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CMS-EXO-24-010 ; CERN-EP-2026-260
Search for nonresonant production of strongly coupled dark matter in proton-proton collisions at $ \sqrt{s}= $ 13 TeV
Submitted to the Journal of High Energy Physics
Abstract: A search is presented for semivisible jets produced in nonresonant processes, using proton-proton collision data at $ \sqrt{s}= $ 13 TeV, collected with the CMS detector at the CERN LHC and corresponding to an integrated luminosity of 138 fb$ ^{-1} $. These jets, containing both visible and invisible particles, would indicate the presence of dark matter arising from a strongly coupled hidden sector. The signal model includes a bifundamental scalar that couples simultaneously to standard model quarks and dark-sector quarks, the latter forming semivisible jets. The final state therefore includes missing transverse momentum aligned with a jet, rather than recoiling against standard model particles as typically required by conventional collider dark-matter searches. Two separate machine-learning strategies are employed to identify semivisible jets: a supervised graph neural network and an unsupervised autoencoder. No significant excess corresponding to dark-sector signal hypotheses is observed. Upper limits at 95% confidence level on the signal production cross section are determined for each strategy and interpreted as exclusions in the signal model parameter space. The supervised search excludes mediator masses between 0.5 and 2.4 TeV, depending on the other signal model parameters. For signal models with semivisible jets containing higher fractions of stable dark-matter particles, the unsupervised search demonstrates increased sensitivity with 5 (11)% higher expected (observed) mediator mass exclusions than the supervised search.
Figures & Tables Summary References CMS Publications
Figures

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Figure 1:
Representative Feynman diagrams of leading-order production of dark quarks $ \chi $ through a bifundamental mediator $ \Phi $. Left: $ t $-channel production of dark quarks. Middle: associated production of $ \Phi $ with a dark quark. Right: $ \Phi $ pair production.

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Figure 1-a:
Representative Feynman diagrams of leading-order production of dark quarks $ \chi $ through a bifundamental mediator $ \Phi $. Left: $ t $-channel production of dark quarks. Middle: associated production of $ \Phi $ with a dark quark. Right: $ \Phi $ pair production.

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Figure 1-b:
Representative Feynman diagrams of leading-order production of dark quarks $ \chi $ through a bifundamental mediator $ \Phi $. Left: $ t $-channel production of dark quarks. Middle: associated production of $ \Phi $ with a dark quark. Right: $ \Phi $ pair production.

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Figure 1-c:
Representative Feynman diagrams of leading-order production of dark quarks $ \chi $ through a bifundamental mediator $ \Phi $. Left: $ t $-channel production of dark quarks. Middle: associated production of $ \Phi $ with a dark quark. Right: $ \Phi $ pair production.

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Figure 2:
Unit-normalized distributions of the discriminating variables $ S_{\mathrm{T}} $, $ \Delta\phi_{\text{min}} $, and $ p_{\mathrm{T}}^\text{miss} $ for the simulated SM backgrounds and several signal models. For each variable, all preselection criteria are applied except the selection on that variable. The vertical black dotted line indicates the preselection requirement on the variable, with the arrow indicating the region of the distribution included in the analysis.

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Figure 2-a:
Unit-normalized distributions of the discriminating variables $ S_{\mathrm{T}} $, $ \Delta\phi_{\text{min}} $, and $ p_{\mathrm{T}}^\text{miss} $ for the simulated SM backgrounds and several signal models. For each variable, all preselection criteria are applied except the selection on that variable. The vertical black dotted line indicates the preselection requirement on the variable, with the arrow indicating the region of the distribution included in the analysis.

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Figure 2-b:
Unit-normalized distributions of the discriminating variables $ S_{\mathrm{T}} $, $ \Delta\phi_{\text{min}} $, and $ p_{\mathrm{T}}^\text{miss} $ for the simulated SM backgrounds and several signal models. For each variable, all preselection criteria are applied except the selection on that variable. The vertical black dotted line indicates the preselection requirement on the variable, with the arrow indicating the region of the distribution included in the analysis.

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Figure 2-c:
Unit-normalized distributions of the discriminating variables $ S_{\mathrm{T}} $, $ \Delta\phi_{\text{min}} $, and $ p_{\mathrm{T}}^\text{miss} $ for the simulated SM backgrounds and several signal models. For each variable, all preselection criteria are applied except the selection on that variable. The vertical black dotted line indicates the preselection requirement on the variable, with the arrow indicating the region of the distribution included in the analysis.

