Search for high mass dijet resonances with a new background prediction method in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1764471 DOI 10.17182/hepdata.91059

A search for narrow and broad resonances with masses greater than 1.8 TeV decaying to a pair of jets is presented. The search uses proton-proton collision data at $\sqrt{s}=$13 TeV collected at the LHC, corresponding to an integrated luminosity of 137 fb$^{-1}$. The background arising from standard model processes is predicted with the fit method used in previous publications and with a new method. The dijet invariant mass spectrum is well described by both data-driven methods, and no significant evidence for the production of new particles is observed. Model independent upper limits are reported on the production cross sections of narrow resonances, and broad resonances with widths up to 55% of the resonance mass. Limits are presented on the masses of narrow resonances from various models: string resonances, scalar diquarks, axigluons, colorons, excited quarks, color-octet scalars, W' and Z' bosons, Randall-Sundrum gravitons, and dark matter mediators. The limits on narrow resonances are improved by 200 to 800 GeV relative to those reported in previous CMS dijet resonance searches. The limits on dark matter mediators are presented as a function of the resonance mass and width, and on the associated coupling strength as a function of the mediator mass. These limits exclude at 95% confidence level a dark matter mediator with a mass of 1.8 TeV and width 1% of its mass or higher, up to one with a mass of 4.8 TeV and a width 45% of its mass or higher.

10 data tables

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for spin-1 resonances produced and decaying in the quark-quark channel, shown for various values of intrinsic width as a function of resonance mass.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for spin-2 resonances produced and decaying in the quark-quark channel, shown for various values of intrinsic width as a function of resonance mass.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for spin-2 resonances produced and decaying in the gluon-gluon channel, shown for various values of intrinsic width as a function of resonance mass.

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Search for new neutral Higgs bosons through the H$\to$ ZA $\to \ell^{+}\ell^{-} \mathrm{b\bar{b}}$ process in pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1764795 DOI 10.17182/hepdata.90710

This paper reports on a search for an extended scalar sector of the standard model, where a new CP-even (odd) boson decays to a Z boson and a lighter CP-odd (even) boson, and the latter further decays to a b quark pair. The Z boson is reconstructed via its decays to electron or muon pairs. The analysed data were recorded in proton-proton collisions at a center-of-mass energy $\sqrt{s} = $ 13 TeV, collected by the CMS experiment at the LHC during 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Data and predictions from the standard model are in agreement within the uncertainties. Upper limits at 95% confidence level are set on the production cross section times branching fraction, with masses of the new bosons up to 1000 GeV. The results are interpreted in the context of the two-Higgs-doublet model.

10 data tables

Expected and observed 95% CL upper limits on the product of the production cross section and branching fraction for H(A) -> ZA(H) -> bbbar as a function of mA and mH. The limits are computed using the asymptotic CLs method, combining the ee and μμ channels.

Expected and observed 95% CL upper limits on the signal strength for the Type-II 2HDM benchmark (tan(beta)=1.5, cos(beta-alpha)=0.01) as a function of mA and mH . The limits are computed using the asymptotic CLs method, combining the ee and μμ channels.

Expected and observed 95% CL upper limits on the signal strength for the Type-II 2HDM benchmark (mH = 379 GeV and m A = 172 GeV) as a function of tan(beta) and cos(beta-alpha). The limits are computed using the asymptotic CLs method, combining the ee and μμ channels.

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Search for dijet resonances using events with three jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1764796 DOI 10.17182/hepdata.91058

A search for a narrow resonance with a mass between 350 and 700 GeV, and decaying into a pair of jets, is performed using proton-proton collision events containing at least three jets. The data sample corresponds to an integrated luminosity of 18.3 fb$^{-1}$ recorded at $\sqrt{s}=$ 13 TeV with the CMS detector. Data are collected with a technique known as "data scouting", in which the events are reconstructed, selected, and recorded at a high rate in a compact form by the high-level trigger. The three-jet final state provides sensitivity to lower resonance masses than in previous searches using the data scouting technique. The spectrum of the dijet invariant mass, calculated from the two jets with the largest transverse momenta in the event, is used to search for a resonance. No significant excess over a smoothly falling background is found. Limits at 95% confidence level are set on the production cross section of a narrow dijet resonance. The corresponding upper limits on the coupling of a narrow vector resonance interacting only with quarks are between 0.10 and 0.15, depending on the resonance mass. These results represent the most stringent upper limits in the mass range between 350 and 450 GeV obtained with a search that is sensitive to the decay of the resonance into light-flavor quarks.

