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Observation of Forward Neutron Multiplicity Dependence of Dimuon Acoplanarity in Ultraperipheral Pb-Pb Collisions at sNN=5.02 TeV
(2021)Physical Review LettersThe first measurement of the dependence of γγ→μ+μ− production on the multiplicity of neutrons emitted very close to the beam direction in ultraperipheral heavy ion collisions is reported. Data for lead-lead interactions at √sNN=5.02 TeV, with an integrated luminosity of approximately 1.5 nb−1, are collected using the CMS detector at the LHC. The azimuthal correlations between the two muons in the invariant mass region 8<mμμ<60 GeV are ...Journal Article -
Measurement of the Higgs boson width and evidence of its off-shell contributions to ZZ production
(2022)Nature PhysicsSince the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width-related to its lifetime-is an important parameter. One way to determine this quantity is to measure its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here we report evidence for such ...Journal Article -
Observation of a New Excited Beauty Strange Baryon Decaying to Ξ−bπ+π−
(2021)Physical Review LettersThe Ξb-π+π- invariant mass spectrum is investigated with an event sample of proton-proton collisions at s=13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140 fb-1. The ground state Ξb- is reconstructed via its decays to J/ψΞ- and J/ψΛK-. A narrow resonance, labeled Ξb(6100)-, is observed at a Ξb-π+π- invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξb-) MeV, where the last ...Journal Article -
Measurement of the Wγ Production Cross Section in Proton-Proton Collisions at √s=13 TeV and Constraints on Effective Field Theory Coefficients
(2021)Physical Review LettersA fiducial cross section for Wγ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb-1 of data collected using the CMS detector at the LHC. The W→eν and μν decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum ...Journal Article -
Development and validation of HERWIG 7 tunes from CMS underlying-event measurements
(2021)The European Physical Journal CThis paper presents new sets of parameters (“tunes”) for the underlying-event model of the HERWIG7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in HERWIG7, and are obtained from a fit to minimum-bias data collected by the CMS experiment at s=0.9, 7, and 13Te. The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set ...Journal Article -
Measurement of the associated production of a Z boson with charm or bottom quark jets in proton-proton collisions at root s=13 TeV
(2020)Physical Review DRatios of cross sections, sigma(Z + c jets)/sigma(Z + jets), sigma(Z + b jets)/sigma(Z + jets), and sigma(Z + c jets)/sigma(Z + b jets) in the associated production of a Z boson with at least one charm or bottom quark jet are measured in proton-proton collisions at root s = 13 TeV. The data sample, collected by the CMS experiment at the CERN LHC, corresponds to an integrated luminosity of 35.9 fb(-1), with a fiducial volume of p(T) > 30 ...Journal Article -
Search for resonant pair production of Higgs bosons in the bbZZ channel in proton-proton collisions at √s=13 TeV
(2020)Physical Review DA search for the production of a narrow-width resonance decaying into a pair of Higgs bosons decaying into the bbZZ channel is presented. The analysis is based on data collected with the CMS detector during 2016, in proton-proton collisions at the LHC, corresponding to an integrated luminosity of 35.9 fb(-1). The final states considered are the ones where one of the Z bosons decays into a pair of muons or electrons, and the other Z boson ...Journal Article -
Measurement of differential t t ¯ production cross sections using top quarks at large transverse momenta in pp collisions at s =13 TeV
(2021)Physical Review DA measurement is reported of differential top quark pair (tt¯) production cross sections, where top quarks are produced at large transverse momenta. The data collected with the CMS detector at the LHC are from pp collisions at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 35.9 fb-1. The measurement uses events where at least one top quark decays as t→Wb→qq¯′b and is reconstructed as a large-radius jet with ...Journal Article -
Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at √ s =13 TeV
(2022)Physical Review LettersA search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138 fb^{-1}. No deviation from the background-only hypothesis is observed. A 95% confidence level upper limit on the Higgs ...Journal Article -
Measurement of the CP-violating phase ϕs in the Bs0→J/ψϕ(1020)→μ+μ− K+K− channel in proton-proton collisions at s=13TeV
(2021)Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy PhysicsThe CP -violating weak phase ϕs and the decay width difference ΔΓs between the light and heavy Bs0 mass eigenstates are measured with the CMS detector at the LHC in a sample of 48500 reconstructed Bs0→J/ψϕ(1020)→μ+μ−K+K− events. The measurement is based on a data sample corresponding to an integrated luminosity of 96.4fb−1, collected in proton-proton collisions at s=13TeV in 2017–2018. To extract the values of ϕs and ΔΓs, a time-dependent ...Journal Article