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Figure 3:
The PARTICLENET score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV and $ \lambda = $ 1 (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training PARTICLENET are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 3-a:
The PARTICLENET score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV and $ \lambda = $ 1 (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training PARTICLENET are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 3-b:
The PARTICLENET score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV and $ \lambda = $ 1 (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training PARTICLENET are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 4:
The WNAE score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV, $ \lambda = $ 1 (right), after applying the preselection criteria, for the model trained on jets with 200 $ < p_{\mathrm{T}} < $ 300 GeV. The lower panel shows the ratio between the data and the simulated background. The fluctuations of the WNAE AUC at low $ r_{\text{inv}} $ and $ m_{\Phi} $ arise from the limited number of events in this region. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 4-a:
The WNAE score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV, $ \lambda = $ 1 (right), after applying the preselection criteria, for the model trained on jets with 200 $ < p_{\mathrm{T}} < $ 300 GeV. The lower panel shows the ratio between the data and the simulated background. The fluctuations of the WNAE AUC at low $ r_{\text{inv}} $ and $ m_{\Phi} $ arise from the limited number of events in this region. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 4-b:
The WNAE score distribution for data, background simulation, and a selection of signal models scaled for visibility (left), and the performance discriminating between the simulated QCD background and signal models with varying $ m_{\Phi} $ and $ r_{\text{inv}} $ values with $ m_{\text{dark}} = $ 20 GeV, $ \lambda = $ 1 (right), after applying the preselection criteria, for the model trained on jets with 200 $ < p_{\mathrm{T}} < $ 300 GeV. The lower panel shows the ratio between the data and the simulated background. The fluctuations of the WNAE AUC at low $ r_{\text{inv}} $ and $ m_{\Phi} $ arise from the limited number of events in this region. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 5:
The event classifier output scores for data, background simulation, and a selection of signal models scaled for visibility (left) and the event classifier performance evaluated on a range of signal hypotheses with $ m_{\text{dark}}= $ 20 GeV, $ \lambda= $ 1, and varying $ r_{\text{inv}} $ and $ m_{\Phi} $, against the total background (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training the event classifier are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 5-a:
The event classifier output scores for data, background simulation, and a selection of signal models scaled for visibility (left) and the event classifier performance evaluated on a range of signal hypotheses with $ m_{\text{dark}}= $ 20 GeV, $ \lambda= $ 1, and varying $ r_{\text{inv}} $ and $ m_{\Phi} $, against the total background (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training the event classifier are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 5-b:
The event classifier output scores for data, background simulation, and a selection of signal models scaled for visibility (left) and the event classifier performance evaluated on a range of signal hypotheses with $ m_{\text{dark}}= $ 20 GeV, $ \lambda= $ 1, and varying $ r_{\text{inv}} $ and $ m_{\Phi} $, against the total background (right), after applying the preselection criteria. The lower panel shows the ratio between the data and the simulated background. The signal models used for training the event classifier are marked with a star. The simulated background score distributions are shown for illustration purposes only; they are not used to predict the SM background in the statistical interpretation. The signal jets are corrected for substructure-related mismodeling using their Lund jet plane density, as described in Section 4. The background simulation has no substructure correction applied. The statistical uncertainties in the data points are smaller than the marker size. The statistical uncertainty in the background simulation from the limited number of simulated events is shown, but is generally small.

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Figure 6:
The observed data, the postfit estimated background, and a representative signal model for the PARTICLENET supervised tagger strategy (upper) and for the WNAE unsupervised tagger strategy (lower). The background uncertainty includes both systematic and statistical components. The lower panels show the ratio of the observed data to the estimated background. The plots display all three years of data taking combined, while the actual fits consider each year independently.

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Figure 6-a:
The observed data, the postfit estimated background, and a representative signal model for the PARTICLENET supervised tagger strategy (upper) and for the WNAE unsupervised tagger strategy (lower). The background uncertainty includes both systematic and statistical components. The lower panels show the ratio of the observed data to the estimated background. The plots display all three years of data taking combined, while the actual fits consider each year independently.

