Vincent Lemaı̂tre

The version 3.0 of the DELPHES fast-simulation is presented. The goal of DELPHES is to allow the simulation of a multipurpose detector for phenomenological studies. The simulation includes a track propagation system embedded in a magnetic field, electromagnetic and hadron calorimeters, and a muon identification system. Physics objects that can be used for data analysis are then reconstructed from the simulated detector response. These include tracks and calorimeter deposits and high level objects such as isolated electrons, jets, taus, and missing energy. The new modular approach allows for greater flexibility in the design of the simulation and reconstruction sequence. New features such as the particle-flow reconstruction approach, crucial in the first years of the LHC, and pile-up simulation and mitigation, which is needed for the simulation of the LHC detectors in the near future, have also been implemented. The DELPHES framework is not meant to be used for advanced detector studies, for which more accurate tools are needed. Although some aspects of DELPHES are hadron collider specific, it is flexible enough to be adapted to the needs of electron-positron collider experiments.

CMS is a general purpose experiment, designed to study the physics of pp collisions at 14 TeV at the Large Hadron Collider (LHC). It currently involves more than 2000 physicists from more than 150 institutes and 37 countries. The LHC will provide extraordinary opportunities for particle physics based on its unprecedented collision energy and luminosity when it begins operation in 2007.

Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center-of-mass energies of 0.9, 2.36, and 7 TeV are presented, using data collected with the CMS detector over a broad range of pseudorapidity (η) and azimuthal angle (ϕ). Short-range correlations in Δη, which are studied in minimum bias events, are characterized using a simple “independent cluster” parametrization in order to quantify their strength (cluster size) and their extent in η (cluster decay width). Long-range azimuthal correlations are studied differentially as a function of charged particle multiplicity and particle transverse momentum using a 980 nb−1 data set at 7 TeV. In high multiplicity events, a pronounced structure emerges in the two-dimensional correlation function for particle pairs with intermediate p T of 1–3 GeV/c, 2.0 < |Δη| < 4.8 and Δϕ ≈ 0. This is the first observation of such a long-range, near-side feature in two-particle correlation functions in pp or $$ p\overline p $$ collisions.

Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 6.7 inverse microbarns. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching. The observed effect extends from the lower cut-off used in this study (jet transverse momentum = 120 GeV/c) up to the statistical limit of the available data sample (jet transverse momentum approximately 210 GeV/c). Correlations of charged particle tracks with jets indicate that the momentum imbalance is accompanied by a softening of the fragmentation pattern of the second most energetic, away-side jet. The dijet momentum balance is recovered when integrating low transverse momentum particles distributed over a wide angular range relative to the direction of the away-side jet.

Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at sqrt(s) = 7 TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit-pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity, dN(charged)/d(eta), for |eta| &lt; 0.5, of 5.78 +/- 0.01 (stat) +/- 0.23 (syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from sqrt(s) = 0.9 to 7 TeV is 66.1% +/- 1.0% (stat) +/- 4.2% (syst). The mean transverse momentum is measured to be 0.545 +/- 0.005 (stat) +/- 0.015 (syst) GeV/c. The results are compared with similar measurements at lower energies.

Measurements of inclusive charged-hadron transverse-momentum and pseudorapidity distributions are presented for proton-proton collisions at sqrt(s) = 0.9 and 2.36 TeV. The data were collected with the CMS detector during the LHC commissioning in December 2009. For non-single-diffractive interactions, the average charged-hadron transverse momentum is measured to be 0.46 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 0.9 TeV and 0.50 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 2.36 TeV, for pseudorapidities between -2.4 and +2.4. At these energies, the measured pseudorapidity densities in the central region, dN(charged)/d(eta) for |eta| < 0.5, are 3.48 +/- 0.02 (stat.) +/- 0.13 (syst.) and 4.47 +/- 0.04 (stat.) +/- 0.16 (syst.), respectively. The results at 0.9 TeV are in agreement with previous measurements and confirm the expectation of near equal hadron production in p-pbar and pp collisions. The results at 2.36 TeV represent the highest-energy measurements at a particle collider to date.

