Elliptic flow of charm and strange hadrons in high-multiplicity pPb collisions at $\sqrt{s_{_\mathrm{NN}}} =$ 8.16 TeV

The CMS collaboration Sirunyan, A. M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 121 (2018) 082301, 2018.
Inspire Record 1670168 DOI 10.17182/hepdata.83911

The elliptic azimuthal anisotropy coefficient (v2) is measured for charm (D0) and strange (KS0, Λ, Ξ-, and Ω-) hadrons, using a data sample of p+Pb collisions collected by the CMS experiment, at a nucleon-nucleon center-of-mass energy of sNN=8.16  TeV. A significant positive v2 signal from long-range azimuthal correlations is observed for all particle species in high-multiplicity p+Pb collisions. The measurement represents the first observation of possible long-range collectivity for open heavy flavor hadrons in small systems. The results suggest that charm quarks have a smaller v2 than the lighter quarks, probably reflecting a weaker collective behavior. This effect is not seen in the larger PbPb collision system at sNN=5.02  TeV, also presented.

24 data tables

The elliptic flow, $v_{2}$, for $K^{0}_{S}$ as a function of $p_{T}$ in pPb collision at 8.16 TeV.

The elliptic flow, $v_{2}$, for $\Lambda$ as a function of $p_{T}$ in pPb collision at 8.16 TeV.

The elliptic flow, $v_{2}$, for $\Xi^{-}$ as a function of $p_{T}$ in pPb collision at 8.16 TeV.

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Search for disappearing tracks as a signature of new long-lived particles in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1808 (2018) 016, 2018.
Inspire Record 1669245 DOI 10.17182/hepdata.84707

A search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. A disappearing track is an isolated track with missing hits in the outer layers of the silicon tracker, little or no energy in associated calorimeter deposits, and no associated hits in the muon detectors. This search uses data collected with the CMS detector in 2015 and 2016 from proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, corresponding to an integrated luminosity of 38.4 fb$^{−1}$. The results of the search are interpreted in the context of the anomaly-mediated supersymmetry breaking model. The data are consistent with the background-only hypothesis. Limits are set on the product of the cross section for direct production of charginos and their branching fraction to a neutralino and a pion, as a function of the chargino mass and lifetime. At 95% confidence level, charginos with masses below 715 (695) GeV are excluded for a lifetime of 3 (7) ns, as are charginos with lifetimes from 0.5 to 60 ns for a mass of 505 GeV. These are the most stringent limits using a disappearing track signature on this signal model for chargino lifetimes above ≈0.7 ns.

14 data tables

Predicted signal yields for the 2015 data-taking period, corresponding to $2.7\,\text{fb}^{-1}$, after the application of each of the disappearing track selections for three chargino lifetime hypotheses ($\tau = 0.3$, $3.3$, and $33\,\text{ns}{}$) with a chargino mass of $700\,\text{GeV}{}$. The selections listed are cumulative, i.e., only the events and objects passing a given selection are considered in subsequent selections. The uncertainties shown include only the statistical uncertainty resulting from the limited sizes of the generated samples.

Signal acceptance for each of the generated chargino masses and lifetimes for $\mathrm{p}\mathrm{p} \rightarrow \widetilde{\chi}^\pm_{1} \widetilde{\chi}^\mp_{1}$ events. The denominator for the acceptance is the total number of $\widetilde{\chi}^\pm_{1} \widetilde{\chi}^\mp_{1}$ events generated, with no generator-level filtering, while the numerator is the number of those events that are selected by the disappearing track signal selection, after being processed with the same reconstruction software used on the data. The acceptance corresponds to the 2015 data-taking period. The uncertainties are only the statistical uncertainties resulting from the sizes of the generated samples.

Signal acceptance for each of the generated chargino masses and lifetimes for $\mathrm{p}\mathrm{p} \rightarrow \widetilde{\chi}^\pm_{1} \widetilde{\chi}^\mp_{1}$ events. The denominator for the acceptance is the total number of $\widetilde{\chi}^\pm_{1} \widetilde{\chi}^\mp_{1}$ events generated, with no generator-level filtering, while the numerator is the number of those events that are selected by the disappearing track signal selection, after being processed with the same reconstruction software used on the data. The acceptance corresponds to the 2016A data-taking period. The uncertainties are only the statistical uncertainties resulting from the sizes of the generated samples.

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Observation of $\mathrm{t\overline{t}}$H production

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 120 (2018) 231801, 2018.
Inspire Record 1666824 DOI 10.17182/hepdata.83809

The observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of s=7, 8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9  fb-1, respectively. The data were collected with the CMS detector at the CERN LHC. The results of statistically independent searches for Higgs bosons produced in conjunction with a top quark-antiquark pair and decaying to pairs of W bosons, Z bosons, photons, τ leptons, or bottom quark jets are combined to maximize sensitivity. An excess of events is observed, with a significance of 5.2 standard deviations, over the expectation from the background-only hypothesis. The corresponding expected significance from the standard model for a Higgs boson mass of 125.09 GeV is 4.2 standard deviations. The combined best fit signal strength normalized to the standard model prediction is 1.26-0.26+0.31.

