Searches for physics beyond the standard model with the $M_\mathrm{T2}$ variable in hadronic final states with and without disappearing tracks in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 80 (2020) 3, 2020.
Inspire Record 1753215 DOI 10.17182/hepdata.90834

Two related searches for phenomena beyond the standard model (BSM) are performed using events with hadronic jets and significant transverse momentum imbalance. The results are based on a sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 137 fb$^{-1}$. The first search is inclusive, based on signal regions defined by the hadronic energy in the event, the jet multiplicity, the number of jets identified as originating from bottom quarks, and the value of the kinematic variable $M_\mathrm{T2}$ for events with at least two jets. For events with exactly one jet, the transverse momentum of the jet is used instead. The second search looks in addition for disappearing tracks produced by BSM long-lived charged particles that decay within the volume of the tracking detector. No excess event yield is observed above the predicted standard model background. This is used to constrain a range of BSM models that predict the following: the pair production of gluinos and squarks in the context of supersymmetry models conserving $R$-parity, with or without intermediate long-lived charginos produced in the decay chain; the resonant production of a colored scalar state decaying to a massive Dirac fermion and a quark; or the pair production of scalar and vector leptoquarks each decaying to a neutrino and a top, bottom, or light-flavor quark. In most of the cases, the results obtained are the most stringent constraints to date.

52 data tables

Definitions of super signal regions, along with predictions, observed data, and the observed 95% CL upper limits on the number of signal events contributing to each region ($N_{95}^\mathrm{max}$). The limits are given under assumptions of 0% and 15% for the uncertainty on the signal acceptance. All selection criteria as in the full analysis are applied. For regions with $N_\mathrm{j}=1$, $H_\mathrm{T}\equiv p_\mathrm{T}^\mathrm{jet}$.

Exclusion limits at 95% CL for direct gluino pair production, where the gluinos decay to light-flavor quarks ($\tilde{g}\to q\bar{q}\tilde{\chi}_1^0$). Signal cross sections are calculated at approximately NNLO+NNLL order in $\alpha_S$, assuming unity branching fraction to $q\bar{q}\tilde{\chi}_1^0$.

Exclusion limits at 95% CL for direct gluino pair production, where the gluinos decay to light-flavor quarks and either a $\tilde{\chi}_2^0$ that decays to $Z\tilde{\chi}_1^0$ (1/3 of the time), or a $\tilde{\chi}_1^\pm$ that decays to $W^\pm\tilde{\chi}_1^0$ (2/3 of the time). Signal cross sections are calculated at approximately NNLO+NNLL order in $\alpha_S$, assuming unity branching fraction to $q_i\bar{q}_j V\tilde{\chi}_1^0$.

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A search for new physics in central exclusive production using the missing mass technique with the CMS detector and the CMS-TOTEM precision proton spectrometer

The CMS & TOTEM collaborations Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Eur.Phys.J.C 83 (2023) 827, 2023.
Inspire Record 2639338 DOI 10.17182/hepdata.135797

A generic search is presented for the associated production of a Z boson or a photon with an additional unspecified massive particle X, pp $\to$ pp + Z/$\gamma$ + X, in proton-tagged events from proton-proton collisions at $\sqrt{s}$ = 13 TeV, recorded in 2017 with the CMS detector and the CMS-TOTEM precision proton spectrometer. The missing mass spectrum is analysed in the 600-1600 GeV range and a fit is performed to search for possible deviations from the background expectation. No significant excess in data with respect to the background predictions has been observed. Model-independent upper limits on the visible production cross section of pp $\to$ pp + Z/$\gamma$ + X are set.

35 data tables

Comparison of the $m_{miss}$ shapes for the simulated signal events within the fiducial region and those outside it, after including the effect of PU protons as describe in the text, for a generated $m_{X}$ mass of 1000 GeV. The distributions are shown for multi(+z)-multi(−z) proton reconstruction categories.

Comparison of the $m_{miss}$ shapes for the simulated signal events within the fiducial region and those outside it, after including the effect of PU protons as describe in the text, for a generated $m_{X}$ mass of 1000 GeV. The distributions are shown for multi(+z)-single(−z) proton reconstruction categories.

Comparison of the $m_{miss}$ shapes for the simulated signal events within the fiducial region and those outside it, after including the effect of PU protons as describe in the text, for a generated $m_{X}$ mass of 1000 GeV. The distributions are shown for single(+z)-multi(−z) proton reconstruction categories.