Cellular functions within tissues are strictly regulated by the tissue microenvironment which comprises extracellular matrix and extracellular matrix-deposited factors such as growth factors, cytokines and chemokines. These molecules are metabolized by matrix metalloproteinases (MMP), a disintegrin and metalloproteinases (ADAM) and ADAM with thrombospondin motifs (ADAMTS), which are members of the metzincin superfamily. They function in various pathological conditions of both neoplastic and non-neoplastic diseases by digesting different substrates under the control of tissue inhibitors of metalloproteinases (TIMP) and reversion-inducing, cysteine-rich protein with Kazal motifs (RECK). In neoplastic diseases MMP play a central role in cancer cell invasion and metastases, and ADAM are also important to cancer cell proliferation and progression through the metabolism of growth factors and their receptors. Numerous papers have described the involvement of these metalloproteinases in non-neoplastic diseases in nearly every organ. In contrast to the numerous review articles on their roles in cancer cell proliferation and progression, there are very few articles discussing non-neoplastic diseases. This review therefore will focus on the properties of MMP, ADAM and ADAMTS and their implications for non-neoplastic diseases of the cardiovascular system, respiratory system, central nervous system, digestive system, renal system, wound healing and infection, and joints and muscular system.

A search for invisible decays of a Higgs boson is performed using proton-proton collision data collected with the CMS detector at the LHC in 2016 at a center-of-mass energy , corresponding to an integrated luminosity of 35.9. The search targets the production of a Higgs boson via vector boson fusion. The data are found to be in agreement with the background contributions from standard model processes. An observed (expected) upper limit of 0.33 (0.25), at 95% confidence level, is placed on the branching fraction of the Higgs boson decay to invisible particles, assuming standard model production rates and a Higgs boson mass of 125.09 GeV. Results from a combination of this analysis and other direct searches for invisible decays of the Higgs boson, performed using data collected at , 8, and 13 TeV, are presented. An observed (expected) upper limit of 0.19 (0.15), at 95% confidence level, is set on the branching fraction of invisible decays of the Higgs boson. The combined limit represents the most stringent bound on the invisible branching fraction of the Higgs boson reported to date. This result is also interpreted in the context of Higgs-portal dark matter models, in which upper bounds are placed on the spin-independent dark-matter-nucleon scattering cross section.

For Gaia DR2 (GDR2), 280 million spectra, collected by the RVS instrument on-board Gaia, were processed and median radial velocities were derived for 9.8 million sources brighter than Grvs = 12 mag. This paper describes the validation and properties of the median radial velocities published in GDR2. Quality tests and filters are applied to select, from the 9.8 million radial velocities, those with the quality to be published in GDR2. The accuracy of the selected sample is assessed with respect to ground-based catalogues. Its precision is estimated using both ground-based catalogues and the distribution of the Gaia radial velocity uncertainties. GDR2 contains median radial velocities for 7 224 631 stars, with Teff in the range [3550, 6900] K, which passed succesfully the quality tests. The published median radial velocities provide a full sky-coverage and have a completness with respect to the astrometric data of 77.2\% (for $G \leq 12.5$ mag). The median radial velocity residuals with respect to the ground-based surveys vary from one catalogue to another, but do not exceed a few 100s m/s. In addition, the Gaia radial velocities show a positive trend as a function of magnitude, which starts around Grvs $\sim 9$ mag and reaches about $+500$ m/s at Grvs $= 11.75$ mag. The overall precision, estimated from the median of the Gaia radial velocity uncertainties, is 1.05 km/s. The radial velocity precision is function of many parameters, in particular the magnitude and effective temperature. For bright stars, Grvs in [4, 8] mag, the precision is in the range 200-350 m/s, which is about 3 to 5 times more precise than the pre-launch specification of 1 km/s. At the faint end, Grvs = 11.75 mag, the precisions for Teff = 5000 K and 6500 K are respectively 1.4 km/s and 3.7 km/s.

The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton-proton collisions at s=13TeV 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 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 fb-1 in 2015 and 2016, with a relative precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.