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Figure 6-b:
The observed data, the postfit estimated background, and a representative signal model for the PARTICLENET supervised tagger strategy (upper) and for the WNAE unsupervised tagger strategy (lower). The background uncertainty includes both systematic and statistical components. The lower panels show the ratio of the observed data to the estimated background. The plots display all three years of data taking combined, while the actual fits consider each year independently.

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Figure 7:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{PN}} $ categories, for the PARTICLENET supervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 7-a:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{PN}} $ categories, for the PARTICLENET supervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 7-b:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{PN}} $ categories, for the PARTICLENET supervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 7-c:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{PN}} $ categories, for the PARTICLENET supervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 8:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{WNAE}} $ categories, for the WNAE unsupervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 8-a:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{WNAE}} $ categories, for the WNAE unsupervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 8-b:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{WNAE}} $ categories, for the WNAE unsupervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.

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Figure 8-c:
The exclusion limits as a function of $ m_{\Phi} $ and $ m_{\text{dark}} $ (upper left), $ m_{\Phi} $ and $ r_{\text{inv}} $ (upper right), and $ m_{\Phi} $ and $ \lambda $ (lower), combining all three data-taking years and all $ n_{\text{SVJ}}^{\text{WNAE}} $ categories, for the WNAE unsupervised tagger strategy. The dotted orange lines around the expected limit show the 68% CL interval. In the upper left plot, the $ m_{\text{dark}}^{\text{max}} $ value is obtained by combining Eqs. \eqrefeq:lambda_mass and \eqrefeq:shower_cond and rounding up to the nearest 10 GeV, with the minimum set to 20 GeV.
Tables

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Table 1:
The simulated background fractions [%] after applying the preselection criteria in the different $ n_{\text{SVJ}} $ categories for the PARTICLENET and WNAE SVJ taggers.

