Heavy Resonances Research Articles

Search for heavy resonances in final states with four leptons and missing transverse momentum or jets in pp collisions at s\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\sqrt{s} $$\\end{document} = 13 TeV with the ATLAS detector

A search for a new heavy boson produced via gluon-fusion in the four-lepton channel with missing transverse momentum or jets is performed. The search uses proton-proton collision data equivalent to an integrated luminosity of 139 fb−1 at a centre-of-mass energy of 13 TeV collected by the ATLAS detector between 2015 and 2018 at the Large Hadron Collider. This study explores the decays of heavy bosons: R → SH and A → ZH, where R is a CP-even boson, A is a CP-odd boson, H is a CP-even boson, and S is considered to decay into invisible particles that are candidates for dark matter. In these processes, S → invisible and H → ZZ. The Z boson associated with the heavy scalar boson H decays into all decay channels of the Z boson. The mass range under consideration is 390–1300 (320–1300) GeV for the R (A) boson and 220–1000 GeV for the H boson. No significant deviation from the Standard Model backgrounds is observed. The results are interpreted as upper limits at a 95% confidence level on the cross-section times the branching ratio of the heavy resonances.

Heavy four-quark mesons [formula omitted]: Scalar particle

Parameters of the heavy four-quark scalar meson Tbcb‾c‾ with content bcb‾c‾ are calculated by means of the sum rule method. This structure is considered as a diquark-antidiquark state built of scalar diquark and antidiquark components. The mass and current coupling of Tbcb‾c‾ are evaluated in the context of the two-point sum rule approach. The full width of this tetraquark is estimated by taking into account two types of its possible strong decay channels. First class includes dissociation of Tbcb‾c‾ to mesons ηcηb, Bc+Bc−, Bc⁎+Bc⁎− and Bc+(13P0)Bc⁎−. Another type of processes are generated by annihilations b‾b→q‾q of constituent b-quarks which produces the final-state charmed meson pairs D+D−, D0D‾0, D⁎+D⁎−, and D⁎0D‾⁎0. Partial width all of these decays are found using the three-point sum rule method which is required to calculate strong couplings at corresponding meson-meson-tetraquark vertices. Predictions obtained for the mass m=(12697±90)MeV and width Γ[Tbcb‾c‾]=(142.4±16.9)MeV of this state are compared with alternative results, and are useful for further experimental investigations of fully heavy resonances.

Scalar exotic mesons bbc¯c¯

Properties of doubly charged scalar tetraquarks bbc¯c¯ are investigated in the framework of the Quantum Chromodynamic (QCD) sum rule method. We model them as diquark–antidiquark states X 1 and X 2 built of axial-vector and pseudoscalar diquarks, respectively. The masses and current couplings of these particles are computed using the QCD two-point sum rule method. Results m 1 = (12715 ± 80) MeV and m 2 = (13370 ± 95) MeV obtained for the masses of these particles are used to determine their kinematically allowed decay modes. The full width Γ1 of the state X 1 is evaluated by taking into account its strong decays to mesons 2Bc− , and 2Bc*− . The processes X2→2Bc− , 2Bc*− and Bc−Bc−(2S) are employed to estimate Γ2. Predictions obtained for the full widths Γ1 = (63 ± 12) MeV and Γ2 = (79 ± 14) MeV of these structures and their masses may be utilized in experimental studies of fully heavy resonances.

Search for pair production of boosted Higgs bosons via vector-boson fusion in the [formula omitted] final state using pp collisions at [formula omitted] with the ATLAS detector

A search for Higgs boson pair production via vector-boson fusion is performed in the Lorentz-boosted regime, where a Higgs boson candidate is reconstructed as a single large-radius jet, using 140 fb−1 of proton–proton collision data at s=13 TeV recorded by the ATLAS detector at the Large Hadron Collider. Only Higgs boson decays into bottom quark pairs are considered. The search is particularly sensitive to the quartic coupling between two vector bosons and two Higgs bosons relative to its Standard Model prediction, κ2V. This study constrains κ2V to 0.55<κ2V<1.49 at the 95% confidence level. The value κ2V=0 is excluded with a significance of 3.8 standard deviations with other Higgs boson couplings fixed to their Standard Model values. A search for new heavy spin-0 resonances that would mediate Higgs boson pair production via vector-boson fusion is carried out in the mass range of 1–5 TeV for the first time under several model and decay-width assumptions. No significant deviation from the Standard Model hypothesis is observed and exclusion limits at the 95% confidence level are derived.

