Evidence for X(3872) in Pb-Pb Collisions and Studies of its Prompt Production at sqrt[s_{NN}]=5.02 TeV.

The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02  TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}.

Measurement of single-diffractive dijet production in proton-proton collisions at with the CMS and TOTEM experiments.

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss and the four-momentum transfer squared . Both processes and , i.e.

Studies of Charm Quark Diffusion inside Jets Using Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV.

The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC.

Search for physics beyond the standard model in events with jets and two same-sign or at least three charged leptons in proton-proton collisions at .

A data sample of events from proton-proton collisions with at least two jets, and two isolated same-sign or three or more charged leptons, is studied in a search for signatures of new physics phenomena. The data correspond to an integrated luminosity of at a center-of-mass energy of , collected in 2016-2018 by the CMS experiment at the LHC. The search is performed using a total of 168 signal regions defined using several kinematic variables.

Measurements of tt[over ¯]H Production and the CP Structure of the Yukawa Interaction between the Higgs Boson and Top Quark in the Diphoton Decay Channel.

The first observation of the tt[over ¯]H process in a single Higgs boson decay channel with the full reconstruction of the final state (H→γγ) is presented, with a significance of 6.6 standard deviations (σ). The CP structure of Higgs boson couplings to fermions is measured, resulting in an exclusion of the pure CP-odd structure of the top Yukawa coupling at 3.

Study of central exclusive production in proton-proton collisions at and 13TeV.

Central exclusive and semiexclusive production of pairs is measured with the CMS detector in proton-proton collisions at the LHC at center-of-mass energies of 5.02 and 13TeV. The theoretical description of these nonperturbative processes, which have not yet been measured in detail at the LHC, poses a significant challenge to models.

Measurement of differential cross sections and charge ratios for -channel single top quark production in proton-proton collisions at .

A measurement is presented of differential cross sections for -channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13 by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9 , events containing one muon or electron and two or three jets are analysed.

Mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles in collisions at and 5.02 .

Anisotropies in the initial energy density distribution of the quark-gluon plasma created in high energy heavy ion collisions lead to anisotropies in the azimuthal distributions of the final-state particles known as collective anisotropic flow. Fourier harmonic decomposition is used to quantify these anisotropies. The higher-order harmonics can be induced by the same order anisotropies (linear response) or by the combined influence of several lower order anisotropies (nonlinear response) in the initial state.

Measurement of the Jet Mass Distribution and Top Quark Mass in Hadronic Decays of Boosted Top Quarks in pp Collisions at sqrt[s]=13 TeV.

A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at sqrt[s]=13  TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9  fb^{-1}.

Constraints on the χ_{c1} versus χ_{c2} Polarizations in Proton-Proton Collisions at sqrt[s]=8 TeV.

The polarizations of promptly produced χ_{c1} and χ_{c2} mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at sqrt[s]=8  TeV. The χ_{c} states are reconstructed via their radiative decays χ_{c}→J/ψγ, with the photons being measured through conversions to e^{+}e^{-}, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_{c2} to χ_{c1} yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ→μ^{+}μ^{-} decay, in three bins of J/ψ transverse momentum.

Search for a Narrow Resonance Lighter than 200 GeV Decaying to a Pair of Muons in Proton-Proton Collisions at sqrt[s]=13 TeV.

A search is presented for a narrow resonance decaying to a pair of oppositely charged muons using sqrt[s]=13  TeV proton-proton collision data recorded at the LHC. In the 45-75 and 110-200 GeV resonance mass ranges, the search is based on conventional triggering and event reconstruction techniques. In the 11.

Search for direct pair production of supersymmetric partners to the lepton in proton-proton collisions at .

A search is presented for slepton pairs produced in proton-proton collisions at a center-of-mass energy of 13 . The search is carried out in events containing two leptons in the final state, on the assumption that each slepton decays primarily to a lepton and a neutralino. Events are considered in which each lepton decays to one or more hadrons and a neutrino, or in which one of the leptons decays instead to an electron or a muon and two neutrinos.

A multi-dimensional search for new heavy resonances decaying to boosted , , or boson pairs in the dijet final state at 13 .

