This prospective cohort study is aimed to investigate circadian variations in corneal parameters, focusing on sleep-deprived subjects. Sixty-four healthy individuals (age range: 21-76 years) actively participated in this study, undergoing examinations at least five times within a 24-hour timeframe. The analysis encompassed keratometric parameters of the cornea's front (F) and back (B) surfaces, refractive power in flattest and steepest axes (K1, K2), astigmatism (Astig) and its axis (Axis), aspheric coefficient (Asph), corneal pachymetry values of thinnest corneal thickness (Pachy Min) and corneal thickness in the center of the pupil (Pachy Pupil), volume relative to the 3 and 10 mm corneal diagonal (Vol D3, Vol D10) and surface variance index (ISV).
View Article and Find Full Text PDFUsing proton-proton collision data corresponding to an integrated luminosity of collected by the CMS experiment at , the decay is observed for the first time, with a statistical significance exceeding 5 standard deviations. The relative branching fraction, with respect to the decay, is measured to be , where the first uncertainty is statistical, the second is systematic, and the third is related to the uncertainties in and .
View Article and Find Full Text PDFComput Softw Big Sci
September 2024
Eur Phys J C Part Fields
May 2024
A search for exotic decays of the Higgs boson () with a mass of 125 to a pair of light pseudoscalars is performed in final states where one pseudoscalar decays to two quarks and the other to a pair of muons or leptons. A data sample of proton-proton collisions at corresponding to an integrated luminosity of 138 recorded with the CMS detector is analyzed. No statistically significant excess is observed over the standard model backgrounds.
View Article and Find Full Text PDFA search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138 fb^{-1} of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016-2018. No significant excess over the predicted backgrounds is observed.
View Article and Find Full Text PDFThe first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018.
View Article and Find Full Text PDFFreshwater lakes in most inhabited areas of the world are threatened by water quality issues. Standard water conservation measures have shown efficiency in the past; however, polluted lakes have only partially recovered from eutrophication. Our knowledge is still incomplete about the sensitivity of these lakes to different anthropogenic sources and to the changes in their internal processes due to global warming.
View Article and Find Full Text PDFThe mass of the top quark is measured in 36.3 of LHC proton-proton collision data collected with the CMS detector at . The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state.
View Article and Find Full Text PDFA search for decays to invisible particles of Higgs bosons produced in association with a top-antitop quark pair or a vector boson, which both decay to a fully hadronic final state, has been performed using proton-proton collision data collected at by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138. The 95% confidence level upper limit set on the branching fraction of the 125 Higgs boson to invisible particles, , is 0.54 (0.
View Article and Find Full Text PDFMultijet events at large transverse momentum () are measured at using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of . The multiplicity of jets with that are produced in association with a high- dijet system is measured in various ranges of the of the jet with the highest transverse momentum and as a function of the azimuthal angle difference between the two highest jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest jets.
View Article and Find Full Text PDFEur Phys J C Part Fields
August 2023
The production of Z bosons associated with jets is measured in collisions at with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3. The multiplicity of jets with transverse momentum is measured for different regions of the Z boson's , from lower than 10 to higher than 100.
View Article and Find Full Text PDFProduction cross sections of the standard model Higgs boson decaying to a pair of W bosons are measured in proton-proton collisions at a center-of-mass energy of 13. The analysis targets Higgs bosons produced via gluon fusion, vector boson fusion, and in association with a W or Z boson. Candidate events are required to have at least two charged leptons and moderate missing transverse momentum, targeting events with at least one leptonically decaying W boson originating from the Higgs boson.
View Article and Find Full Text PDFThe double differential cross sections of the Drell-Yan lepton pair (, dielectron or dimuon) production are measured as functions of the invariant mass , transverse momentum , and . The observable, derived from angular measurements of the leptons and highly correlated with , is used to probe the low- region in a complementary way. Dilepton masses up to 1 are investigated.
View Article and Find Full Text PDFEur Phys J C Part Fields
July 2023
New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia 8 event generator, are obtained based on the default CMS pythia 8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies and 13, and by the CDF experiment at 1.96 are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously.
View Article and Find Full Text PDFA measurement of the jet mass distribution in hadronic decays of Lorentz-boosted top quarks is presented. The measurement is performed in the lepton + jets channel of top quark pair production () events, where the lepton is an electron or muon. The products of the hadronic top quark decay are reconstructed using a single large-radius jet with transverse momentum greater than 400.
View Article and Find Full Text PDFEur Phys J C Part Fields
July 2023
A search is reported for pairs of light Higgs bosons () produced in supersymmetric cascade decays in final states with small missing transverse momentum. A data set of LHC collisions collected with the CMS detector at and corresponding to an integrated luminosity of 138 is used. The search targets events where both bosons decay into pairs that are reconstructed as large-radius jets using substructure techniques.
View Article and Find Full Text PDFEur Phys J C Part Fields
December 2022
Measurements of the associated production of a W boson and a charm ( ) quark in proton-proton collisions at a centre-of-mass energy of 8 are reported. The analysis uses a data sample corresponding to a total integrated luminosity of 19.7 collected by the CMS detector at the LHC.
View Article and Find Full Text PDFUsing a data sample of proton-proton collisions collected by the CMS experiment at the LHC in 2017 and 2018 with an integrated luminosity of , the and decays are observed with significances exceeding 5 standard deviations. The resulting branching fraction ratios, measured for the first time, correspond to and , where the last uncertainty in the first ratio is related to the uncertainty in the ratio of production cross sections of and mesons, .
View Article and Find Full Text PDFA search for low-mass dilepton resonances in Higgs boson decays is conducted in the four-lepton final state. The decay is assumed to proceed via a pair of beyond the standard model particles, or one such particle and a boson. The search uses proton-proton collision data collected with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 137 , at a center-of-mass energy .
View Article and Find Full Text PDFEur Phys J C Part Fields
March 2022
A search for dark matter in the form of strongly interacting massive particles (SIMPs) using the CMS detector at the LHC is presented. The SIMPs would be produced in pairs that manifest themselves as pairs of jets without tracks. The energy fraction of jets carried by charged particles is used as a key discriminator to suppress efficiently the large multijet background, and the remaining background is estimated directly from data.
View Article and Find Full Text PDFEur Phys J C Part Fields
February 2022
A search for new long-lived particles decaying to leptons using proton-proton collision data produced by the CERN LHC at is presented. Events are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10 and are not required to form a common vertex.
View Article and Find Full Text PDFThe 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^{-}.
View Article and Find Full Text PDFEur Phys J C Part Fields
November 2021
A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 at the CERN LHC, corresponding to an integrated luminosity of 137 collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented.
View Article and Find Full Text PDFEur Phys J C Part Fields
September 2021
The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton-proton collisions at in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a relative precision of 1.3 and 1.
View Article and Find Full Text PDFEur Phys J C Part Fields
August 2021
A search is presented for a heavy vector resonance decaying into a boson and the standard model Higgs boson, where the boson is identified through its leptonic decays to electrons, muons, or neutrinos, and the Higgs boson is identified through its hadronic decays. The search is performed in a Lorentz-boosted regime and is based on data collected from 2016 to 2018 at the CERN LHC, corresponding to an integrated luminosity of 137 . Upper limits are derived on the production of a narrow heavy resonance , and a mass below 3.
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