4 data tables

Best fit value of the ttH signal strength modifier $\mu_{\mathrm{ttH}}$, with its 1 and 2 standard deviation confidence intervals ($\sigma$), for the five individual decay channels considered, the combined result for 7+8 TeV alone and for 13 TeV alone, and the overall combined result. The Higgs boson mass is taken to be 125.09 GeV. For the $\mathrm{H}\rightarrow\mathrm{ZZ}$ decay mode, $\mu_{\mathrm{ttH}}$ is constrained to be positive to prevent the corresponding event yield from becoming negative. The SM expectation is shown as a dashed vertical line.

Best fit value, with its uncertainty, of the ttH signal strength modifier $\mu_{\mathrm{ttH}}$, for the five individual decay channels considered, the combined result for 7+8 TeV alone and for 13 TeV alone, and the overall combined result. The total uncertainties are decomposed into their statistical (Stat), experimental systematic (Expt), background theory systematic (Thbgd), and signal theory systematic (Thsig) components.

Distribution of events as a function of the decimal logarithm of S/B, where S and B are the expected post-fit signal (with $\mu_{\mathrm{ttH}}$ = 1) and background yields, respectively, in each bin of the distributions considered in this combination. The shaded histogram shows the expected background distribution. The two hatched histograms, each stacked on top of the background histogram, show the signal expectation for the SM ($\mu_{\mathrm{ttH}}$ = 1) and the observed ($\mu_{\mathrm{ttH}}$ = 1.26) signal strengths.

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Search for a new scalar resonance decaying to a pair of Z bosons in proton-proton collisions at $\sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1806 (2018) 127, 2018.
Inspire Record 1666019 DOI 10.17182/hepdata.83810

A search for a new scalar resonance decaying to a pair of Z bosons is performed in the mass range from 130 GeV to 3 TeV, and for various width scenarios. The analysis is based on proton-proton collisions recorded by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 35.9 fb$^{−1}$ at a center-of-mass energy of 13 TeV. The Z boson pair decays are reconstructed using the 4ℓ, 2ℓ2q, and 2ℓ2ν final states, where ℓ = e or μ. Both gluon fusion and electroweak production of the scalar resonance are considered, with a free parameter describing their relative cross sections. A dedicated categorization of events, based on the kinematic properties of associated jets, and matrix element techniques are employed for an optimal signal and background separation. A description of the interference between signal and background amplitudes for a resonance of an arbitrary width is included. No significant excess of events with respect to the standard model expectation is observed and limits are set on the product of the cross section for a new scalar boson and the branching fraction for its decay to ZZ for a large range of masses and widths.

8 data tables

Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=0 GeV with VBF fraction profiled.

Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=0 GeV in VBF production mode.

Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=10 GeV with VBF fraction profiled.

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Measurement of differential cross sections for the production of top quark pairs and of additional jets in lepton+jets events from pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D97 (2018) 112003, 2018.
Inspire Record 1663958 DOI 10.17182/hepdata.85696

Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at s=13  TeV are measured as a function of kinematic variables of the top quarks and the top quark-antiquark (tt¯) system. In addition, kinematic variables and multiplicities of jets associated with the tt¯ production are measured. This analysis is based on data collected by the CMS experiment at the LHC in 2016 corresponding to an integrated luminosity of 35.8  fb-1. The measurements are performed in the lepton+jets decay channels with a single muon or electron and jets in the final state. The differential cross sections are presented at the particle level, within a phase space close to the experimental acceptance, and at the parton level in the full phase space. The results are compared to several standard model predictions that use different methods and approximations. The kinematic variables of the top quarks and the tt¯ system are reasonably described in general, though none predict all the measured distributions. In particular, the transverse momentum distribution of the top quarks is more steeply falling than predicted. The kinematic distributions and multiplicities of jets are adequately modeled by certain combinations of next-to-leading-order calculations and parton shower models.

239 data tables

Absolute cross section at particle level as a function of $p_\text{T}(\text{t}_\text{h})$.

Covariance matrix of absolute cross section at particle level as a function of $p_\text{T}(\text{t}_\text{h})$.

Absolute cross section at particle level as a function of $|y(\text{t}_\text{h})|$.

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Search for new physics in dijet angular distributions using proton-proton collisions at $\sqrt{s}=$ 13 TeV and constraints on dark matter and other models

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J. C78 (2018) 789, 2018.
Inspire Record 1663452 DOI 10.17182/hepdata.82308

A search is presented for physics beyond the standard model, based on measurements of dijet angular distributions in proton–proton collisions at $\sqrt{s}=13\hbox {TeV}$ . The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 35.9 $\,\text {fb}^{-1}$ . The observed distributions, corrected to particle level, are found to be in agreement with predictions from perturbative quantum chromodynamics that include electroweak corrections. Constraints are placed on models containing quark contact interactions, extra spatial dimensions, quantum black holes, or dark matter, using the detector-level distributions. In a benchmark model where only left-handed quarks participate, contact interactions are excluded at the 95% confidence level up to a scale of 12.8 or 17.5TeV, for destructive or constructive interference, respectively. The most stringent lower limits to date are set on the ultraviolet cutoff in the Arkani–Hamed–Dimopoulos–Dvali model of extra dimensions. In the Giudice–Rattazzi–Wells convention, the cutoff scale is excluded up to 10.1TeV. The production of quantum black holes is excluded for masses below 5.9 and 8.2TeV, depending on the model. For the first time, lower limits between 2.0 and 4.6TeVare set on the mass of a dark matter mediator for (axial-)vector mediators, for the universal quark coupling $g_{\mathrm {\mathrm {q}}} =1.0$ .