Searches for New High-Mass Resonances Decaying to Fermions at the LHC

Accelerator searches for new resonances have a long-standing history of discoveries that have driven advances in our understanding of nature. Since 2010, the Large Hadron Collider (LHC) has probed previously inaccessible energy scales, enabling searches for new heavy resonances predicted by a wide range of theories beyond the Standard Model (BSM). In particular, resonance decays into fermionic final states are often seen as golden channels since they provide a clear signal—typically a peak in the invariant mass of the decay products over a smoothly falling background distribution. This review summarizes the key concepts of the experimental searches for new resonances decaying to fermions, in the context of the BSM theories that motivate them, and presents the latest results of the ATLAS and CMS experiments, focusing on the complete LHC Run 2 dataset. Future prospects at the High-Luminosity LHC and potential future colliders are also surveyed.

Finetuning foundation models for joint analysis optimization in High Energy Physics

In this work we demonstrate that significant gains in performance and data efficiency can be achieved in High Energy Physics (HEP) by moving beyond the standard paradigm of sequential optimization or reconstruction and analysis components. We conceptually connect HEP reconstruction and analysis to modern machine learning workflows such as pretraining, finetuning, domain adaptation and high-dimensional embedding spaces and quantify the gains in the example usecase of searches of heavy resonances decaying via an intermediate di-Higgs system to four b-jets. To our knowledge this is the first example of a low-level feature extraction network finetuned for a downstream HEP analysis objective.

The effect of cutoff dependence on heavy quark spin symmetry partners

Hadron spectroscopy is revealed by observing heavy resonances. Among various explanations of the internal structure of these hadronic states, hadronic molecules play a unique role. For hadronic molecules, which are associated with meson–meson or meson–baryon interactions, the [Formula: see text] cutoff is a significant factor in determining the composite states’ binding energies and overall properties. The cutoff becomes important when it comes to the location of hadronic molecules’ masses because it influences the predictions. From this perspective, in the light of cutoff dependency, heavy quark spin partners of near-threshold the [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] resonances, which are considered as hadronic molecules, are examined.

Combination of searches for heavy spin-1 resonances using 139 fb−1 of proton-proton collision data at s\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\sqrt{s} $$\\end{document} = 13 TeV with the ATLAS detector

A combination of searches for new heavy spin-1 resonances decaying into different pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fb−1 of proton-proton collisions at s\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\sqrt{s} $$\\end{document} = 13 TeV collected during 2015–2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb, tt¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ t\\overline{t} $$\\end{document}, and tb) or third-generation leptons (τν and ττ) are included in this kind of combination for the first time. A simplified model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confidence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion.

Heavy axial-vector structures [formula omitted

The fully heavy axial-vector diquark-antidiquark structures bbc‾c‾ are explored by means of the QCD sum rule method. They are modeled as four-quark mesons T1 and T2 composed of bTCσμνγ5b, c‾γνCc‾T and bTCγμγ5b, c‾Cc‾T diquarks, respectively. The spectroscopic parameters of the tetraquarks T1 and T2 are determined in the context of the QCD two-point sum rule method. Results obtained for masses of these states m1=(12715±86)MeV and m2=(13383±92)MeV are used to fix their strong decay channels. The full width Γ(T1) of the diquark-antidiquark state T1 is estimated by considering the processes T1→Bc−Bc⁎− and T1→Bc⁎−Bc⁎−. The decays to mesons Bc−Bc⁎−, Bc−(2S)Bc⁎− and Bc⁎−Bc⁎− are employed to evaluate Γ(T2). Results obtained for the widths Γ(T1)=(44.3±8.8)MeV and Γ(T2)=(82.5±13.7)MeV of these tetraquarks in conjunction with their masses are useful for future experimental studies of fully heavy resonances.

Search for top-philic heavy resonances in pp collisions at s=13\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sqrt{s}=13$$\\end{document} TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document} with the ATLAS detector

A search for the associated production of a heavy resonance with a top-quark or a top-antitop-quark pair, and decaying into a tt¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$t{\\bar{t}}$$\\end{document} pair is presented. The search uses the data recorded by the ATLAS detector in pp collisions at s=13\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sqrt{s}= 13$$\\end{document} TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document} at the Large Hadron Collider during the years 2015–2018, corresponding to an integrated luminosity of 139 fb-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {fb}^{-1}$$\\end{document}. Events containing exactly one electron or muon are selected. The two hadronically decaying top quarks from the resonance decay are reconstructed using jets clustered with a large radius parameter of R=1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$R=1$$\\end{document}. The invariant mass spectrum of the two top quark candidates is used to search for a resonance signal in the range of 1.0 TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document} to 3.2 TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document}. The presence of a signal is examined using an approach with minimal model dependence followed by a model-dependent interpretation. No significant excess is observed over the background expectation. Upper limits on the production cross section times branching ratio at 95% confidence level are provided for a heavy Z′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Z^\\prime $$\\end{document} boson based on a simplified model, for Z′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Z^\\prime $$\\end{document} mass between 1.0 TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document} and 3.0 TeV\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext {TeV}$$\\end{document}. The observed (expected) limits range from 21 (14) fb to 119 (86) fb depending on the choice of model parameters.

