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1. Search for supersymmetry in final states with a single electron or muon using angular correlations and heavy-object identification in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV

   https://doi.org/10.1007/JHEP09(2023)149  

   Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Damanakis, K.; Dragicevic, M.; Escalante Del Valle, A.; Hussain, P. S.; Jeitler, M.; et al (September 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> A search for supersymmetry is presented in events with a single charged lepton, electron or muon, and multiple hadronic jets. The data correspond to an integrated luminosity of 138 fb⁻¹of proton-proton collisions at a center-of-mass energy of 13 TeV, recorded by the CMS experiment at the CERN LHC. The search targets gluino pair production, where the gluinos decay into final states with the lightest supersymmetric particle (LSP) and either a top quark-antiquark ($$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$) pair, or a light-flavor quark-antiquark ($$ \textrm{q}\overline{\textrm{q}} $$ $q\overline{q}$) pair and a virtual or on-shell W boson. The main backgrounds,$$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$pair and W+jets production, are suppressed by requirements on the azimuthal angle between the momenta of the lepton and of its reconstructed parent W boson candidate, and by top quark and W boson identification based on a machine-learning technique. The number of observed events is consistent with the expectations from standard model processes. Limits are evaluated on supersymmetric particle masses in the context of two simplified models of gluino pair production. Exclusions for gluino masses reach up to 2120 (2050) GeV at 95% confidence level for a model with gluino decay to a$$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$pair (a$$ \textrm{q}\overline{\textrm{q}} $$ $q\overline{q}$pair and a W boson) and the LSP. For the same models, limits on the mass of the LSP reach up to 1250 (1070) GeV. 

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2. Measurement of the top quark pole mass using $$ \textrm{t}\overline{\textrm{t}} $$+jet events in the dilepton final state in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV

   https://doi.org/10.1007/JHEP07(2023)077  

   Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Damanakis, K.; Dragicevic, M.; Escalante Del Valle, A.; Hussain, P. S.; Jeitler, M.; et al (July 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> A measurement of the top quark pole mass$$ {m}_{\textrm{t}}^{\textrm{pole}} $$ $m_t^{\text{pole}}$in events where a top quark-antiquark pair ($$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$) is produced in association with at least one additional jet ($$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$+jet) is presented. This analysis is performed using proton-proton collision data at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV collected by the CMS experiment at the CERN LHC, corresponding to a total integrated luminosity of 36.3 fb⁻¹. Events with two opposite-sign leptons in the final state (e⁺e⁻,μ⁺μ⁻, e^±μ^∓) are analyzed. The reconstruction of the main observable and the event classification are optimized using multivariate analysis techniques based on machine learning. The production cross section is measured as a function of the inverse of the invariant mass of the$$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$+jet system at the parton level using a maximum likelihood unfolding. Given a reference parton distribution function (PDF), the top quark pole mass is extracted using the theoretical predictions at next-to-leading order. For the ABMP16NLO PDF, this results in$$ {m}_{\textrm{t}}^{\textrm{pole}} $$ $m_t^{\text{pole}}$= 172.93±1.36 GeV. 

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3. Measurement of the $$ \textrm{t}\overline{\textrm{t}}\textrm{H} $$ and tH production rates in the H → $$ \textrm{b}\overline{\textrm{b}} $$ decay channel using proton-proton collision data at $$ \sqrt{s} $$ = 13 TeV

   https://doi.org/10.1007/JHEP02(2025)097  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (February 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> An analysis of the production of a Higgs boson (H) in association with a top quark-antiquark pair ($$ \textrm{t}\overline{\textrm{t}}\textrm{H} $$ $t\overline{t}H$) or a single top quark (tH) is presented. The Higgs boson decay into a bottom quark-antiquark pair (H →$$ \textrm{b}\overline{\textrm{b}} $$ $b\overline{b}$) is targeted, and three different final states of the top quark decays are considered, defined by the number of leptons (electrons or muons) in the event. The analysis utilises proton-proton collision data collected at the CERN LHC with the CMS experiment at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV in 2016–2018, which correspond to an integrated luminosity of 138 fb⁻¹. The observed$$ \textrm{t}\overline{\textrm{t}}\textrm{H} $$ $t\overline{t}H$production rate relative to the standard model expectation is 0.33 ± 0.26 = 0.33 ± 0.17(stat) ± 0.21(syst). Additionally, the$$ \textrm{t}\overline{\textrm{t}}\textrm{H} $$ $t\overline{t}H$production rate is determined in intervals of Higgs boson transverse momentum. An upper limit at 95% confidence level is set on the tH production rate of 14.6 times the standard model prediction, with an expectation of$$ {19.3}_{-6.0}^{+9.2} $$ ${19.3}_{-6.0}^{+9.2}$. Finally, constraints are derived on the strength and structure of the coupling between the Higgs boson and the top quark from simultaneous extraction of the$$ \textrm{t}\overline{\textrm{t}}\textrm{H} $$ $t\overline{t}H$and tH production rates, and the results are combined with those obtained in other Higgs boson decay channels. 

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4. Measurements of inclusive and differential cross sections for top quark production in association with a Z boson in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV

   https://doi.org/10.1007/JHEP02(2025)177  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (February 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> Measurements are presented of inclusive and differential cross sections for Z boson associated production of top quark pairs ($$ \textrm{t}\overline{\textrm{t}}\textrm{Z} $$ $t\overline{t}Z$) and single top quarks (tZq or tWZ). The data were recorded in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb⁻¹. Events with three or more leptons, electrons or muons, are selected and a multiclass deep neural network is used to separate three event categories, the$$ \textrm{t}\overline{\textrm{t}}\textrm{Z} $$ $t\overline{t}Z$and tWZ processes, the tZq process, and the backgrounds. A profile likelihood approach is used to unfold the differential cross sections, to account for systematic uncertainties, and to determine the correlations between the two signal categories in one global fit. The inclusive cross sections for a dilepton invariant mass between 70 and 110 GeV are measured to be 1.14 ± 0.07 pb for the sum of$$ \textrm{t}\overline{\textrm{t}}\textrm{Z} $$ $t\overline{t}Z$and tWZ, and 0.81 ± 0.10 pb for tZq, in good agreement with theoretical predictions. 

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5. Differential cross section measurements for the production of top quark pairs and of additional jets using dilepton events from pp collisions at $$ \sqrt{s} $$ = 13 TeV

   https://doi.org/10.1007/JHEP02(2025)064  

   Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Escalante_Del_Valle, A; Hussain, P S; Jeitler, M; et al (February 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> Differential cross sections for top quark pair ($$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$) production are measured in proton-proton collisions at a center-of-mass energy of 13 TeV using a sample of events containing two oppositely charged leptons. The data were recorded with the CMS detector at the CERN Large Hadron Collider and correspond to an integrated luminosity of 138 fb⁻¹. The differential cross sections are measured as functions of kinematic observables of the$$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$system, the top quark and antiquark and their decay products, as well as of the number of additional jets in the event. The results are presented as functions of up to three variables and are corrected to the parton and particle levels. When compared to standard model predictions based on quantum chromodynamics at different levels of accuracy, it is found that the calculations do not always describe the observed data. The deviations are found to be largest for the multi-differential cross sections. 

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