34 data tables

Normalized dijet angular distribution for events with dijet mass > 6.0 TeV.

Normalized dijet angular distribution for events with 5.4 < dijet mass < 6.0 TeV.

Normalized dijet angular distribution for events with 4.8 < dijet mass < 5.4 TeV.

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Search for $\mathrm{t}\overline{\mathrm{t}}$H production in the all-jet final state in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2018.
Inspire Record 1663385 DOI 10.17182/hepdata.83685

A search is presented for the associated production of a Higgs boson with a top quark pair in the all-jet final state. Events containing seven or more jets are selected from a sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV collected with the CMS detector at the LHC in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. To separate the $\mathrm{t}\overline{\mathrm{t}}$H signal from the irreducible $\mathrm{t}\overline{\mathrm{t}}+\mathrm{b}\overline{\mathrm{b}}$ background, the analysis assigns leading order matrix element signal and background probability densities to each event. A likelihood-ratio statistic based on these probability densities is used to extract the signal. The results are provided in terms of an observed $\mathrm{t}\overline{\mathrm{t}}$H signal strength relative to the standard model production cross section $\mu=\sigma/\sigma_\mathrm{SM}$, assuming a Higgs boson mass of 125 GeV. The best fit value is $\hat{\mu} =$ 0.9 $\pm$ 0.7 (stat) $\pm$ 1.3 (syst) = 0.9 $\pm$ 1.5 (tot), and the observed and expected upper limits are, respectively, $\mu

2 data tables

Best fit values in the signal strength modifiers (mu), and their 68% CL intervals as split into the statistical and systematic components for each category and combinations of categories.

Values of log10(S/B), where S and B indicate the respective bin-by-bin yields of the signal and background expected in the MEM discriminant distributions, obtained from a combined fit with the constraint in the cross section of mu = 1.


Search for additional neutral MSSM Higgs bosons in the $\tau\tau$ final state in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2018.
Inspire Record 1663234 DOI 10.17182/hepdata.83155

A search is presented for additional neutral Higgs bosons in the $\tau\tau$ final state in proton-proton collisions at the LHC. The search is performed in the context of the minimal supersymmetric extension of the standard model (MSSM), using the data collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes production of the Higgs boson in association with b quarks. No significant deviation above the expected background is observed. Model-independent limits at 95% confidence level (CL) are set on the product of the branching fraction for the decay into $\tau$ leptons and the cross section for the production via gluon fusion or in association with b quarks. These limits range from 18 pb at 90 GeV to 3.5 fb at 3.2 TeV for gluon fusion and from 15 pb (at 90 GeV) to 2.5 fb (at 3.2 TeV) for production in association with b quarks. In the m$_{\text{h}}^{\text{mod+}}$ scenario these limits translate into a 95% CL exclusion of $\tan\beta>$ 6 for neutral Higgs boson masses below 250 GeV, where $\tan\beta$ is the ratio of the vacuum expectation values of the neutral components of the two Higgs doublets. The 95% CL exclusion contour reaches 1.6 TeV for $\tan\beta=$ 60.

6 data tables

Expected and observed 95% CL upper limits for the production of a single narrow resonance, $\phi$, with a mass between 90 GeV and 3.2 TeV via gluon-gluon fusion. This limit database corresponds to the values shown in Figure 7a of the paper.

Expected and observed 95% CL upper limits for the production of a single narrow resonance, $\phi$, with a mass between 90 GeV and 3.2 TeV in association with b-quarks. This limit database corresponds to the values shown in Figure 7b of the paper.

Scan of the likelihood function for the search in the $\tau\tau$ final state for a single narrow resonance, $\phi$, produced via gluon fusion ($gg\phi$) or in association with b quarks ($bb\phi$). The scan is performed in 40000 points of the ($\sigma(gg\phi)\cdot B(\phi\rightarrow\tau\tau)$, $\sigma(bb\phi)\cdot B(\phi\rightarrow\tau\tau)$) plane. An asimov dataset constructed from the expectation of all backgrounds and the SM Higgs boson is tested against a background hypothesis including the SM Higgs boson. For further details and instructions, please have a look into the following README file http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-17-020/2D-likelihood-scans/README.txt. Selected examples of such a likelihood scan are given in Figure 8 of the paper.

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Search for high-mass resonances in dilepton final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1806 (2018) 120, 2018.
Inspire Record 1662926 DOI 10.17182/hepdata.83971

A search is presented for new high-mass resonances decaying into electron or muon pairs. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 36 fb$^{−1}$. Observations are in agreement with standard model expectations. Upper limits on the product of a new resonance production cross section and branching fraction to dileptons are calculated in a model-independent manner. This permits the interpretation of the limits in models predicting a narrow dielectron or dimuon resonance. A scan of different intrinsic width hypotheses is performed. Limits are set on the masses of various hypothetical particles. For the $ {Z}_{\mathrm{SSM}}^{\prime}\left({Z}_{{}^{\psi}}^{\prime}\right) $ particle, which arises in the sequential standard model (superstring-inspired model), a lower mass limit of 4.50 (3.90) TeV is set at 95% confidence level. The lightest Kaluza-Klein graviton arising in the Randall-Sundrum model of extra dimensions, with coupling parameters k/M$_{Pl}$ of 0.01, 0.05, and 0.10, is excluded at 95% confidence level below 2.10, 3.65, and 4.25 TeV, respectively. In a simplified model of dark matter production via a vector or axial vector mediator, limits at 95% confidence level are obtained on the masses of the dark matter particle and its mediator.