6 data tables

Dijet mass spectrum (points) compared to a fitted parameterization of the background (solid curve), where the fit is performed in the range 290 < $m_{jj}$ < 1000 GeV in the background-only hypothesis. The horizontal bars show the widths of each bin in dijet mass. The dashed lines represent the dijet mass distribution from 400, 550, and 700 GeV resonance signals expected to be excluded at 95% CL by this analysis.

Acceptance for a vector resonance decaying into a dijet as a function of the resonance mass. The acceptance is calculated using signal simulations for the analysis selection, namely three wide jets with $p_{\mathrm{T}}$ > 72 GeV and |$\eta$| < 2.5, and |$\eta_{1}$ − $\eta_{2}$|<1.1. The errors are dominated by the uncertainties in the parton shower modeling used in signal simulations.

Comparison of the dijet mass distribution of the nominal selection (black), control selection without correction (red), and control selection with correction (blue) for data (solid histograms) and a simulation of a signal from a resonance with a mass of 400 GeV (dashed histograms). The correction, applied as a function of the product of the two largest jet transverse momenta in the event, is obtained as the ratio of the numbers of events passing the signal selection to those passing the control selection. For ease of readability, the dijet mass distributions of the signal have been scaled by an arbitrary factor. The bottom plot shows the relative difference between the dijet mass distributions of the data from the control and nominal selections. The yield of the uncorrected control selection for data is 95.7% of the nominal selection. The overlap between the two data selections is about 35% of the nominal selection. The yield of the uncorrected control selection for signal simulation of a 400-GeV resonance is about 50% of the nominal selection.

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Version 2
Search for dark photons in decays of Higgs bosons produced in association with Z bosons in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1748735 DOI 10.17182/hepdata.89702

A search is presented for a Higgs boson that is produced in association with a Z boson and that decays to an undetected particle together with an isolated photon. The search is performed by the CMS Collaboration at the Large Hadron Collider using a data set corresponding to an integrated luminosity of 137 fb$^{-1}$ recorded at a center-of-mass energy of 13 TeV. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for associated Higgs and Z boson production and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a mass of 125 GeV, assuming the standard model production cross section, this corresponds to an observed (expected) upper limit on this branching fraction of 4.6 (3.6)% at 95% confidence level. These are the first limits on Higgs boson decays to final states that include an undetected massless dark photon.

12 data tables

Observed yields, background estimates after the fit to data, and signal predictions after the event selection in the signal region. The signal size corresponds to $0.1 \sigma_{\mathrm{\mathrm{ZH}}}$ for all three $m_{\mathrm{\mathrm{H}}}$ values shown. The combined statistical and systematic uncertainties are reported.

Covariance matrix for all bins used in the analysis. There are 45 bins in total, 15 for every data-taking year. For every year, the first bin corresponds to events in the $\mathrm{e}\mu$ control region, the following five bins correspond to events with $|\eta^\gamma|< 1$ in the signal region, the next five bins correspond to events with $|\eta^\gamma|> 1$ in the signal region, the next two bins correspond to events in the WZ control region, and finally the last two bins correspond to events in the ZZ control region.

Electron reconstruction, identification, and isolation efficiency as a function of $|\eta|$ and $\mathrm{p_\mathrm{T}}$.