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Version 4
Measurements of differential Z boson production cross sections in proton-proton collisions at $ \sqrt{s} $ = 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 12 (2019) 061, 2019.
Inspire Record 1753680 DOI 10.17182/hepdata.91215

Measurements are presented of the differential cross sections for Z bosons produced in proton-proton collisions at $\sqrt{s} =$ 13 TeV and decaying to muons and electrons. The data analyzed were collected in 2016 with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The measured fiducial inclusive product of cross section and branching fraction agrees with next-to-next-to-leading order quantum chromodynamics calculations. Differential cross sections of the transverse momentum $p_\mathrm{T}$, the optimized angular variable $\phi^*_\eta$, and the rapidity of lepton pairs are measured. The data are corrected for detector effects and compared to theoretical predictions using fixed order, resummed, and parton shower calculations. The uncertainties of the measured normalized cross sections are smaller than 0.5% for $\phi^*_\eta <$ 0.5 and for $p_\mathrm{T}^\mathrm{Z} <$ 50 GeV.

137 data tables

Summary of data, expected signal, and background yields after the full selection. The predicted signal yields are quoted using aMC@NLO simulation. The statistical uncertainties in the simulated samples are below 0.1%.

Summary of the systematic uncertainties for the inclusive fiducial cross section measurements.

The measured inclusive fiducial cross sections in the dimuon and dielectron final states. The combined measurement is also shown.

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Search for high-mass exclusive $\gamma\gamma\to WW$ and $\gamma\gamma\to ZZ$ production in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS & TOTEM collaborations Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 07 (2023) 229, 2023.
Inspire Record 2605178 DOI 10.17182/hepdata.135991

A search is performed for exclusive high-mass $\gamma\gamma$$\to$ WW and $\gamma\gamma$$\to$ ZZ production in proton-proton collisions using intact forward protons reconstructed in near-beam detectors, with both weak bosons decaying into boosted and merged jets. The analysis is based on a sample of proton-proton collisions collected by the CMS and TOTEM experiments at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 100 fb$^{-1}$. No excess above the standard model background prediction is observed, and upper limits are set on the pp $\to$ pWWp and pp $\to$ pZZp cross sections in a fiducial region defined by the diboson invariant mass $m$(VV) $\lt$ 1 TeV (with V = W, Z) and proton fractional momentum loss 0.04 $\lt$$\xi$$\lt$ 0.20. The results are interpreted as new limits on dimension-6 and dimension-8 anomalous quartic gauge couplings.

10 data tables

Expected and observed upper limits on the AQGC operators $a^W_0/\Lambda^2$, with no unitarization. The $y$ axis shows the limit on the ratio of the observed cross section to the cross section predicted for each anomalous coupling value ($\sigma_\mathrm{AQGC}$).

Expected and observed upper limits on the AQGC operators $a^W_C/\Lambda^2$, with no unitarization. The $y$ axis shows the limit on the ratio of the observed cross section to the cross section predicted for each anomalous coupling value ($\sigma_\mathrm{AQGC}$).

Expected and observed upper limits on the AQGC operators $a^Z_0/\Lambda^2$, with no unitarization. The $y$ axis shows the limit on the ratio of the observed cross section to the cross section predicted for each anomalous coupling value ($\sigma_\mathrm{AQGC}$).

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Version 2
Measurement of top quark pair production in association with a Z boson in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 03 (2020) 056, 2020.
Inspire Record 1746445 DOI 10.17182/hepdata.91636

A measurement of the inclusive cross section of top quark pair production in association with a Z boson using proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC is performed. The data sample corresponds to an integrated luminosity of 77.5 fb$^{-1}$, collected by the CMS experiment during 2016 and 2017. The measurement is performed using final states containing three or four charged leptons (electrons or muons), and the Z boson is detected through its decay to an oppositely charged lepton pair. The production cross section is measured to be $\sigma(\mathrm{t\bar{t}Z})$ $=$ 0.95 $\pm$ 0.05 (stat) $\pm$ 0.06 (syst) pb. For the first time, differential cross sections are measured as functions of the transverse momentum of the Z boson and the angular distribution of the negatively charged lepton from the Z boson decay. The most stringent direct limits to date on the anomalous couplings of the top quark to the Z boson are presented, including constraints on the Wilson coefficients in the framework of the standard model effective field theory.

24 data tables

Measured absolute differential tt̄Z production cross section in the full phase space as a function of the transverse momentum of the Z boson, compared to the predictions obtained with the MadGraph5_aMC@NLO MC simulation, and to the theory prediction at NLO+NNLL accuracy (1905.07815). The distribution $Δσ$ is integrated over the bin, and $\mathrm{d}σ/\mathrm{d}p_{\mathrm{T}}(\mathrm{Z})$ is additionally divided by the bin width. The last bin includes the overflow contribution, but a finite bin width is used for the normalization.