A search in an all-jet final state for new massive resonances decaying to , , or boson pairs using a novel analysis method is presented. The analysis is performed on data corresponding to an integrated luminosity of 77.3 recorded with the CMS experiment at the LHC at a centre-of-mass energy of 13  .

Search for production of four top quarks in final states with same-sign or multiple leptons in proton-proton collisions at .

The standard model (SM) production of four top quarks ( ) in proton-proton collisions is studied by the CMS Collaboration. The data sample, collected during the 2016-2018 data taking of the LHC, corresponds to an integrated luminosity of 137 at a center-of-mass energy of 13 . The events are required to contain two same-sign charged leptons (electrons or muons) or at least three leptons, and jets.

Search for Supersymmetry with a Compressed Mass Spectrum in Events with a Soft τ Lepton, a Highly Energetic Jet, and Large Missing Transverse Momentum in Proton-Proton Collisions at sqrt[s]=13 TeV.

The first search for supersymmetry in events with an experimental signature of one soft, hadronically decaying τ lepton, one energetic jet from initial-state radiation, and large transverse momentum imbalance is presented. These event signatures are consistent with direct or indirect production of scalar τ leptons (τ[over ˜]) in supersymmetric models that exhibit coannihilation between the τ[over ˜] and the lightest neutralino (χ[over ˜]_{1}^{0}), and that could generate the observed relic density of dark matter. The data correspond to an integrated luminosity of 77.

Searches for physics beyond the standard model with the variable in hadronic final states with and without disappearing tracks in proton-proton collisions at .

Two related searches for phenomena beyond the standard model (BSM) are performed using events with hadronic jets and significant transverse momentum imbalance. The results are based on a sample of proton-proton collisions at a center-of-mass energy of , collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 137 . The first search is inclusive, based on signal regions defined by the hadronic energy in the event, the jet multiplicity, the number of jets identified as originating from bottom quarks, and the value of the kinematic variable for events with at least two jets.

Extraction and validation of a new set of CMS pythia8 tunes from underlying-event measurements.

New sets of CMS underlying-event parameters ("tunes") are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO.

Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets.

Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at sqrt[s]=13  TeV, and correspond to an integrated luminosity of 35.

Measurement of the average very forward energy as a function of the track multiplicity at central pseudorapidities in proton-proton collisions at .

The average total energy as well as its hadronic and electromagnetic components are measured with the CMS detector at pseudorapidities in proton-proton collisions at a centre-of-mass energy . The results are presented as a function of the charged particle multiplicity in the region . This measurement is sensitive to correlations induced by the underlying event structure over a very wide pseudorapidity region.

Measurements of triple-differential cross sections for inclusive isolated-photon+jet events in collisions at .

Measurements are presented of the triple-differential cross section for inclusive isolated-photon+jet events in collisions at TeV as a function of photon transverse momentum ( ), photon pseudorapidity ( ), and jet pseudorapidity ( ). The data correspond to an integrated luminosity of that probe a broad range of the available phase space, for and , , , and jet transverse momentum, , > 25 . The measurements are compared to next-to-leading order perturbative quantum chromodynamics calculations, which reproduce the data within uncertainties.

Search for Low-Mass Quark-Antiquark Resonances Produced in Association with a Photon at sqrt[s]=13 TeV.

A search for narrow low-mass resonances decaying to quark-antiquark pairs is presented. The search is based on proton-proton collision events collected at 13 TeV by the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 35.

Search for new physics in top quark production in dilepton final states in proton-proton collisions at .

A search for new physics in top quark production is performed in proton-proton collisions at . The data set corresponds to an integrated luminosity of collected in 2016 with the CMS detector. Events with two opposite-sign isolated leptons (electrons or muons), and quark jets in the final state are selected.

Azimuthal separation in nearly back-to-back jet topologies in inclusive 2- and 3-jet events in collisions at .

A measurement for inclusive 2- and 3-jet events of the azimuthal correlation between the two jets with the largest transverse momenta, , is presented. The measurement considers events where the two leading jets are nearly collinear ("back-to-back") in the transverse plane and is performed for several ranges of the leading jet transverse momentum. Proton-proton collision data collected with the CMS experiment at a center-of-mass energy of and corresponding to an integrated luminosity of are used.