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Table 2:
The range of impacts in % on the signal yield at the preselection level or on the background yield in region A, for each corresponding systematic uncertainty. Values smaller than 0.01% are rounded to 0%. The second column shows the values for the baseline signal hypothesis with $ m_{\Phi} = $ 2 TeV, $ m_{\text{dark}} = $ 20 GeV, $ r_{\text{inv}} = $ 0.3, and $ \lambda = $ 1. The third column shows the 10--90% quantile range across all signal models.
Summary
The first CMS search for nonresonant production of strongly coupled dark matter has been presented. The search uses data from proton-proton collisions recorded with the CMS detector during the 2016--2018 data-taking period, corresponding to an integrated luminosity of 138 fb$ ^{-1} $ at a center-of-mass energy of 13 TeV. The signal model consists of a strongly coupled dark sector with several flavors of dark quarks that shower and hadronize to form stable and unstable bound states called dark hadrons. The stable dark hadrons are dark-matter candidates, while the unstable dark hadrons decay promptly to standard model (SM) quarks, showering and hadronizing in the visible sector to produce semivisible jets (SVJs) composed of both visible and invisible particles. This paper focuses on nonresonant production via a massive bifundamental scalar mediator $ \Phi $ with a Yukawa-like coupling between the dark and the SM sectors. The search probes variations of the mediator mass $ m_{\Phi} $, the dark-hadron mass $ m_{\text{dark}} $, the fraction of stable dark hadrons, and the bifundamental Yukawa coupling $ \lambda $. Two complementary strategies are employed to identify SVJs, yielding two sets of results. The first uses a supervised tagger, PARTICLENET, which is model-dependent and utilizes jet constituents to identify SVJs. The second uses an unsupervised tagger, the Wasserstein normalized autoencoder, to learn the substructure of SM jets in order to identify SVJs as anomalous jets. The response of these taggers is sensitive to potential mismodeling of the jet substructure in the signal simulation, which is corrected using a procedure designed for jets with high subjet multiplicity. This procedure compares the Lund jet plane of the signal subjets, each of which corresponds to one SM quark, to that of subjets from the hadronic decay of a W boson in observed data. For both the supervised and unsupervised tagger strategies, the SM background is estimated from data using an ``ABCD'' method in which a deep neural network discriminator is trained on event-level kinematic features to be decorrelated from the missing transverse momentum in order to partition events into four regions, separating signal from background. The unsupervised tagger strategy is particularly suited to searches for strongly coupled dark sectors, as many details of the signal model can subtly change the resulting jets and their substructure. Beyond the signal model parameters varied in this search, additional dark-sector parameters such as the number of dark-quark flavors and the number of dark colors, among others, may impact the visible behavior. The unsupervised tagger is trained independently from any signal model parameter choices and therefore has more consistent sensitivity in order to exclude a broader range of possible variations. The supervised tagger analysis places 95% confidence level exclusion limits on the production cross sections for different signal models, which can be interpreted to exclude ranges of signal model parameters. These exclusions include 0.5 $ < m_{\Phi} < $ 2.4 TeV, depending on the other signal model parameters. All considered values of $ m_{\text{dark}} $ are excluded for mediator masses below 1.7 TeV, depending on other signal parameters. For mediator masses less than 1.6 TeV, all considered variations of $ \lambda $ are excluded; for the full range of mediator masses considered, $ \lambda > $ 2 is excluded. Similarly, the unsupervised tagger analysis excludes 0.5 $ < m_{\Phi} < $ 2.1 TeV, depending on other signal model parameters. The unsupervised tagger analysis excludes all considered $ m_{\text{dark}} $ masses for mediator masses up to 1.6 TeV. For the full range of mediator masses considered, $ \lambda > $ 3 is excluded. These results complement existing searches for composite dark matter originating from strongly coupled dark sectors. A set of new signal hypotheses is excluded by placing limits on the inclusive production cross section for signal processes mediated by a massive bifundamental scalar $ \Phi $. The use of machine-learning techniques to exploit both jet- and event-level information increases the sensitivity of the search and enables the exclusion of a wide range of models in the targeted parameter space.