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Search for heavy Higgs bosons decaying to a top quark pair in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1747886 DOI 10.17182/hepdata.89937

A search is presented for additional scalar (H) or pseudoscalar (A) Higgs bosons decaying to a top quark pair in proton-proton collisions at a center-of-mass energy of 13 TeV. The data set analyzed corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected by the CMS experiment at the LHC. Final states with one or two charged leptons are considered. The invariant mass of the reconstructed top quark pair system and variables that are sensitive to the spin of the particles decaying into the top quark pair are used to search for signatures of the H or A bosons. The interference with the standard model top quark pair background is taken into account. A moderate signal-like deviation compatible with an A boson with a mass of 400 GeV is observed with a global significance of 1.9 standard deviations. New stringent constraints are reported on the strength of the coupling of the hypothetical bosons to the top quark, with the mass of the bosons ranging from 400 to 750 GeV and their total relative width from 0.5 to 25%. The results of the search are also interpreted in a minimal supersymmetric standard model scenario. Values of $m_\mathrm{A}$ from 400 to 700 GeV are probed, and a region with values of $\tan\beta$ below 1.0 to 1.5, depending on $m_\mathrm{A}$, is excluded at 95% confidence level.

13 data tables

Exclusion in the (mA, tan beta) plane of the hMSSM. Both H and A boson signals are included with masses and widths that correspond to a given point in the plane.

Model-independent constraints on the coupling strength modifier as a function of the heavy scalar boson mass, for a relative width of 0.5%.

Model-independent constraints on the coupling strength modifier as a function of the heavy scalar boson mass, for a relative width of 1.0%.

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Search for anomalous triple gauge couplings in WW and WZ production in lepton + jet events in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1744608 DOI 10.17182/hepdata.91970

A search is presented for three additional operators that would lead to anomalousWW$\gamma$ or WWZ couplings with respect to those in the standard model. They are constrained by studying events with two vector bosons; a W boson decaying to e$\nu$ or $\mu\nu$, and a W or Z boson decaying hadronically, reconstructed as a single, massive, large-radius jet. The search uses a data set of proton-proton collisions at a centre-of-mass energy of 13 TeV, recorded by the CMS experiment at the CERN LHC in 2016, and corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Using the reconstructed diboson invariant mass, 95% confidence intervals are obtained for the anomalous coupling parameters of $-$1.58 $< c_\mathrm{WWW}/\Lambda^2 <$ 1.59 TeV$^{-2}$, $-$2.00 $< c_\mathrm{W}/\Lambda^2 <$ 2.65 TeV$^{-2}$, and $-$8.78$ < c_\mathrm{B}/\Lambda^2 <$ 8.54 TeV$^{-2}$, in agreement with standard model expectations of zero for each parameter. These are the strictest bounds on these parameters to date.

8 data tables

aTGC limits on EFT parameters in lepton + jet events in WW and WZ production

2-dimensional aTGC limits in lepton + jet events in WW and WZ production

aTGC limits in LEP parametrization in lepton + jet events in WW and WZ production

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Search for light pseudoscalar boson pairs produced from decays of the 125 GeV Higgs boson in final states with two muons and two nearby tracks in pp collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1744267 DOI 10.17182/hepdata.90694

A search is presented for pairs of light pseudoscalar bosons, in the mass range from 4 to 15 GeV, produced from decays of the 125 GeV Higgs boson. The decay modes considered are final states that arise when one of the pseudoscalars decays to a pair of tau leptons, and the other one either into a pair of tau leptons or muons. The search is based on proton-proton collisions collected by the CMS experiment in 2016 at a center-of-mass energy of 13 TeV that correspond to an integrated luminosity of 35.9 fb${-1}$. The 2$\mu$2$\tau$ and 4$\tau$ channels are used in combination to constrain the product of the Higgs boson production cross section and the branching fraction into 4$\tau$ final state, $\sigma\mathcal{B}$, exploiting the linear dependence of the fermionic coupling strength of pseudoscalar bosons on the fermion mass. No significant excess is observed beyond the expectation from the standard model. The observed and expected upper limits at 95% confidence level on $\sigma\mathcal{B}$, relative to the standard model Higgs boson production cross section, are set respectively between 0.022 and 0.23 and between 0.027 and 0.19 in the mass range probed by the analysis.

1 data table

Expected and observed 95% CL upper limits on (sigma(pp->h)/sigma(pp->hSM)) * B(h -> aa -> tautautautau) as a function of m(a) obtained from the 13 TeV data, where h(SM) is the Higgs boson of the standard model, h is the observed particle with mass of 125 GeV, and (a) denotes a light Higgs-like state.