23 data tables

The observed upper limits at 95% CL on the product of production cross section and branching fraction for a spin-1 resonance with a width equal to 0.6% of the resonance mass, relative to the product of production cross section and branching fraction of a Z boson.

The expected upper limits together with the 68 and 95% quantiles at 95% CL on the product of production cross section and branching fraction for a spin-1 resonance with a width equal to 0.6% of the resonance mass, relative to the product of production cross section and branching fraction of a Z boson.

The observed upper limits at 95% CL on the product of production cross section and branching fraction for a spin-1 resonance, for widths equal to 0.6, 3, 5, and 10% of the resonance mass, relative to the product of production cross section and branching fraction for a Z boson.

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Evidence for associated production of a Higgs boson with a top quark pair in final states with electrons, muons, and hadronically decaying $\tau$ leptons at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1808 (2018) 066, 2018.
Inspire Record 1662661 DOI 10.17182/hepdata.84635

Results of a search for the standard model Higgs boson produced in association with a top quark pair ($\mathrm{t\overline{t}}$H) in final states with electrons, muons, and hadronically decaying $\tau$ leptons are presented. The analyzed data set corresponds to an integrated luminosity of 35.9 fb$^{-1}$ recorded in proton-proton collisions at $\sqrt{s} =$ 13 TeV by the CMS experiment in 2016. The sensitivity of the search is improved by using matrix element and machine learning methods to separate the signal from backgrounds. The measured signal rate amounts to 1.23 $^{+0.45}_{-0.43}$ times the production rate expected in the standard model, with an observed (expected) significance of 3.2$\sigma$ (2.8$\sigma$), which represents evidence for $\mathrm{t\overline{t}}$H production in those final states. An upper limit on the signal rate of 2.1 times the standard model production rate is set at 95% confidence level.

1 data table

Signal rates $\mu$, in units of the SM $\mathrm{t\overline(t}H}$ production rate, measured in each of the categories individually and for the combination of all six categories. The blue (green) band corresponds to the statistical (total) uncertainty on the combined signal rate.


Measurement of the $\Lambda_b$ polarization and angular parameters in $\Lambda_b\to J/\psi\, \Lambda$ decays from pp collisions at $\sqrt{s}=$ 7 and 8 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D97 (2018) 072010, 2018.
Inspire Record 1654926 DOI 10.17182/hepdata.83664

An analysis of the bottom baryon decay Λb→J/ψ(→μ+μ-)Λ(→pπ-) is performed to measure the Λb polarization and three angular parameters in data from pp collisions at s=7 and 8 TeV, collected by the CMS experiment at the Large Hadron Collider. The Λb polarization is measured to be 0.00±0.06(stat)±0.06(syst) and the parity-violating asymmetry parameter is determined to be 0.14±0.14(stat)±0.10(syst). The measurements are compared to various theoretical predictions, including those from perturbative quantum chromodynamics.

3 data tables

The measured values of the angular parameters and the $\Lambda_b$ polarization.

The values of the helicity amplitudes in the decay.

Correlation matrix for the fitted parameters.


Measurement of the inelastic proton-proton cross section at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1807 (2018) 161, 2018.
Inspire Record 1653948 DOI 10.17182/hepdata.83970

A measurement of the inelastic proton-proton cross section with the CMS detector at a center-of-mass energy of $\sqrt{s} =$ 13 TeV is presented. The analysis is based on events with energy deposits in the forward calorimeters, which cover pseudorapidities of -6.6 $< \eta <$ -3.0 and +3.0 $< \eta <$ +5.2. An inelastic cross section of 68.6 $\pm$ 0.5 (syst) $\pm$ 1.6 (lumi) mb is obtained for events with $M_\mathrm{X} >$ 4.1 GeV and/or $M_\mathrm{Y} >$ 13 GeV, where $M_\mathrm{X}$ and $M_\mathrm{Y}$ are the masses of the diffractive dissociation systems at negative and positive pseudorapidities, respectively. The results are compared with those from other experiments as well as to predictions from high-energy hadron-hadron interaction models.

1 data table

The measured fiducial cross sections. The first bin represents the $\xi > 10^{-6}$ region, while the second bin represents the extended $\xi_{X} > 10^{-7}$ or $\xi_{Y} > 10^{-6}$ result. The first uncertainty is the systematic uncertainty excluding luminosity, the second is the luminosity uncertainty.


Search for lepton-flavor violating decays of heavy resonances and quantum black holes to eμ final states in proton-proton collisions at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1804 (2018) 073, 2018.
Inspire Record 1653123 DOI 10.17182/hepdata.86568

A search is reported for heavy resonances decaying into e$\mu$ final states in proton-proton collisions recorded by the CMS experiment at the CERN LHC at $\sqrt{s}=$ 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The search focuses on resonance masses above 200 GeV. With no evidence found for physics beyond the standard model in the e$\mu$ mass spectrum, upper limits are set at 95% confidence level on the product of the cross section and branching fraction for this lepton-flavor violating signal. Based on these results, resonant $\tau$ sneutrino production in R-parity violating supersymmetric models is excluded for masses below 1.7 TeV, for couplings $\lambda_{132} = \lambda_{231} = \lambda'_{311} = 0.01$. Heavy Z$'$ gauge bosons with lepton-flavor violating transitions are excluded for masses up to 4.4 TeV. The e$\mu$ mass spectrum is also interpreted in terms of non-resonant contributions from quantum black-hole production in models with one to six extra spatial dimensions, and lower mass limits are found between 3.6 and 5.6 TeV. In all interpretations used in this analysis, the results of this search improve previous limits by about 1 TeV. These limits correspond to the most sensitive values obtained at colliders.