Measured absolute differential tt̄Z production cross section in the full phase space as a function of the transverse momentum of the Z boson, compared to the predictions obtained with the MadGraph5_aMC@NLO MC simulation, and to the theory prediction at NLO+NNLL accuracy (1905.07815). The distribution $Δσ$ is integrated over the bin, and $\mathrm{d}σ/\mathrm{d}p_{\mathrm{T}}(\mathrm{Z})$ is additionally divided by the bin width. The last bin includes the overflow contribution, but a finite bin width is used for the normalization.

Measured normalized differential tt̄Z production cross section in the full phase space as a function of the transverse momentum of the Z boson, compared to the predictions obtained with the MadGraph5_aMC@NLO MC simulation, and to the theory prediction at NLO+NNLL accuracy (1905.07815). The distribution $1/σ\,Δσ$ is integrated over the bin, and $1/σ\,\mathrm{d}σ/\mathrm{d}p_{\mathrm{T}}(\mathrm{Z})$ is additionally divided by the bin width. The last bin includes the overflow contribution, but a finite bin width is used for the normalization.

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Version 3
Measurements of production cross sections of WZ and same-sign WW boson pairs in association with two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 809 (2020) 135710, 2020.
Inspire Record 1794169 DOI 10.17182/hepdata.94181

Measurements of production cross sections of WZ and same-sign WW boson pairs in association with two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV at the LHC are reported. The data sample corresponds to an integrated luminosity of 137 fb$^{-1}$, collected with the CMS detector during 2016-2018. The measurements are performed in the leptonic decay modes W$^\pm$Z $\to$ $\ell^\pm\nu\ell'^\pm\ell'^\mp$ and WW $\to$ $\ell^\pm\nu\ell'^\pm\nu$, where $\ell, \ell' = $ e, $\mu$. Differential fiducial cross sections as functions of the invariant masses of the jet and charged lepton pairs, as well as of the leading-lepton transverse momentum, are measured for WW production and are consistent with the standard model predictions. The dependence of differential cross sections on the invariant mass of the jet pair is also measured for WZ production. An observation of electroweak production of WZ boson pairs is reported with an observed (expected) significance of 6.8 (5.3) standard deviations. Constraints are obtained on the structure of quartic vector boson interactions in the framework of effective field theory.

60 data tables

Relative systematic uncertainties in the EW $W^\pm W^\pm$ and WZ cross section measurements in units of percent.

Relative systematic uncertainties in the EW $W^\pm W^\pm$ and WZ cross section measurements in units of percent.

Relative systematic uncertainties in the EW $W^\pm W^\pm$ and WZ cross section measurements in units of percent.

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Measurements of the pp$\to$WZ inclusive and differential production cross section and constraints on charged anomalous triple gauge couplings at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 04 (2019) 122, 2019.
Inspire Record 1713417 DOI 10.17182/hepdata.89320

The WZ production cross section is measured in proton-proton collisions at a centre-of-mass energy $\sqrt{s} =$ 13 TeV using data collected with the CMS detector, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The inclusive cross section is measured to be $\sigma_{\text{tot}}$(pp $\to$ WZ$)$ = 48.09 $^{+1.00}_{-0.96}$ (stat) $^{+0.44}_{-0.37}$ (theo) $^{+2.39}_{-2.17}$ (syst) $\pm$ 1.39 (lumi) pb, resulting in a total uncertainty of $-$2.78/$+$2.98 pb. Fiducial cross section and ratios of charge-dependent cross section measurements are provided. Differential cross section measurements are also presented with respect to three variables: the Z boson transverse momentum $p_\mathrm{T}$, the leading jet $p_\mathrm{T}$, and the $m$(WZ) variable, defined as the invariant mass of the system composed of the three leptons and the missing transverse momentum. Differential measurements with respect to the W boson $p_\mathrm{T}$, separated by charge, are also shown. Results are consistent with standard model predictions, favouring next-to-next-to-leading-order predictions over those at next-to-leading order. Constraints on anomalous triple gauge couplings are derived via a binned maximum likelihood fit to the $m$(WZ) variable.

14 data tables

Differential cross section in bins of pT(Z). Values are expressed as a fraction of the total cross section. The eee and eem final states are shown.

Expected and observed one-dimensional confidence intervals (CI) at 95% confidence level for each of the considered EFT parameters, accounting only for the interference term between the SM amplitude and the BSM one. The one-dimensional intervals for each parameter are computed fixing the other two parameters to zero, the SM value.