Measurement of the top quark polarization and $\mathrm{t\bar{t}}$ spin correlations using dilepton final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1742786 DOI 10.17182/hepdata.90640

Measurements of the top quark polarization and top quark pair ($\mathrm{t\bar{t}}$) spin correlations are presented using events containing two oppositely charged leptons (e$^+$e$^-$, e$^\pm\mu^\mp$, or $\mu^+\mu^-$) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb$^{-1}$. A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the $\mathrm{t\bar{t}}$ production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to -0.24 $<C_\text{tG}/\Lambda^{2} < $ 0.07 TeV$^{-2}$ and -0.33 $< C^{I}_\text{tG}/\Lambda^{2} < $ 0.20 TeV$^{-2}$, respectively, at 95% confidence level.

29 data tables

Figure 5, normalized differential cross section for $\cos\theta_{1}^{k*}$

Figure 4, normalized differential cross section for $\cos\theta_{1}^{k}$

Figure 6, normalized differential cross section for $\cos\theta_{1}^{k}\cos\theta_{2}^{k}$

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Search for MSSM Higgs bosons decaying to $\mu^+\mu^-$ in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1742776 DOI 10.17182/hepdata.90684

A search is performed for neutral non-standard-model Higgs bosons decaying to two muons in the context of the minimal supersymmetric standard model (MSSM). Proton-proton collision data recorded by the CMS experiment at the CERN Large Hadron Collider at a center-of-mass energy of 13 TeV were used, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The search is sensitive to neutral Higgs bosons produced via the gluon fusion process or in association with a $\mathrm{b\overline{b}}$ quark pair. No significant deviations from the standard model expectation are observed. Upper limits at 95% confidence level are set in the context of the $m_\mathrm{h}^{\text{mod+}}$ and phenomenological MSSM scenarios on the parameter $\tan\beta$ as a function of the mass of the pseudoscalar A boson, in the range from 130 to 600 GeV. The results are also used to set a model-independent limit on the product of the branching fraction for the decay into a muon pair and the cross section for the production of a scalar neutral boson, either via gluon fusion, or in association with b quarks, in the mass range from 130 to 1000 GeV.

6 data tables

The 95% CL upper limits on tanb as a function of mA for the mhmod plus MSSM scenario

The 95% CL upper limits on tanb as a function of mA for the hMSSM scenario

The 95% CL upper limits on the production cross section times the branching fraction as a function of mA in the case of a b-associated production

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Version 2
Search for long-lived particles using nonprompt jets and missing transverse momentum with proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett. B797 (2019) 134876, 2019.
Inspire Record 1740108 DOI 10.17182/hepdata.90583

A search for long-lived particles decaying to displaced, nonprompt jets and missing transverse momentum is presented. The data sample corresponds to an integrated luminosity of 137 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC in 2016-2018. Candidate signal events containing nonprompt jets are identified using the timing capabilities of the CMS electromagnetic calorimeter. The results of the search are consistent with the background prediction and are interpreted using a gauge-mediated supersymmetry breaking reference model with a gluino next-to-lightest supersymmetric particle. In this model, gluino masses up to 2100, 2500, and 1900 GeV are excluded at 95% confidence level for proper decay lengths of 0.3, 1, and 100 m, respectively. These are the best limits to date for such massive gluinos with proper decay lengths greater than $\sim$0.5 m.

28 data tables

The distribution (normalized to unity) of number of ECAL cells hit in the jet for jets in a background enriched data sample (satisfying $|\eta| < 1.48$, $PV_{\rm track}^{\rm fraction} > 1/12$, $\mathrm{HEF} > 0.2$, $t_{\mathrm{jet}} < -3\,\mathrm{ns}$ and $E^{\mathrm{CSC}}_\mathrm{ECAL}/E_{\mathrm{ECAL}} < 0.8$) and for signal jets satisfying signal region requirements (except those on $E_{\mathrm{ECAL}}$ and $N^{\mathrm{cell}}_{\mathrm{ECAL}}$).

Selection efficiencies for the GMSB model with $m_{\tilde{g}}=1000$ and various proper decay lengths

Summary of the estimated number of background events.

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