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A search for the pair production of heavy spin- $1/2$ or spin- $3/2$ resonances ( $t^{*}$ ) in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ is presented. Data collected with the CMS detector at the CERN LHC from 2016 to 2018 corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$ are used. The analysis targets benchmark signal scenarios where one $t^{*}$ decays into a top quark ( $t$ ) and a photon ( $\gamma$ ), and the other into a $t$ quark and a gluon ( $g$ ), i.e., $pp\to t^{*}\overline{t^{*}}\to tt\gamma g$ . All-hadronic final states from the $t$ pair decay chain are selected using jet substructure techniques. The signal is probed as a function of the $t^{*}$ candidate mass, which is reconstructed using the photon and a top quark candidate jet. No significant deviation from the background-only hypothesis is found. Observed (expected) upper limits on the signal cross section at 95% confidence level are set, excluding masses of spin- $1/2$ $t^{*}$ particles below 930 (930) GeV and spin- $3/2$ $t^{*}$ particles below 1330 (1390) GeV. This analysis marks the first search for heavy resonances in the $t\overline{t}\gamma g$ channel. Exploiting the high-energy photon to reduce the backgrounds, this search achieves sensitivity competitive with $pp\to t^{*}\overline{t^{*}}\to t\overline{t}gg$ searches for spin- $1/2$ $t^{*}$ despite the small expected $t^{*}\to t\gamma$ branching fraction. 

A<sc>bstract</sc> A measurement of the angular structure of inclusive jets and those containing a prompt D⁰meson in proton-proton collisions at the LHC at a center-of-mass energy of 5.02 TeV is presented. The data corresponding to an integrated luminosity of 301 pb⁻¹were collected by the CMS experiment in 2017. Two jet grooming algorithms, late-k_Tand soft drop, are used to study the intrajet radiation pattern using iterative Cambridge-Aachen declustering. The splitting-angle distributions of jets with transverse momentum (p_T) of around 100 GeV, obtained with these two algorithms, show that there is a shift of the distribution for jets containing a prompt D⁰meson with respect to inclusive jets. The suppression of emissions at small angles observed in the late-k_Tgrooming approach is consistent with the dead-cone effect, whereas the similar suppression for splittings selected with the soft-drop algorithm appears to be induced by gluon splitting to charm quark-antiquark pairs at large angles. The measured distributions are corrected to the particle level and can be used to constrain model predictions for the substructure of high-p_Tcharm quark jets. 

A<sc>bstract</sc> A search for nonresonant new physics phenomena in high-mass dilepton events produced in association with b-tagged jets is performed using proton-proton collision data collected in 2016–2018 by the CMS experiment at the CERN LHC, at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb⁻¹. The analysis considers two effective field theory models with dimension-six operators; involving four-fermion contact interactions between two leptons (ℓℓ, electrons or muons) and b or s quarks (bbℓℓand bsℓℓ). Two lepton flavor combinations (ee andμμ) are required and events are classified as having 0, 1, or ≥2 b-tagged jets in the final state. No significant excess is observed over the standard model backgrounds. Upper limits are set on the production cross section of the new physics signals. These translate into lower limits on the energy scale Λ of 6.9 to 9.0 TeV in the bbℓℓmodel, depending on model parameters, and on the ratio of energy scale and effective coupling, Λ/g_*, of 2.0 to 2.6 TeV in the bsℓℓmodel. Lepton flavor universality is also tested by comparing the dielectron (ee) and dimuon (μμ) mass spectra for different b-tagged jet multiplicities. No significant deviation from the standard model expectation of unity is observed. 

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, $H\to c\overline{c}$ , produced in association with a top quark-antiquark pair ( $t\overline{t}H$ ) is presented. The search is performed with data from proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ , corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$ . Advanced machine learning techniques are employed for jet flavor identification and event classification. The Higgs boson decay to a bottom quark-antiquark pair is measured simultaneously and the observed $t\overline{t}H\left(H\to b\overline{b}\right)$ event rate relative to the standard model expectation is ${0.91}_{-0.22}^{+0.26}$ . The observed (expected) upper limit on the product of production cross section and branching fraction $\sigma \left(t\overline{t}H\right)\mathcal{B}(H\to c\overline{c})$ is 0.11 (0.13) pb at 95% confidence level, corresponding to 7.8 (8.7) times the standard model prediction. When combined with the previous search for $H\to c\overline{c}$ via associated production with a $W$ or $Z$ boson, the observed (expected) 95% confidence interval on the Higgs-charm Yukawa coupling modifier, ${\kappa }_c$ , is $\left|{\kappa }_c\right|<3.5$ (2.7), the most stringent constraint to date. 