Di-Higgs signatures in neutral naturalness

The Higgs boson was the last fundamental piece of the Standard Model to be experimentally confirmed. LHC is embarked in a quest to probe the possibility that this particle provides a portal to new physics. One front of this quest consists in measuring the interactions of the Higgs with itself and with other SM particles to a high precision. In a more exotic front, the LHC is searching for the possibility that a pair of Higgses (HH) is the evidence of a new resonance. Such resonances are predicted in models with extended Higgs sectors, extra dimensions, and in models with exotic bound states. In this paper we show how scalar quirks in Folded Supersymmetry can give rise to HH resonances. We point out a viable sector of the parameter space in which HH is the dominant decay channel for these squirkonium bound states. We found that future runs of the LHC could discover HH resonances in the range of 0.5–1.6 TeV under reasonable assumptions. Furthermore, for a given mass and width of the HH signal, the model predicts the branching ratio of the subsequent decay modes of the heavy resonance. Finding the extra decay modes in the predicted pattern can serve as a smoking gun to confirm the model.

Testing complex singlet scalar cosmology at the Large Hadron Collider

The Standard Model extended with a complex singlet scalar (cxSM) can admit a strong first order electroweak phase transition (SFOEWPT) as needed for electroweak baryogenesis and provide a dark matter (DM) candidate. The presence of both a DM candidate and a singlet-like scalar that mixes with the Standard Model Higgs boson leads to the possibility of a bb¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ b\\overline{b} $$\\end{document} + MET final state in pp collisions. Focusing on this channel, we analyze the prospective reach at the Large Hadron Collider (LHC) for a heavy singlet-like scalar in regions of cxSM parameter space compatible with a SFOEWPT and DM phenomenology. We identify this parameter space while implementing current constraints from electroweak precision observable and Higgs boson property measurements as well as those implied by LHC heavy resonance searches. Implementing a proposed search strategy, we find that the heavy scalar and DM candidate can be probed up to 1 TeV and 450 GeV at 2σ level respectively.

Higgs Physics Research: Yesterday, Today, and Tomorrow

This article reviews the discovery of the Higgs boson, discusses the studies of its properties, and introduces the physical prospects of the future Higgs factories.&lt;br&gt;The greatest goal of particle physics is to understand the fundamental particles of the universe and how they interact (or more generally, how the universe works). In the Standard Model of particle phyiscs, the Higgs mechanism generates elementary particle masses and predicts the existence of the Higgs boson. Higgs physics is one of the most important research areas in particle physics.&lt;br&gt;The Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) accelerates beams of protons to collide them at a center-of-mass energy of 13 TeV, defining the world’s energy frontier. The ATLAS and CMS detectors are two general-purpose detectors at the LHC, studying the debris from the collisions.&lt;br&gt;The Higgs boson was discovered by the ATLAS and CMS experiments in 2012. This discovery completed the fundamental particle spectrum of the Standard Model and was a major milestone for particle physics. Since then, many studies of the Higgs boson properties (including spin, mass and couplings) have been performed to refine our understanding of the Higgs mechanism. In particular, the Higgs boson’s couplings to fermions and to itself are new kinds of fundamental interactions with paramount significance, and have not been fully established. Additionally, the Higgs boson has become an important tool to search for Dark Matter, heavy resonance, and other new physics phenomena. So far, there has been no deviation from the the Standard Model predictions.&lt;br&gt;Looking towards the future, electron-positron colliders have been proposed to study the Higgs boson more deeply. Physics studies have shown that these Higgs factories can largely improve precision on many properties of the Higgs boson (including width and couplings) and provide great physics prospects.

Heavy resonances and the oblique parameters S and T

It has been confirmed experimentally the existence of a mass gap between Standard Model (SM) and eventual Beyond Standard Model (BSM) fields. Therefore, the use of effective approaches to search for fingerprints of New Physics is very appealing. A non-linear realizations of the Electroweak Symmetry Breaking is considered here, where the Higgs is a singlet with free couplings and the SM fields are also coupled to bosonic heavy resonances. A one-loop-level calculation of the oblique S and T parameters is presented here. This analysis allows us to constrain resonance masses to be above the TeV scale, ▪TeV, in good agreement with our previous determinations, where these observables were computed with a more simplified Lagrangian.