References
1 V. C. Rubin, N. Thonnard, and W. K. Ford, Jr. Rotational properties of 21 SC galaxies with a large range of luminosities and radii, from NGC 4605 (R = 4 kpc) to UGC 2885 (R = 122 kpc) Astrophys. J. 238 (1980) 471
2 M. Persic, P. Salucci, and F. Stel The universal rotation curve of spiral galaxies: I. The dark matter connection Mon. Not. Roy. Astron. Soc. 281 (1996) 27 astro-ph/9506004
3 D. Clowe et al. A direct empirical proof of the existence of dark matter Astrophys. J. 648 (2006) L109 astro-ph/0608407
4 DES Collaboration Dark Energy Survey year 1 results: curved-sky weak lensing mass map Mon. Not. Roy. Astron. Soc. 475 (2018) 3165 1708.01535
5 Planck Collaboration Planck 2018 results. VI. Cosmological parameters Astron. Astrophys. 641 (2020) A6 1807.06209
6 G. Jungman, M. Kamionkowski, and K. Griest Supersymmetric dark matter Phys. Rept. 267 (1996) 195 hep-ph/9506380
7 CMS Collaboration Search for new physics in final states with a single photon and missing transverse momentum in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JHEP 02 (2019) 074 CMS-EXO-16-053
1810.00196
8 CMS Collaboration Search for dark matter produced in association with a leptonically decaying Z boson in proton-proton collisions at $ \sqrt{s} = $ 13 TeV EPJC 81 (2021) 13 CMS-EXO-19-003
2008.04735
9 CMS Collaboration Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JHEP 11 (2021) 153 CMS-EXO-20-004
2107.13021
10 CMS Collaboration Search for invisible decays of a Higgs boson produced through vector boson fusion in proton-proton collisions at $ \sqrt{s} = $ 13 TeV PLB 793 (2019) 520 CMS-HIG-17-023
1809.05937
11 CMS Collaboration Search for dark matter particles in W$ ^{+} $W$ ^{-} $ events with transverse momentum imbalance in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JHEP 03 (2024) 134 CMS-EXO-21-012
2310.12229
12 ATLAS Collaboration Search for new particles in events with a hadronically decaying W or Z boson and large missing transverse momentum at $ \sqrt{s} = $ 13 TeV using the ATLAS detector JHEP 11 (2024) 126 2406.01272
13 ATLAS Collaboration Search for invisible Higgs boson decays in vector boson fusion at $ \sqrt{s} = $ 13 TeV with the ATLAS detector PLB 793 (2019) 499 1809.06682
14 ATLAS Collaboration Constraints on mediator-based dark matter and scalar dark energy models using $ \sqrt s = $ 13 TeV $ pp $ collision data collected by the ATLAS detector JHEP 05 (2019) 142 1903.01400
15 ATLAS Collaboration Search for new phenomena in events with two opposite-charge leptons, jets and missing transverse momentum in pp collisions at $ \sqrt{\mathrm{s}} = $ 13 TeV with the ATLAS detector JHEP 04 (2021) 165 2102.01444
16 ATLAS Collaboration Search for new phenomena with top quark pairs in final states with one lepton, jets, and missing transverse momentum in $ pp $ collisions at $ \sqrt{s} = $ 13 TeV with the ATLAS detector JHEP 04 (2021) 174 2012.03799
17 ATLAS Collaboration Search for new phenomena in events with an energetic jet and missing transverse momentum in $ pp $ collisions at $ \sqrt{s} = $ 13 TeV with the ATLAS detector PRD 103 (2021) 112006 2102.10874
18 ATLAS Collaboration Constraints on simplified dark matter models involving an $ s $-channel mediator with the ATLAS detector in pp collisions at $ \sqrt{s} = $ 13 TeV EPJC 84 (2024) 1102 2404.15930
19 CMS Collaboration Search for dark matter produced in association with a Higgs boson decaying to a pair of bottom quarks in proton--proton collisions at $ \sqrt{s}= $ 13 TeV EPJC 79 (2019) 280 CMS-EXO-16-050
1811.06562
20 CMS Collaboration Search for dark matter particles produced in association with a Higgs boson in proton-proton collisions at $ \sqrt{\text{s}} = $ 13 TeV JHEP 03 (2020) 025 CMS-EXO-18-011
1908.01713
21 CMS Collaboration Search for dark matter produced in association with a single top quark or a top quark pair in proton-proton collisions at $ \sqrt{s}= $ 13 TeV JHEP 03 (2019) 141 CMS-EXO-18-010