7 data tables

Cross section of QBH as a function of mass. The cross section includes the branching ratio of QBH decaying to $e\mu$.

Cross section of RPV tau-sneutrino as a function of mass. Cross section includes the branching ratio of tau-sneutrino decaying to $e\mu$.

Cross section of Z' as a function of mass. The cross sections include branching ratio $BR(Z' -> e \mu) = 10\%$

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Comparing transverse momentum balance of b jet pairs in pp and PbPb collisions at $ \sqrt{s_{\mathrm{NN}}}=5.02 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1803 (2018) 181, 2018.
Inspire Record 1652833 DOI 10.17182/hepdata.82819

The transverse momentum balance of pairs of back-to-back b quark jets in PbPb and pp collisions recorded with the CMS detector at the LHC is reported. The center-of-mass energy in both collision systems is 5.02 TeV per nucleon pair. Compared to the pp collision baseline, b quark jets have a larger imbalance in the most central PbPb collisions, as expected from the jet quenching effect. The data are also compared to the corresponding measurement with inclusive dijets. In the most central collisions, the imbalance of b quark dijets is comparable to that of inclusive dijets.

14 data tables

Performance of double b-jet tagging, in terms of b-tagging purity and efficiency

Delta phi distributions of incluisve dijets and b-quark dijets in pp collisions

Delta phi distributions of incluisve dijets and b-quark dijets in central (0-10%) PbPb collisions

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Observation of medium induced modifications of jet fragmentation in PbPb collisions using isolated-photon-tagged jets

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2018.
Inspire Record 1648162 DOI 10.17182/hepdata.80817

Measurements of fragmentation functions for jets associated with an isolated photon are presented for the first time in pp and PbPb collisions. The analysis uses data collected with the CMS detector at the CERN LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Fragmentation functions are obtained for jets with p$_\mathrm{T}^\text{jet} >$ 30 GeV in events containing an isolated photon with p$_\mathrm{T}^\gamma>$ 60 GeV, using charged tracks with transverse momentum p$_\mathrm{T}^\text{trk} >$ 1 GeV in a cone around the jet axis. The association with an isolated photon constrains the initial p$_\mathrm{T}$ and azimuthal angle of the parton whose shower produced the jet. For central PbPb collisions, modifications of the jet fragmentation functions are observed when compared to those measured in pp collisions, while no significant differences are found in the 50% most peripheral collisions. Jets in central PbPb events show an excess (depletion) of low (high) p$_\mathrm{T}$ particles, with a transition around 3 GeV.

16 data tables

$\xi^\mathrm{jet}$ distributions for jets associated with an isolated photon in pp and 50-100% centrality PbPb collisions. The resolutions of the measured jet energy and azimuthal angle in pp are smeared to match those in the PbPb sample.

$\xi^\mathrm{jet}$ distributions for jets associated with an isolated photon in pp and 30-50% centrality PbPb collisions. The resolutions of the measured jet energy and azimuthal angle in pp are smeared to match those in the PbPb sample.

$\xi^\mathrm{jet}$ distributions for jets associated with an isolated photon in pp and 10-30% centrality PbPb collisions. The resolutions of the measured jet energy and azimuthal angle in pp are smeared to match those in the PbPb sample.

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Search for decays of stopped exotic long-lived particles produced in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP, 2017.
Inspire Record 1645630 DOI 10.17182/hepdata.83010

A search is presented for the decays of heavy exotic long-lived particles (LLPs) that are produced in proton-proton collisions at a center-of-mass energy of 13\TeV at the CERN LHC and come to rest in the CMS detector. Their decays would be visible during periods of time well separated from proton-proton collisions. Two decay scenarios of stopped LLPs are explored: a hadronic decay detected in the calorimeter and a decay into muons detected in the muon system. The calorimeter (muon) search covers a period of sensitivity totaling 721 (744) hours in 38.6 (39.0) fb$^{-1}$ of data collected by the CMS detector in 2015 and 2016. The results are interpreted in several scenarios that predict LLPs. Production cross section limits are set as a function of the mean proper lifetime and the mass of the LLPs, for lifetimes between 100 ns and 10 days. These are the most stringent limits to date on the mass of hadronically decaying stopped LLPs, and this is the first search at the LHC for stopped LLPs that decay to muons.

33 data tables

The $\Delta t_{\text{DT}}$ distribution for 2016 data, MC simulated cosmic ray muon, 1000 GeV gluino signal, and 600 GeV MCHAMP signal events, for the muon search. The events plotted pass a subset of the full analysis selection that is designed to select good-quality DSA muon tracks but does not reject the cosmic ray muon background. The number of cosmic ray muon background events is greatly reduced when the full selection is applied, as we require $\Delta t_{\text{DT}}>-20$ ns and $\Delta t_{\text{RPC}}>-7.5$ ns. The histograms are normalized to unit area.