Gaia Data Release 3 (Gaia DR3) contains the second release of the combined radial velocities. It is based on the spectra collected during the first 34 months of the nominal mission. The longer time baseline and the improvements of the pipeline made it possible to push the processing limit, from Grvs = 12 in Gaia DR2, to Grvs = 14 mag. In this article, we describe the new functionalities implemented for Gaia DR3, the quality filters applied during processing and post-processing and the properties and performance of the published velocities. For Gaia DR3, several functionalities were upgraded or added. (Abridged) Gaia DR3 contains the combined radial velocities of 33 812 183 stars. With respect to Gaia DR2, the interval of temperature has been expanded from Teff \in [3600, 6750] K to Teff \in [3100, 14500] K for the bright stars ( Grvs \leq 12 mag) and [3100, 6750] K for the fainter stars. The radial velocities sample a significant part of the Milky Way: they reach a few kilo-parsecs beyond the Galactic centre in the disc and up to about 10-15 kpc vertically into the inner halo. The median formal precision of the velocities is of 1.3 km/s at Grvs = 12 and 6.4 km/s at Grvs = 14 mag. The velocity zero point exhibits a small systematic trend with magnitude starting around Grvs = 11 mag and reaching about 400 m/s at Grvs = 14 mag. A correction formula is provided, which can be applied to the published data. The Gaia DR3 velocity scale is in satisfactory agreement with APOGEE, GALAH, GES and RAVE, with systematic differences that mostly do not exceed a few hundreds m/s. The properties of the radial velocities are also illustrated with specific objects: open clusters, globular clusters as well as the Large Magellanic Cloud (LMC). For example, the precision of the data allows to map the line-of-sight rotational velocities of the globular cluster 47 Tuc and of the LMC.

Evidence for Higgs boson decay to a pair of muons is presented. This result combines searches in four exclusive categories targeting the production of the Higgs boson via gluon fusion, via vector boson fusion, in association with a vector boson, and in association with a top quark-antiquark pair. The analysis is performed using proton-proton collision data at $\sqrt{s} =$ 13 TeV, corresponding to an integrated luminosity of 137 fb$^{-1}$, recorded by the CMS experiment at the CERN LHC. An excess of events over the background expectation is observed in data with a significance of 3.0 standard deviations, where the expectation for the standard model (SM) Higgs boson with mass of 125.38 GeV is 2.5. The combination of this result with that from data recorded at $\sqrt{s} =$ 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.7 fb$^{-1}$, respectively, increases both the expected and observed significances by 1%. The measured signal strength, relative to the SM prediction, is 1.19 $^{+0.40}_{-0.39}$ (stat) $^{+0.15}_{-0.14}$ (syst). This result constitutes the first evidence for the decay of the Higgs boson to second generation fermions and is the most precise measurement of the Higgs boson coupling to muons reported to date.

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 $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV are also presented. Innovative techniques are used to reconstruct the electron and photon signals in the detector and to optimize the energy resolution. Events with electrons and photons in the final state are used to measure the energy resolution and energy scale uncertainty in the recorded events. The measured energy resolution for electrons produced in Z boson decays in proton-proton collision data ranges from 2 to 5%, depending on electron pseudorapidity and energy loss through bremsstrahlung in the detector material. The energy scale in the same range of energies is measured with an uncertainty smaller than 0.1 (0.3)% in the barrel (endcap) region in proton-proton collisions and better than 1 (3)% in the barrel (endcap) region in heavy ion collisions. The timing resolution for electrons from Z boson decays with the full 2016-2018 proton-proton collision data set is measured to be 200 ps.

A bstract A search is presented for physics beyond the standard model (SM) using electron or muon pairs with high invariant mass. A data set of proton-proton collisions collected by the CMS experiment at the LHC 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 from 2016 to 2018 corresponding to a total integrated luminosity of up to 140 fb − 1 is analyzed. No significant deviation is observed with respect to the SM background expectations. Upper limits are presented on the ratio of the product of the production cross section and the branching fraction to dileptons of a new narrow resonance to that of the Z boson. These provide the most stringent lower limits to date on the masses for various spin-1 particles, spin-2 gravitons in the Randall-Sundrum model, as well as spin-1 mediators between the SM and dark matter particles. Lower limits on the ultraviolet cutoff parameter are set both for four-fermion contact interactions and for the Arkani-Hamed, Dimopoulos, and Dvali model with large extra dimensions. Lepton flavor universality is tested at the TeV scale for the first time by comparing the dimuon and dielectron mass spectra. No significant deviation from the SM expectation of unity is observed.