1901.01553
22 ATLAS Collaboration Search for dark matter produced in association with a single top quark and an energetic $ W $ boson in $ \sqrt{s}= $ 13 TeV $ pp $ collisions with the ATLAS detector EPJC 83 (2023) 603 2211.13138
23 CMS Collaboration Search for dark matter produced in association with one or two top quarks in proton-proton collisions at $ \sqrt{\text{s}} = $ 13 TeV JHEP 08 (2025) 085 CMS-EXO-22-014
2505.05300
24 CMS Collaboration Dark sector searches with the CMS experiment Phys. Rept. 1115 (2025) 448 CMS-EXO-23-005
2405.13778
25 ATLAS Collaboration Combination and summary of ATLAS dark matter searches interpreted in a 2HDM with a pseudo-scalar mediator using 139 $ \text{fb}^{-1} $ of $ \sqrt{s}= $ 13 TeV $ pp $ collision data Sci. Bull. 69 (2024) 3005 2306.00641
26 ATLAS Collaboration ATLAS Run 2 searches for electroweak production of supersymmetric particles interpreted within the pMSSM JHEP 05 (2024) 106 2402.01392
27 M. J. Strassler and K. M. Zurek Echoes of a hidden valley at hadron colliders PLB 651 (2007) 374 hep-ph/0604261
28 T. Cohen, M. Lisanti, H. K. Lou, and S. Mishra-Sharma LHC searches for dark sector showers JHEP 11 (2017) 196 1707.05326
29 P. Schwaller, D. Stolarski, and A. Weiler Emerging jets JHEP 05 (2015) 059 1502.05409
30 CMS Collaboration Search for new particles decaying to a jet and an emerging jet JHEP 02 (2019) 179 CMS-EXO-18-001
1810.10069
31 CMS Collaboration Search for dark QCD with emerging jets in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JHEP 07 (2024) 142 CMS-EXO-22-015
2403.01556
32 ATLAS Collaboration Search for emerging jets in $ pp $ collisions at $ \sqrt{s} = $ 13.6 TeV with the ATLAS experiment Rept. Prog. Phys. 88 (2025) 097801 2505.02429
33 ATLAS Collaboration Search for emerging jets in pp collisions at $ \sqrt{s} = $ 13 TeV with the ATLAS experiment EPJC 86 (2026) 808 2510.12347
34 M. J. Strassler Why unparticle models with mass gaps are examples of hidden valleys 0801.0629
35 S. Knapen, S. Pagan Griso, M. Papucci, and D. J. Robinson Triggering soft bombs at the LHC JHEP 08 (2017) 076 1612.00850
36 CMS Collaboration Search for soft unclustered energy patterns in proton-proton collisions at 13 TeV PRL 133 (2024) 191902 CMS-EXO-23-002
2403.05311
37 CMS Collaboration Search for soft unclustered energy patterns produced in association with a W or Z boson in proton-proton collisions at $ \sqrt{s}= $ 13 TeV PLB 879 (2026) 140671 CMS-EXO-25-007
2604.05996
38 ATLAS Collaboration Search for soft unclustered energy patterns containing muons in the final state in $ pp $ collisions at $ \sqrt{s} = $ 13 TeV with the ATLAS detector Submitted to \emphJHEP, 2026 2605.20015
39 CMS Collaboration Search for resonant production of strongly coupled dark matter in proton-proton collisions at 13 TeV JHEP 06 (2022) 156 CMS-EXO-19-020
2112.11125
40 ATLAS Collaboration Search for new physics in final states with semivisible jets or anomalous signatures using the ATLAS detector PRD 112 (2025) 012021 2505.01634
41 ATLAS Collaboration Search for non-resonant production of semi-visible jets using Run 2 data in ATLAS PLB 848 (2024) 138324 2305.18037
42 T. Cohen, M. Lisanti, and H. K. Lou Semi-visible jets: Dark matter undercover at the LHC PRL 115 (2015) 171804 1503.00009
43 CMS Collaboration Precision luminosity measurement in proton-proton collisions at $ \sqrt{s} = $ 13 TeV in 2015 and 2016 at CMS EPJC 81 (2021) 800 CMS-LUM-17-003
2104.01927
44 CMS Collaboration Precision luminosity measurement in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector at the Large Hadron Collider Submitted to Phys. Rev. X CMS-LUM-20-001
2606.26832
45 H. Qu and L. Gouskos ParticleNet: Jet tagging via particle clouds PRD 101 (2020) 056019 1902.08570
46 CMS Collaboration Wasserstein normalized autoencoder for anomaly detection Mach. Learn. Sci. Tech. 7 (2025) 035030 CMS-MLG-24-002
2510.02168
47 CMS Collaboration Machine learning method for enforcing variable independence in background estimation with LHC data: ABCDisCoTEC Mach. Learn. Sci. Tech. 7 (2026) 045071 CMS-MLG-23-003
2506.08826
48 CMS Collaboration HEPData record for this analysis link
49 CMS Collaboration The CMS experiment at the CERN LHC JINST 3 (2008) S08004