Expected and observed one-dimensional confidence intervals (CI) at 95% confidence level for each of the considered EFT parameters. Both the square matrix of the dimension-6 contribution and the interference term between the SM amplitude and the BSM one are accounted for. The one-dimensional intervals for each parameter are computed fixing the other two parametes to zero, the SM value.

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Measurement of the average very forward energy as a function of the track multiplicity at central pseudorapidities in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 79 (2019) 893, 2019.
Inspire Record 1747892 DOI 10.17182/hepdata.91963

The average total energy as well as its hadronic and electromagnetic components are measured with the CMS detector at pseudorapidities $-$6.6 $<\eta<-$5.2 in proton-proton collisions at a centre-of-mass energy $\sqrt{s}=$ 13 TeV. The results are presented as a function of the charged particle multiplicity in the region $|\eta|< $2. This measurement is sensitive to correlations induced by the underlying event structure over a very wide pseudorapidity region. The predictions of Monte Carlo event generators commonly used in collider experiments and ultra-high energy cosmic ray physics are compared to the data.

5 data tables

Average total energy reconstructed in the region −6.6 < eta < −5.2 as a function of the number of reconstructed tracks for abs(eta)<2.

Average total energiy reconstructed in the region −6.6 < eta < −5.2 normalised to that in the first bin (Nch< 10) as a function of the number of reconstructed tracks for abs(eta)<2.

Average electromagnetic energy reconstructed in the region −6.6 < eta < −5.2 as a function of the number of reconstructed tracks for abs(eta)<2.

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Search for a heavy vector resonance decaying to a Z boson and a Higgs boson in proton-proton collisions at $\sqrt{s} = $ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 81 (2021) 688, 2021.
Inspire Record 1846987 DOI 10.17182/hepdata.101374

A search is presented for a heavy vector resonance decaying into a Z boson and the standard model Higgs boson, where the Z boson is identified through its leptonic decays to electrons, muons, or neutrinos, and the Higgs boson is identified through its hadronic decays. The search is performed in a Lorentz-boosted regime and is based on data collected from 2016 to 2018 at the CERN LHC, corresponding to an integrated luminosity of 137 fb$^{-1}$. Upper limits are derived on the production of a narrow heavy resonance Z', and a mass below 3.5 and 3.7 TeV is excluded at 95% confidence level in models where the heavy vector boson couples exclusively to fermions and to bosons, respectively. These are the most stringent limits placed on the Heavy Vector Triplet Z' model to date. If the heavy vector boson couples exclusively to standard model bosons, upper limits on the product of the cross section and branching fraction are set between 23 and 0.3 fb for a Z' mass between 0.8 and 4.6 TeV, respectively. This is the first limit set on a heavy vector boson coupling exclusively to standard model bosons in its production and decay.

21 data tables

The product of signal acceptance and efficiency in the 0l categories for the signal produced via qqbar annihilation.

The product of signal acceptance and efficiency in the 2l categories for the signal produced via qqbar annihilation.

The product of signal acceptance and efficiency in the 0l categories for the signal produced via vector boson fusion.

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Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 813 (2021) 136036, 2021.
Inspire Record 1817310 DOI 10.17182/hepdata.93883

Measurements of the second Fourier harmonic coefficient ($v_2$) of the azimuthal distributions of prompt and nonprompt D$^0$ mesons produced in pp and pPb collisions are presented. Nonprompt D$^0$ mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, $v_2$ signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum ($p_\mathrm{T}$) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D$^0$ meson $v_2$ values in pp and pPb collisions are similar in magnitude. The $v_2$ values for open beauty hadrons are extracted for the first time via nonprompt D$^0$ mesons in pPb collisions. For $p_\mathrm{T}$ in the range of 2-5 GeV, the results suggest that $v_2$ for nonprompt D$^0$ mesons are smaller than those for prompt D$^0$ mesons. These new measurements indicate a positive charm hadron $v_2$ in pp collisions and suggest a mass dependence in $v_2$ between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems.

8 data tables

Results of elliptic flow, corrected for short range correlations, for prompt neutral D mesons, as a function of transverse momenta for $|y_{lab}|< 1$, with $N^{offline}_{trk} \geq 100$ in pp collisions at 13 TeV.

Results of elliptic flow, corrected for short range correlations, for prompt neutral D mesons, as a function of multiplicity for $|y_{lab}|< 1$, with 2$ < p_{T} < $4 GeV in pp collisions at 13 TeV.

Results of elliptic flow, corrected for short range correlations, for prompt neutral D mesons, as a function of multiplicity for $|y_{lab}|< 1$, with 4$ < p_{T} < $6 GeV in pp collisions at 13 TeV.

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