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Abstract The performance is presented of the reconstruction and identification algorithms for electrons and photons with the CMS experiment at the LHC. The reported results are based on proton-proton collision data collected at a center-of-mass energy of 13 TeV and recorded in 2016–2018, corresponding to an integrated luminosity of 136 fb^-1. Results obtained from lead-lead collision data collected at √(s NN )=5.02 TeV are also presented. Innovative techniques are used to reconstruct the electro

A measurement of the top quark-antiquark pair production cross section tt in proton-proton collisions at a centre-of-mass energy of 13 TeV is presented. The data correspond to an integrated luminosity of 35.9 fb -1 , recorded by the CMS experiment at the CERN LHC in 2016. Dilepton events (e , + -, e + e -) are selected and the cross section is measured from a likelihood fit. For a top quark mass parameter in the simulation of m MC t = 172.5 GeV the fit yields a measured cross section tt = 803 2

An inclusive search for the standard model Higgs boson (H) produced with large transverse momentum (p_{T}) and decaying to a bottom quark-antiquark pair (bb[over ¯]) is performed using a data set of pp collisions at sqrt[s]=13 TeV collected with the CMS experiment at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb^{-1}. A highly Lorentz-boosted Higgs boson decaying to bb[over ¯] is reconstructed as a single, large radius jet, and it is identified using jet substructur

A bstract A search is performed for a heavy Majorana neutrino (N), produced in leptonic decay of a W boson propagator and decaying into a W boson and a lepton, with the CMS detector at the LHC. The signature used in this search consists of two same-sign leptons, in any flavor combination of electrons and muons, and at least one jet. The data were collected during 2016 in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb −1 . The r

A bstract Measurements are presented of the differential cross sections for Z bosons produced in proton-proton collisions at $$ \sqrt{s} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 13 TeV and decaying to muons and electrons. The data analyzed were collected in 2016 with the CMS detector at the LHC and correspond to an integrated luminosity of 35 . 9 fb − 1 . The measured fiducial inclusive product of cross section and bra

A measurement is presented of the effective leptonic weak mixing angle (sin 2 eff ) using the forwardbackward asymmetry of Drell-Yan lepton pairs ( and ee) produced in proton-proton collisions at s = 8 TeV at the CMS experiment of the LHC. The data correspond to integrated luminosities of 18.8 and 19.6 fb -1 in the dimuon and dielectron channels, respectively, containing 8.2 million dimuon and 4.9 million dielectron events. With more events and new analysis techniques, including constraints obta

Measurements of production cross sections of W Z and same-sign W W boson pairs in association with two jets in proton-proton collisions at s = 13 TeV at the LHC are reported. The data sample corresponds to an integrated luminosity of 137 fb − 1 , collected with the CMS detector during 2016–2018. The measurements are performed in the leptonic decay modes and , where ℓ , ℓ ′ = e , . Differential fiducial cross sections as functions of the invariant masses of the jet and charged lepton pairs, as we

A bstract Results are reported for the $$ {\mathrm{B}}_{\mathrm{s}}^0 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>B</mml:mi> <mml:mi>s</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> → μ + μ − branching fraction and effective lifetime and from a search for the decay B 0 → μ + μ − . The analysis uses a data sample of proton-proton collisions accumulated by the CMS experiment in 2011, 2012, and 2016, with center-of-mass energies (integrated luminositie

Differential Higgs boson (H) production cross sections are sensitive probes for physics beyond the standard model. New physics may contribute in the gluon-gluon fusion loop, the dominant Higgs boson production mechanism at the LHC, and manifest itself through deviations from the distributions predicted by the standard model. Combined spectra for the H → γ γ , H → Z Z , and H → b b ‾ decay channels and the inclusive Higgs boson production cross section are presented, based on proton-proton collis

The transverse momentum ( p T ) spectra of inclusively produced Λ c + baryons are measured via the exclusive decay channel Λ c + → p K − π + using the CMS detector at the LHC. Spectra are measured as a function of transverse momentum in proton-proton ( p p ) and lead-lead (PbPb) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The measurement is performed within the Λ c + rapidity interval | y | < 1 in the p T range of 5–20 GeV/ c in p p and 10–20 GeV/ c in PbPb collisions. The

A search for leptoquarks produced singly and in pairs in proton-proton collisions is presented. We consider the leptoquark (LQ) to be a scalar particle of charge −1/3 e coupling to a top quark plus a tau lepton ( t τ ) or a bottom quark plus a neutrino ( b ν ), or a vector particle of charge +2/3 e , coupling to t ν or b τ . These choices are motivated by models that can explain a series of anomalies observed in the measurement of B meson decays. In this analysis the signatures t τ ν b and t τ ν

Abstract Production cross sections of the Higgs boson are measured in the $${\mathrm{H}} \rightarrow {\mathrm{Z}} {\mathrm{Z}} \rightarrow 4\ell $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>H</mml:mi> <mml:mo>→</mml:mo> <mml:mi>Z</mml:mi> <mml:mi>Z</mml:mi> <mml:mo>→</mml:mo> <mml:mn>4</mml:mn> <mml:mi>ℓ</mml:mi> </mml:mrow> </mml:math> ( $$\ell ={\mathrm{e}},{{{\upmu }}_{\mathrm{}}^{\mathrm{}}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:

The results of a previous search by the CMS Collaboration for squarks and gluinos are reinterpreted to constrain models of leptoquark (LQ) production. The search considers jets in association with a transverse momentum imbalance, using the ${M}_{\mathrm{T}2}$ variable. The analysis uses proton-proton collision data at $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$, recorded with the CMS detector at the LHC in 2016 and corresponding to an integrated luminosity of $35.9\text{ }\text{ }{\mathrm{fb}}^{\e

Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B→D^{(*)}τν, hints of lepton universality violation in B→K^{(*)}ℓℓ decays, and the anomalous magnetic moment of the muon, can be explained by the existence of leptoquarks (LQs) with large couplings to third-generation quarks and masses at the TeV scale. The existence of these states can be probed at the LHC in high energy proton-proton collisions. A novel search is presented for pair pr

A search for the pair production of first-generation scalar leptoquarks is performed using proton-proton collision data recorded at 13 TeV center-of-mass energy with the CMS detector at the LHC. The data correspond to an integrated luminosity of 35.9 fb -1 . The leptoquarks are assumed to decay promptly to a quark and either an electron or a neutrino, with branching fractions and 1 -, respectively. The search targets the decay final states comprising two electrons, or one electron and large miss