50 CMS Collaboration Development of the CMS detector for the CERN LHC Run 3 JINST 19 (2024) P05064 CMS-PRF-21-001
2309.05466
51 CMS Collaboration Performance of the CMS Level-1 trigger in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JINST 15 (2020) P10017 CMS-TRG-17-001
2006.10165
52 CMS Collaboration The CMS trigger system JINST 12 (2017) P01020 CMS-TRG-12-001
1609.02366
53 CMS Collaboration Performance of the CMS high-level trigger during LHC Run 2 JINST 19 (2024) P11021 CMS-TRG-19-001
2410.17038
54 CMS Collaboration Electron and photon reconstruction and identification with the CMS experiment at the CERN LHC JINST 16 (2021) P05014 CMS-EGM-17-001
2012.06888
55 CMS Collaboration Performance of the CMS muon detector and muon reconstruction with proton-proton collisions at $ \sqrt{s}= $ 13 TeV JINST 13 (2018) P06015 CMS-MUO-16-001
1804.04528
56 CMS Collaboration Description and performance of track and primary-vertex reconstruction with the CMS tracker JINST 9 (2014) P10009 CMS-TRK-11-001
1405.6569
57 J. Rosiek General mass insertion expansion in flavor physics in Proc. 5th Large Hadron Collider Physics Conf., 2017 1708.06818
58 A. Dedes et al. Mass insertions vs. mass eigenstates calculations in flavour physics JHEP 06 (2015) 151 1504.00960
59 X. Marcano and R. A. Morales Flavor techniques for LFV processes: Higgs decays in a general seesaw model Front. in Phys. 7 (2020) 228 1909.05888
60 R. Frederix et al. The automation of next-to-leading order electroweak calculations JHEP 07 (2018) 185 1804.10017
61 A. Alloul et al. FeynRules 2.0 - A complete toolbox for tree-level phenomenology Comput. Phys. Commun. 185 (2014) 2250 1310.1921
62 Y. Afik et al. DM+$ b\bar b $ simulations with DMSimp: an update in: Experimental and theoretical workshop, 2018
Proc. Dark Matter at the LHC 201 (2018) 8
1811.08002
63 T. Sjöstrand et al. An introduction to PYTHIA 8.2 Comput. Phys. Commun. 191 (2015) 159 1410.3012
64 G. Albouy et al. Theory, phenomenology, and experimental avenues for dark showers: a Snowmass 2021 report EPJC 82 (2022) 1132 2203.09503
65 J. Alwall et al. The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations JHEP 07 (2014) 079 1405.0301
66 J. Alwall et al. Comparative study of various algorithms for the merging of parton showers and matrix elements in hadronic collisions EPJC 53 (2008) 473 0706.2569
67 M. Beneke, P. Falgari, S. Klein, and C. Schwinn Hadronic top-quark pair production with NNLL threshold resummation NPB 855 (2012) 695 1109.1536
68 M. Cacciari et al. Top-pair production at hadron colliders with next-to-next-to-leading logarithmic soft-gluon resummation PLB 710 (2012) 612 1111.5869
69 P. B ä rnreuther, M. Czakon, and A. Mitov Percent level precision physics at the Tevatron: First genuine NNLO QCD corrections to $ \mathrm{q}\overline{\mathrm{q}}\to{\mathrm{t}\overline{\mathrm{t}}} +X $ PRL 109 (2012) 132001 1204.5201
70 M. Czakon and A. Mitov NNLO corrections to top-pair production at hadron colliders: the all-fermionic scattering channels JHEP 12 (2012) 054 1207.0236
71 M. Czakon and A. Mitov NNLO corrections to top pair production at hadron colliders: the quark-gluon reaction JHEP 01 (2013) 080 1210.6832
72 M. Czakon, P. Fiedler, and A. Mitov Total top-quark pair-production cross section at hadron colliders through $ O(\alpha_\mathrm{S}^4) $ PRL 110 (2013) 252004 1303.6254
73 Y. Li and F. Petriello Combining QCD and electroweak corrections to dilepton production in FEWZ PRD 86 (2012) 094034 1208.5967
74 NNPDF Collaboration Parton distributions from high-precision collider data EPJC 77 (2017) 663 1706.00428
75 CMS Collaboration Extraction and validation of a new set of CMS PYTHIA8 tunes from underlying-event measurements EPJC 80 (2020) 4 CMS-GEN-17-001
1903.12179
76 GEANT4 Collaboration GEANT 4---a simulation toolkit NIM A 506 (2003) 250
77 CMS Collaboration Particle-flow reconstruction and global event description with the CMS detector JINST 12 (2017) P10003 CMS-PRF-14-001
1706.04965
78 M. Cacciari, G. P. Salam, and G. Soyez The anti-$ k_{\mathrm{T}} $ jet clustering algorithm JHEP 04 (2008) 063 0802.1189
79 M. Cacciari, G. P. Salam, and G. Soyez FastJet user manual EPJC 72 (2012) 1896 1111.6097
80 CMS Collaboration Performance of missing transverse momentum reconstruction in proton-proton collisions at $ \sqrt{s} = $ 13 TeV using the CMS detector JINST 14 (2019) P07004 CMS-JME-17-001