A<sc>bstract</sc> Measurements are presented of the W and Z boson production cross sections in proton-proton collisions at a center-of-mass energy of 13.6 TeV. Data collected in 2022 and corresponding to an integrated luminosity of 5.01 fb⁻¹with one or two identified muons in the final state are analyzed. The results for the products of total inclusive cross sections and branching fractions for muonic decays of W and Z bosons are$${11}.{93}\pm 0.0{8}\left({\text{syst}}\right)\pm 0.{17}{\left({\text{lumi}}\right)}_{-0.07}^{+0.07}$$(acceptance) nb for W⁺boson production,$$8.86\pm 0.06\left({\text{syst}}\right)\pm 0.12{\left({\text{lu}}{\text{mi}}\right)}_{-0.06}^{+0.05}$$(acceptance) nb for W⁻boson production, and$$2.021\pm 0.009\left({\text{syst}}\right)\pm 0.028{\left({\text{lumi}}\right)}_{-0.013}^{+0.011}$$(acceptance) nb for the Z boson production in the dimuon mass range of 60–120 GeV, all with negligible statistical uncertainties. Furthermore, the corresponding fiducial cross sections, as well as cross section ratios for both fiducial and total phase space, are provided. The ratios include charge-separated results for W boson production (W⁺and W⁻) and the sum of the two contributions (W^±), each relative to the measured Z boson production cross section. Additionally, the ratio of the measured cross sections for W⁺and W⁻boson production is reported. All measurements are in agreement with theoretical predictions, calculated at next-to-next-to-leading order accuracy in quantum chromodynamics. 

Using proton-proton collision data collected by the CMS experiment at $\sqrt{s}=13\mathrm{TeV}$ in 2016–2018, corresponding to an integrated luminosity of $140{\mathrm{fb}}^{-1}$ , the first full reconstruction of the three vector $B$ meson states, $B^{*+}$ , $B^{*0}$ , and $B_s^{*0}$ , is performed. The mass differences between the excited mesons and their corresponding ground states are measured to be $m\left(B^{*+}\right)-m\left(B^{+}\right)=45.277\pm 0.039\pm 0.027\mathrm{MeV}$ , $m\left(B^{*0}\right)-m\left(B^0\right)=45.471\pm 0.056\pm 0.028\mathrm{MeV}$ , and $m\left(B_s^{*0}\right)-m\left(B_s^0\right)=49.407\pm 0.132\pm 0.041\mathrm{MeV}$ , where the first uncertainties are statistical and the second are systematic. These results improve on the precision of previous measurements by an order of magnitude. 

Abstract The traditional quark model^1,2accounts for the existence of baryons, such as protons and neutrons, which consist of three quarks, as well as mesons, composed of a quark–antiquark pair. Only recently has substantial evidence started to accumulate for exotic states composed of four or five quarks and antiquarks³. The exact nature of their internal structure remains uncertain^4–29. Here we report the first measurement of quantum numbers of the recently discovered family of three all-charm tetraquarks^30–32, using data collected by the CMS experiment at the Large Hadron Collider from 2016 to 2018 (refs. ^33,34). The angular analysis techniques developed for the discovery and characterization of the Higgs boson^35–37have been applied to the new exotic states. Here we show that the quantum numbers for parityPand charge conjugationCsymmetries are found to be +1. The spinJof these exotic states is determined to be consistent with 2ħ, while 0ħand 1ħare excluded at 95% and 99% confidence levels, respectively. TheJ^PC = 2⁺⁺assignment implies particular configurations of constituent spins and orbital angular momenta, which constrain the possible internal structure of these tetraquarks. 

A search for $\gamma H$ production is performed with data from the CMS experiment at the LHC corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$ at a proton-proton center-of-mass collision energy of $13\mathrm{TeV}$ . The analysis focuses on the topology of a boosted Higgs boson recoiling against a high-energy photon. The final states of $H\to b\overline{b}$ and $H\to 4\ell$ are analyzed. This study examines effective $HZ\gamma$ and $H\gamma \gamma$ anomalous couplings within the context of an effective field theory. In this approach, the production cross section is constrained to be ${\sigma }_{\gamma H}<16.4\mathrm{fb}$ at 95% confidence level (CL). Simultaneous constraints on four anomalous couplings involving $HZ\gamma$ and $H\gamma \gamma$ are provided. Additionally, the production rate for $H\to 4\ell$ is examined to assess potential enhancements in the Yukawa couplings between light quarks and the Higgs boson. Assuming the standard model values for the Yukawa couplings of the bottom and top quarks, the following simultaneous constraints are obtained: ${\kappa }_u=(0.0\pm 1.5)\times {10}^3$ , ${\kappa }_d=\left({0.0}_{-6.8}^{+6.7}\right)\times {10}^2$ , ${\kappa }_s=0_{-32}^{+30}$ , and ${\kappa }_c={0.0}_{-2.8}^{+2.3}$ . This rules out the hypothesis that up- or down-type quarks in the first or second generation have the same Yukawa couplings as those in the third generation, with a CL greater than 95%. 

A measurement of event-shape variables is presented, using a data sample produced in a special run with approximately one inelastic proton-proton collision per bunch crossing. The data were collected with the CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of $64\mathrm{\mu }{\mathrm{b}}^{-1}$ . A number of observables related to the overall distribution of charged particles in the collisions are corrected for detector effects and compared with simulations. Inclusive event-shape distributions, as well as differential distributions of event shapes as functions of charged-particle multiplicity, are studied. None of the models investigated are able to satisfactorily describe the data. Moreover, there are significant features common amongst all generator setups studied, particularly showing data being more isotropic than any of the simulations. Multidimensional unfolded distributions are provided, along with their correlations.