GAN-AE: an anomaly detection algorithm for New Physics search in LHC data

In recent years, interest has grown in alternative strategies for the search for New Physics beyond the Standard Model. One envisaged solution lies in the development of anomaly detection algorithms based on unsupervised machine learning techniques. In this paper, we propose a new Generative Adversarial Network-based auto-encoder model that allows both anomaly detection and model-independent background modeling. This algorithm can be integrated with other model-independent tools in a complete heavy resonance search strategy. The proposed strategy has been tested on the LHC Olympics 2020 dataset with promising results.

Impact of multi-characteristics on heavy metals sensor-based surface plasmonic resonance

Impact of multi-characteristics on heavy metals sensor-based surface plasmonic resonance

A guide to diagnosing colored resonances at hadron colliders

We present a comprehensive study on how to distinguish the properties of heavy dijet resonances at hadron colliders. A variety of spins, chiral couplings, charges, and QCD color representations are considered. Distinguishing the different color representations is particularly difficult at hadron colliders. To determine the QCD color structure, we consider a third jet radiated in a resonant dijet event. We show that the relative rates of three-jet versus two-jet processes are sensitive to the color representation of the resonance. We also show analytically that the antennae radiation pattern of soft radiation depends on the color structure of dijet events and develops an observable that is sensitive to the antennae patterns. Finally, we exploit a Convolutional Neural Network with Machine Learning techniques to differentiate the radiation patterns from different colored resonances and find encouraging results to discriminate them. We demonstrate our results numerically at a 14 TeV LHC, and the methodology presented here should be applicable to other future hadron colliders.

Search for single production of vector-like T quarks decaying into Ht or Zt in pp collisions at sqrt{s} = 13 TeV with the ATLAS detector

This paper describes a search for the single production of an up-type vector-like quark (T) decaying as T → Ht or T → Zt. The search utilises a dataset of pp collisions at sqrt{s} = 13 TeV collected with the ATLAS detector during the 2015–2018 data-taking period of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb−1. Data are analysed in final states containing a single lepton with multiple jets and b-jets. The presence of boosted heavy resonances in the event is exploited to discriminate the signal from the Standard Model background. No significant excess above the Standard Model expectation is observed, and 95% CL upper limits are set on the production cross section of T quarks in different decay channels. The results are interpreted in several benchmark scenarios to set limits on the mass and universal coupling strength (κ) of the vector-like quark. For singlet T quarks, κ values above 0.53 are excluded for all masses below 2.3 TeV. At a mass of 1.6 TeV, κ values as low as 0.35 are excluded. For T quarks in the doublet scenario, where the production cross section is much lower, κ values above 0.72 are excluded for all masses below 1.7 TeV, and this exclusion is extended to κ above 0.55 for low masses around 1.0 TeV.

Search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state in proton-proton collisions at [formula omitted

A search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state is presented. The analysis is based on proton-proton collision data recorded by the CMS detector in 2016–2018 at a centre-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 138fb−1. The search is sensitive to resonances with masses between 1.3 and 6TeV, decaying to bosons that are highly Lorentz-boosted such that each of the bosons forms a single large-radius jet. Machine learning techniques are employed to identify such jets. No significant excess over the estimated standard model background is observed. A maximum local significance of 3.6 standard deviations, corresponding to a global significance of 2.3 standard deviations, is observed at masses of 2.1 and 2.9 TeV. In a heavy vector triplet model, spin-1 Z′ and W′ resonances with masses below 4.8TeV are excluded at the 95% confidence level (CL). These limits are the most stringent to date. In a bulk graviton model, spin-2 gravitons and spin-0 radions with masses below 1.4 and 2.7TeV, respectively, are excluded at 95% CL. Production of heavy resonances through vector boson fusion is constrained with upper cross section limits at 95% CL as low as 0.1fb.

Search for the production of dark matter candidates in association with heavy dimuon resonance using the CMS open data for proton–proton collisions at sqrt{s} = 8 TeV

In this work, we present a search for the possible production of Dark Matter particles at the Large Hadron Collider alongside a new hypothetical neutral gauge boson denoted by {Z}^{prime }. The topology of the studied events is dimuons plus large missing transverse momentum. The study is performed using the CMS open data samples collected by the CMS experiment in the LHC proton–proton collisions at center-of-mass energy of 8 TeV in 2012, which corresponds to an integrated luminosity of 11.6 hbox {fb}^{-1}, and the corresponding CMS open Monte Carlo samples. Two benchmark scenarios were used for interpreting the data, the Dark Higgs scenario and the effective field theory formalism. No evidence for the existence of dark matter candidates was found. 95% confidence level limits are set on the masses of the {Z}^{prime } and the cutoff scale of the effective field theory.