1903.06078
81 CMS Collaboration Technical proposal for the Phase-II upgrade of the Compact Muon Solenoid CMS Technical Proposal CERN-LHCC-2015-010, CMS-TDR-15-02, 2015
CDS
82 CMS Collaboration Pileup mitigation at CMS in 13 TeV data JINST 15 (2020) P09018 CMS-JME-18-001
2003.00503
83 D. Bertolini, P. Harris, M. Low, and N. Tran Pileup per particle identification JHEP 10 (2014) 059 1407.6013
84 CMS Collaboration Jet energy scale and resolution in the CMS experiment in pp collisions at 8 TeV JINST 12 (2017) P02014 CMS-JME-13-004
1607.03663
85 E. Bols et al. Jet flavour classification using DeepJet JINST 15 (2020) P12012 2008.10519
86 CMS Collaboration Muon identification using multivariate techniques in the CMS experiment in proton-proton collisions at $ \sqrt{s}= $ 13 TeV JINST 19 (2024) P02031 CMS-MUO-22-001
2310.03844
87 K. Rehermann and B. Tweedie Efficient identification of boosted semileptonic top quarks at the LHC JHEP 03 (2011) 059 1007.2221
88 CMS Collaboration A method for correcting the substructure of multiprong jets using the Lund jet plane JHEP 11 (2025) 038 CMS-JME-23-001
2507.07775
89 F. A. Dreyer, G. P. Salam, and G. Soyez The Lund jet plane JHEP 12 (2018) 064 1807.04758
90 S. Yoon, Y.-K. Noh, and F. Park Autoencoding under normalization constraints in 38th Int. Conf. on Machine Learning, 2087
Proc. 3 (2087) 1
2105.05735
91 CMS Collaboration Performance of quark/gluon discrimination in 8 TeV pp data CMS-PAS-JME-13-002 CMS-PAS-JME-13-002
92 A. J. Larkoski, S. Marzani, G. Soyez, and J. Thaler Soft drop JHEP 05 (2014) 146 1402.2657
93 J. Thaler and K. Van Tilburg Identifying boosted objects with $ N $-subjettiness JHEP 03 (2011) 015 1011.2268
94 I. Moult, L. Necib, and J. Thaler New angles on energy correlation functions JHEP 12 (2016) 153 1609.07483
95 CDF Collaboration A measurement of $ \sigma B (W \to e \nu) $ and $ \sigma B (Z^0 \to e^+ e-) $ in $ \bar{p}p $ collisions at $ \sqrt{s} = $ 1800 GeV PRD 44 (1991) 29
96 G. Kasieczka, B. Nachman, M. D. Schwartz, and D. Shih Automating the ABCD method with machine learning PRD 103 (2021) 035021 2007.14400
97 W. Buttinger Background estimation with the ABCD method featuring the TRooFit toolkit
98 O. Behnke, K. Kröninger, G. Schott, and T. Schörner-Sadenius Data analysis in high energy physics: a practical guide to statistical methods eds., Wiley-VCH, Weinheim, Germany, 2013
link
99 A. Paszke et al. PyTorch: an imperative style, high-performance deep learning library in 33rd Int. Conf. on Neural Information, Curran Associates Inc, 2019
Proc. 3 (2019) 721
1912.01703
100 X. Glorot, A. Bordes, and Y. Bengio Deep sparse rectifier neural networks in 14th Int. Conf. on Artificial Intelligence and Statistics (AISTATS), G. Gordon, D. Dunson, and M. Dud\ík, eds., volume 15, 2011
Proc. 1 (2011) 315
101 G. J. Székely, M. L. Rizzo, and N. K. Bakirov Measuring and testing dependence by correlation of distances Ann. Stat. 35 (2007) 2769 0803.4101
102 J. Platt and A. Barr Constrained differential optimization in Proc. 1st Int. Conf. on Neural Information Processing Systems. MIT Press, Cambridge, MA, USA, 1987
link
103 CMS Collaboration Measurement of the inelastic proton-proton cross section at $ \sqrt{s}= $ 13 TeV JHEP 07 (2018) 161 CMS-FSQ-15-005
1802.02613
104 A. Kalogeropoulos and J. Alwall The SysCalc code: A tool to derive theoretical systematic uncertainties 1801.08401
105 S. Catani, D. de Florian, M. Grazzini, and P. Nason Soft gluon resummation for Higgs boson production at hadron colliders JHEP 07 (2003) 028 hep-ph/0306211
106 M. Cacciari et al. The $ \mathrm{t} \overline{\mathrm{t}} $ cross-section at 1.8 TeV and 1.96 TeV: a study of the systematics due to parton densities and scale dependence JHEP 04 (2004) 068 hep-ph/0303085
107 CMS Collaboration The CMS statistical analysis and combination tool: Combine Comput. Softw. Big Sci. 8 (2024) 19 CMS-CAT-23-001
2404.06614
108 T. Junk Confidence level computation for combining searches with small statistics NIM A 434 (1999) 435 hep-ex/9902006
109 A. L. Read Presentation of search results: the $ \text{CL}_\text{s} $ technique JPG 28 (2002) 2693
110 G. Cowan, K. Cranmer, E. Gross, and O. Vitells Asymptotic formulae for likelihood-based tests of new physics EPJC 71 (2011) 1554 1007.1727
Compact Muon Solenoid
LHC, CERN