The $\Delta t_{\text{RPC}}$ distribution for 2016 data, MC simulated cosmic ray muon, 1000 GeV gluino signal, and 600 GeV MCHAMP signal events, for the muon search. The events plotted pass a subset of the full analysis selection that is designed to select good-quality DSA muon tracks but does not reject the cosmic ray muon background. The number of cosmic ray muon background events is greatly reduced when the full selection is applied, as we require $\Delta t_{\text{DT}}>-20$ ns and $\Delta t_{\text{RPC}}>-7.5$ ns. The histograms are normalized to unit area.

The $\varepsilon_{\text{reco}}$ values as a function of $E_{g}$, for $\tilde{g}$ R-hadrons that stop in the EB or HB, in the MC simulation, for the calorimeter search. The $\varepsilon_{\text{reco}}$ values are plotted for the two-body gluino decay, when $m_{\tilde{g}}$ is 600 GeV.

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Measurement of prompt and nonprompt charmonium suppression in PbPb collisions at 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1644903 DOI 10.17182/hepdata.80816

The nuclear modification factors of J/$\psi$ and $\psi$(2S) mesons are measured in PbPb collisions at a centre-of-mass energy per nucleon pair of $\sqrt{s_{\mathrm{NN}}} =$ 5.02 TeV. The analysis is based on PbPb and pp data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464 $\mu$b$^{-1}$ and 28 pb$^{-1}$, respectively. The measurements are performed in the dimuon rapidity range of $|y| <$ 2.4 as a function of centrality, rapidity, and transverse momentum (p$_\mathrm{T}$) from p$_\mathrm{T}=$ 3 GeV/$c$ in the most forward region and up to 50 GeV/$c$. Both prompt and nonprompt (coming from b hadron decays) mesons are observed to be increasingly suppressed with centrality, with a magnitude similar to the one observed at $\sqrt{s_{\mathrm{NN}}}=$ 2.76 TeV for the two J/$\psi$ meson components. No dependence on rapidity is observed for either prompt or nonprompt J/$\psi$ mesons. An indication of a lower prompt J/$\psi$ meson suppression at high p$_\mathrm{T}$ is seen with respect to that observed at intermediate p$_\mathrm{T}$. The prompt $\psi$(2S) meson yield is found to be more suppressed than that of the prompt J/$\psi$ mesons in the entire p$_\mathrm{T}$ range.

32 data tables

Fraction of J/psi mesons coming from the decay of b hadrons, i.e. nonprompt J/psi meson fraction, as a function of dimuon pT for pp and PbPb collisions, for all centralities.

Fraction of J/psi mesons coming from the decay of b hadrons, i.e. nonprompt J/psi meson fraction, as a function of dimuon rapidity for pp and PbPb collisions, for all centralities.

Differential cross section of prompt J/psi mesons as a function of dimuon pT in pp and PbPb collisions. The PbPb cross sections are normalised by TAA for direct comparison. Global uncertainties arise from the integrated luminosity uncertainty in pp collisions, and the number of minimum bias events and TAA uncertainties for PbPb collisions.

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Search for $R$-parity violating supersymmetry in pp collisions at $\sqrt{s} = $ 13 TeV using b jets in a final state with a single lepton, many jets, and high sum of large-radius jet masses

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett. B783 (2018) 114-139, 2018.
Inspire Record 1644901 DOI 10.17182/hepdata.81002

Results are reported from a search for physics beyond the standard model in proton–proton collisions at a center-of-mass energy of s=13TeV . The search uses a signature of a single lepton, large jet and bottom quark jet multiplicities, and high sum of large-radius jet masses, without any requirement on the missing transverse momentum in an event. The data sample corresponds to an integrated luminosity of 35.9 fb −1 recorded by the CMS experiment at the LHC. No significant excess beyond the prediction from standard model processes is observed. The results are interpreted in terms of upper limits on the production cross section for R -parity violating supersymmetric extensions of the standard model using a benchmark model of gluino pair production, in which each gluino decays promptly via g˜→tbs . Gluinos with a mass below 1610 GeV are excluded at 95% confidence level.

5 data tables

Table 1. Post-fit yields for the background-only fit, observed data, and expected yields for mgluino = 1600 GeV in each search bin.

Figure 8. Observed cross section upper limits at 95% CL for a model of gluino pair production with gluino->tbs compared to the gluino pair production cross section.

Figure 8. Expected limits at 95% CL and their ±1 sigma variations for a model of gluino pair production with gluino->tbs compared to the gluino pair production cross section.

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Search for lepton flavour violating decays of the Higgs boson to $\mu\tau$ and e$\tau$ in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1806 (2018) 001, 2018.
Inspire Record 1644363 DOI 10.17182/hepdata.83881

A search for lepton flavour violating decays of the Higgs boson in the μτ and eτ decay modes is presented. The search is based on a data set corresponding to an integrated luminosity of 35.9 fb$^{−1}$ of proton-proton collisions collected with the CMS detector in 2016, at a centre-of-mass energy of 13 TeV. No significant excess over the standard model expectation is observed. The observed (expected) upper limits on the lepton flavour violating branching fractions of the Higgs boson are ℬ(H → μτ) < 0.25% (0.25%) and ℬ(H → eτ) < 0.61% (0.37%), at 95% confidence level. These results are used to derive upper limits on the off-diagonal μτ and eτ Yukawa couplings $ \sqrt{{\left|{Y}_{\mu \tau}\right|}^2+{\left|{Y}_{\tau \mu}\right|}^2}<1.43\times {10}^{-3} $ and $ \sqrt{{\left|{Y}_{\mathrm{e}\tau}\right|}^2+{\left|{Y}_{\tau \mathrm{e}}\right|}^2}<2.26\times {10}^{-3} $ at 95% confidence level. The limits on the lepton flavour violating branching fractions of the Higgs boson and on the associated Yukawa couplings are the most stringent to date.

