT is for the 10-30% centrality class of PbPb collisions. The yields are scaled by the equivalent number of minimum bias events sampled and by TAA.

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Search for pair production of excited top quarks in the lepton + jets final state

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1406 (2014) 125, 2014.
Inspire Record 1265512 DOI 10.17182/hepdata.66136

A search is performed for pair-produced spin-3/2 excited top quarks t ∗ t ¯ ∗ , each decaying to a top quark and a gluon. The search uses data collected with the CMS detector from pp collisions at a center-of-mass energy of s = 8 TeV, selecting events that have a single isolated muon or electron, an imbalance in transverse momentum, and at least six jets, of which one must be compatible with originating from the fragmentation of a b quark. The data, corresponding to an integrated luminosity of 19.5 fb(−1), show no significant excess over standard model predictions, and provide a lower limit of 803 GeV at 95% confidence on the mass of the spin-3/2 t(*) quark in an extension of the Randall-Sundrum model, assuming a 100% branching fraction of its decay into a top quark and a gluon. This is the first search for a spin-3/2 excited top quark performed at the LHC.

9 data tables

Kinematic distributions of single l + > 5-jet events in data (points), compared to MC simulation normalized to the number of events observed in data. Shown are pT spectra for muons (a) and electrons (b), and jet spectra for the channels $\mu$+jets (c) and e+jets (d). The reconstructed mtg distribution is shown for the $\mu$+jets channel in (e) and for e+jets in (f).

Kinematic distributions of single l + > 5-jet events in data (points), compared to MC simulation normalized to the number of events observed in data. Shown are pT spectra for muons (a) and electrons (b), and jet spectra for the channels $\mu$+jets (c) and e+jets (d). The reconstructed mtg distribution is shown for the $\mu$+jets channel in (e) and for e+jets in (f).

Kinematic distributions of single l + > 5-jet events in data (points), compared to MC simulation normalized to the number of events observed in data. Shown are pT spectra for muons (a) and electrons (b), and jet spectra for the channels $\mu$+jets (c) and e+jets (d). The reconstructed mtg distribution is shown for the $\mu$+jets channel in (e) and for e+jets in (f).

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Measurement of the top-antitop production cross section in the tau+jets channel in pp collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J. C73 (2013) 2386, 2013.
Inspire Record 1216035 DOI 10.17182/hepdata.62683

The top-quark pair production cross section in 7 TeV center-of-mass energy proton–proton collisions is measured using data collected by the CMS detector at the LHC. The measurement uses events with one jet identified as a hadronically decaying τ lepton and at least four additional energetic jets, at least one of which is identified as coming from a b quark. The analyzed data sample corresponds to an integrated luminosity of 3.9 fb(−1) recorded by a dedicated multijet plus hadronically decaying τ trigger. A neural network has been developed to separate the top-quark pairs from the W+jets and multijet backgrounds. The measured value of is consistent with the standard model predictions.

1 data table

The measured cross section for top-quark pair production.


Measurement of W+W- and ZZ production cross sections in pp collisions at sqrt(s) = 8 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B721 (2013) 190-211, 2013.
Inspire Record 1215317 DOI 10.17182/hepdata.62680

The W^+W^- and ZZ production cross sections are measured in proton-proton collisions at s=8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 fb^-^1. The measurements are performed in the leptonic decay modes W^+W^-->@?^'@n@?^''@n and ZZ->2@?2@?^', where @?=e,@m and @?^'(@?^'')=e,@m,@t. The measured cross sections @s(pp->W^+W^-)=69.9+/-2.8(stat.)+/-5.6(syst.)+/-3.1(lum.) pb and @s(pp->ZZ)=8.4+/-1.0(stat.)+/-0.7(syst.)+/-0.4(lum.) pb, for both Z bosons produced in the mass region 60<m_Z<120 GeV, are consistent with standard model predictions. These are the first measurements of the diboson production cross sections at s=8 TeV.

2 data tables

The measured cross section for W+ W- production performed in the W --> LEPTONPRIME NU mode where LEPTONPRIME is electron, muon or tau.

The measured cross section for Z0Z0 production performed in the Z0 --> LEPTON LEPTONPRIME mode where LEPTON is E or MU and LEPTONPRIME is E, MU or TAU.


Measurement of the sum of $W W$ and $WZ$ production with $W+$dijet events in $pp$ collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J. C73 (2013) 2283, 2013.
Inspire Record 1193935 DOI 10.17182/hepdata.60489

A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at sqrt(s) = 7 TeV with the CMS detector at the LHC, corresponds to an integrated luminosity of 5.0 inverse femtobarns. The measured value of the sum of the inclusive WW and WZ cross sections is sigma(pp to WW+WZ) = 68.9 +/- 8.7 (stat.) +/- 9.7 (syst.) +/- 1.5 (lum.) pb, consistent with the standard model prediction of 65.6 +/- 2.2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes.

1 data table

Integrated cross section for inclusive WW + WZ production from the electron and muon channels combined.