6 data tables

Expected and observed 95 percent CL upper limits on BR(H to mu tau) for each individual category and combined from BDT fit analysis

Expected and observed 95 percent CL upper limits on BR(H to mu tau) for each individual category and combined from collinear mass fit analysis

Expected and observed 95 percent CL upper limits on BR(H to e tau) for each individual category and combined from BDT fit analysis

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Study of jet quenching with isolated-photon+jet correlations in PbPb and pp collisions at $\sqrt{s_{_{\mathrm{NN}}}} =$ 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1638996 DOI 10.17182/hepdata.80815

Measurements of azimuthal angle and transverse momentum ($p_\mathrm{T}$) correlations of isolated photons and associated jets are reported for pp and PbPb collisions at $\sqrt{s_{_{\mathrm{NN}}}} =$ 5.02 TeV. The data were recorded with the CMS detector at the CERN LHC. For events containing a leading isolated photon with $p_\mathrm{T}^\gamma >$ 40 GeV$/c$ and an associated jet with $p_\mathrm{T}^\text{jet} >$ 30 GeV$/c$, the photon+jet azimuthal correlation and \pt imbalance in PbPb collisions are studied as functions of collision centrality and $p_\mathrm{T}^\gamma$. The results are compared to pp reference data collected at the same collision energy and to predictions from several theoretical models for parton energy loss. No evidence of broadening of the photon+jet azimuthal correlations is observed, while the ratio $p_\mathrm{T}^\text{jet}/p_\mathrm{T}^\gamma$ decreases significantly for PbPb data relative to the pp reference. All models considered agree within uncertainties with the data. The number of associated jets per photon with $p_\mathrm{T}^\gamma >$ 80 GeV$/c$ is observed to be shifted towards lower $p_\mathrm{T}^\text{jet}$ values in central PbPb collisions compared to pp collisions.

7 data tables

Jet resolution parameters for pp and PbPb collisions in various centrality bins.

The azimuthal correlation of photons and jets in five $p_{\mathrm{T}}^{\gamma}$ intervals for 0-30% and 30-100% centrality PbPb collisions. The smeared pp data are included for comparison.

Distribution of $x_{\mathrm{j}\gamma} = p_{\mathrm{T}}^{\mathrm{jet}} / p_{\mathrm{T}}^{\gamma}$ in five $p_{\mathrm{T}}^{\gamma}$ intervals for 0-30% and 30-100% centrality PbPb collisions. The smeared pp data are included for comparison. Empty bins are denoted as 'empty' in the table.

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Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1636197 DOI 10.17182/hepdata.80151

Event-by-event fluctuations in the elliptic-flow coefficient $v_2$ are studied in PbPb collisions at $\sqrt{s_{_\text{NN}}} = 5.02$ TeV using the CMS detector at the CERN LHC. Elliptic-flow probability distributions ${p}(v_2)$ for charged particles with transverse momentum 0.3$< p_\mathrm{T} <$3.0 GeV and pseudorapidity $| \eta | <$ 1.0 are determined for different collision centrality classes. The moments of the ${p}(v_2)$ distributions are used to calculate the $v_{2}$ coefficients based on cumulant orders 2, 4, 6, and 8. A rank ordering of the higher-order cumulant results and nonzero standardized skewness values obtained for the ${p}(v_2)$ distributions indicate non-Gaussian initial-state fluctuation behavior. Bessel-Gaussian and elliptic power fits to the flow distributions are studied to characterize the initial-state spatial anisotropy.

14 data tables

Unfolded elliptic flow probability density (p(v_2)) for 15-20\% collision centralities

Unfolded elliptic flow probability density (p(v_2)) for 30-35\% collision centralities

Unfolded elliptic flow probability density (p(v_2)) for 55-60\% collision centralities

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Measurement of the underlying event activity in inclusive Z boson production in proton-proton collisions at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, A.M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1807 (2018) 032, 2018.
Inspire Record 1635889 DOI 10.17182/hepdata.80167

This paper presents a measurement of the underlying event activity in proton-proton collisions at a center-of-mass energy of 13 TeV, performed using inclusive Z boson production events collected with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 2.1 fb$^{−1}$. The underlying event activity is quantified in terms of the charged particle multiplicity, as well as of the scalar sum of the charged particles’ transverse momenta in different topological regions defined with respect to the Z boson direction. The distributions are unfolded to the stable particle level and compared with predictions from various Monte Carlo event generators, as well as with similar CDF and CMS measurements at center-of-mass energies of 1.96 and 7 TeV respectively.

6 data tables

Unfolded distributions of particle density in Z events, as a function of $p_{T}^{\mu\mu}$ in the towards ($\Delta\phi< 60^{\circ}$) region. Error bars represent the statistical and systematic uncertainties added in quadrature.

Unfolded distributions of particle density in Z events, as a function of $p_{T}^{\mu\mu}$ in the transverse ($60^{\circ} <\Delta\phi< 120^{\circ}$) region. Error bars represent the statistical and systematic uncertainties added in quadrature.

Unfolded distributions of particle density in Z events, as a function of $p_{T}^{\mu\mu}$ in the away ($\Delta\phi> 120^{\circ}$) region. Error bars represent the statistical and systematic uncertainties added in quadrature.

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Measurement of the inclusive $\mathrm{t}\overline{\mathrm{t}}$ cross section in pp collisions at $\sqrt{s} =$ 5.02 TeV using final states with at least one charged lepton

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1635271 DOI 10.17182/hepdata.81690

The top quark pair production cross section ($\sigma_{\mathrm{t}\overline{\mathrm{t}}}$) is measured for the first time in pp collisions at a center-of-mass energy of 5.02 = TeV. The data were collected by the CMS experiment at the LHC and correspond to an integrated luminosity of 27.4 pb$^{-1}$. The measurement is performed by analyzing events with at least one charged lepton. The measured cross section is $ \sigma_{\mathrm{t}\overline{\mathrm{t}}} = 69.5 \pm 6.1$ (stat) $\pm 5.6$ (syst) $\pm 1.6$ (lumi) pb, with a total relative uncertainty of 12%. The result is in agreement with the expectation from the standard model. The impact of the presented measurement on the determination of the gluon distribution function is investigated.

15 data tables

The measured fiducial cross sections in the $\ell$+jets and dilepton ($\rm{e}^\pm \mu^\mp$ or $\mu^\pm \mu^\mp$) decay channels. The first uncertainty is the statistical, the second is the systematic, and the last due to the integrated luminosity.

The measured total cross sections based on the $\ell$+jets (left), $\rm{e}^\pm \mu^\mp$ (middle) and $\mu^\pm \mu^\mp$ (right) decay channels. The first uncertainty is the statistical, the second is the systematic, and the last due to the integrated luminosity.

The measured total cross section in the combined $\ell$+jets and dilepton ($\rm{e}^\pm \mu^\mp$ or $\mu^\pm \mu^\mp$) decay channels. The weights of the individual measurements are 81.8% for $\ell$+jets, 13.5% for $\rm{e}^\pm \mu^\mp$, and 4.7% for $\mu^\pm \mu^\mp$ channels. The first uncertainty is the statistical, the second is the systematic, and the last due to the integrated luminosity.

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Search for top squarks and dark matter particles in opposite-charge dilepton final states at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D97 (2018) 032009, 2018.
Inspire Record 1634253 DOI 10.17182/hepdata.79809

A search for new physics is presented in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from b quarks, and missing transverse momentum (pTmiss). The search uses proton-proton collision data at s=13  TeV amounting to 35.9  fb-1 of integrated luminosity collected using the CMS detector in 2016. Hypothetical signal events are efficiently separated from the dominant tt¯ background with requirements on pTmiss and transverse-mass variables. No significant deviation is observed from the expected background. Exclusion limits are set in the context of simplified supersymmetric models with pair-produced top squarks. For top squarks, decaying exclusively to a top quark and a neutralino, exclusion limits are placed at 95% confidence level on the mass of the lightest top squark up to 800 GeV and on the lightest neutralino up to 360 GeV. These results, combined with searches in the single-lepton and all-jet final states, raise the exclusion limits up to 1050 GeV for the lightest top squark and up to 500 GeV for the lightest neutralino. For top squarks undergoing a cascade decay through charginos and sleptons, the mass limits reach up to 1300 GeV for top squarks and up to 800 GeV for the lightest neutralino. The results are also interpreted in a simplified model with a dark matter (DM) particle coupled to the top quark through a scalar or pseudoscalar mediator. For light DM, mediator masses up to 100 (50) GeV are excluded for scalar (pseudoscalar) mediators. The result for the scalar mediator achieves some of the most stringent limits to date in this model.

49 data tables

Additional Figure 3. Observed limits for the T2tt model in the top squark - LSP mass plane using aggregate signal regions. The numbers indicate the 95% CL upper limit on the cross section times the square of the branching fraction at each point of the plane.

Additional Figure 3. Observed exclusion region at 95% CL assuming 100% branching fraction.

Additional Figure 3. Expected exclusion region at 95% CL assuming 100% branching fraction.

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Search for new physics in events with a leptonically decaying Z boson and a large transverse momentum imbalance in proton–proton collisions at $\sqrt{s} $ = 13 $\,\text {TeV}$

The CMS collaboration Sirunyan, A.M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J. C78 (2018) 291, 2018.
Inspire Record 1633763 DOI 10.17182/hepdata.82304

A search for new physics in events with a Z boson produced in association with large missing transverse momentum at the LHC is presented. The search is based on the 2016 data sample of proton-proton collisions recorded with the CMS experiment at $\sqrt{s} = $ 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The results of this search are interpreted in terms of a simplified model of dark matter production via spin-0 or spin-1 mediators, a scenario with a standard-model-like Higgs boson produced in association with the Z boson and decaying invisibly, a model of unparticle production, and a model with large extra spatial dimensions. No significant deviations from the background expectations are found, and limits are set on relevant model parameters, significantly extending the results previously achieved in this channel.

9 data tables

The 95% CL lower limits on the reduced Planck mass $M_{D}$ as a function of the number of extra dimensions $d$.

The covariance matrix of the bin contents of the background fit. Because the matrix is symmetric by definiton, only the upper half is provided here for presentational purposes. The full matrix can be obtained by mirroring the given half along the diagonal.

Limit on the signal strength of the DM signal in a simplified model with an axial-vector mediator.

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