Measurements are presented of the Bs0→μ+μ− branching fraction and effective lifetime, as well as results of a search for the B0→μ+μ− decay in proton-proton collisions at s=13TeV at the LHC. The analysis is based on data collected with the CMS detector in 2016–2018 corresponding to an integrated luminosity of 140fb−1. The branching fraction of the Bs0→μ+μ− decay and the effective Bs0 meson lifetime are the most precise single measurements to date. No evidence for the B0→μ+μ− decay has been found. All results are found to be consistent with the standard model predictions and previous measurements.

A new experimental apparatus, designed principally for a high sensitivity search for νμ → ντ oscillation, has been successlly constructed and made operational by the CHORUS Collaboration for the CERN-WA95 experiment. It consists of a large emulsion target, a scintillating fiber tracker system with optoelectronics read-out, an air-core magnet, a set of trigger hodoscopes, a calorimeter based on the lead/scintillating-fiber technique, and a muon spectrometer. The design, construction and performance of the entire apparatus and of the different detectors are described.

Matrix metalloproteinase-1 (MMP-1), or interstitial collagenase, has been hypothesized to contribute to the progression of the human atherosclerotic lesions by digesting the fibrillar collagens of the neointimal ECM. The apolipoprotein E knockout (apoE0) mouse model develops complex atherosclerotic lesions, but mice do not possess a homologue for MMP-1. To provide an in vivo evaluation of the role of MMP-1 in atherogenesis, we created a transgenic mouse model that expresses this enzyme specifically in the macrophage, under the control of the scavenger receptor A (SCAV) enhancer/promoter. The MMP-1 transgenic mice were crossed into the apoE0 background and fed an atherogenic diet for 16-25 weeks. Surprisingly, the transgenic mice demonstrated decreased lesion size compared with control littermates. The lesions of the transgenic animals were less extensive and immature, with fewer cellular layers and a diminished content of fibrillar collagen. There was no evidence of plaque rupture. Our data suggest that remodeling of the neointimal extracellular matrix by MMP-1 is beneficial in the progression of lesions.

A measurement of inclusive W and Z production cross sections in pp collisions at $ \sqrt {s} = 7 $ TeV is presented. The electron and muon decay channels are analyzed in a data sample collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb−1. The measured inclusive cross sections are σ(pp → WX) × $ \mathcal{B}\left( {{\text{W}} \to \ell \nu } \right) $ = 10.31 ± 0.02 (stat.) ± 0.09 (syst.) ± 0.10 (th.) ± 0.41 (lumi.) nb and σ(pp → ZX) × $ \mathcal{B}\left( {{\text{Z}} \to {\ell^{+} }{\ell^{-} }} \right) $ = 0.974 ± 0.007 (stat.) ± 0.007 (syst.) ± 0.018 (th.) ± 0.039 (lumi.) nb, limited to the dilepton invariant mass range 60 to 120 GeV. The luminosity-independent cross section ratios are (σ(pp → WX) × $ \mathcal{B}\left( {{\text{W}} \to \ell \nu } \right) $ /(σ(pp → ZX) × $ \mathcal{B}\left( {{\text{Z}} \to {\ell^{+} }{\ell^{-} }} \right) $ = 10.54 ± 0.07 (stat.) ± 0.08 (syst.) ± 0.16 (th.) and (σ(pp → W+ X) × $ \mathcal{B}\left( {{{\text{W}}^{ + }} \to {\ell^{+} }\nu } \right) $ /(σ(pp → W− X) × $ \mathcal{B}\left( {{{\text{W}}^{-} } \to {\ell^{-} }\bar{\nu }} \right) $ = 1.421 ± 0.006 (stat.) ± 0.014 (syst.) ± 0.029 (th.). The measured values agree with next-to-next-to-leading order QCD cross section calculations based on recent parton distribution functions.

A comparison of the relative yields of Υ resonances in the μ(+)μ(-) decay channel in Pb-Pb and pp collisions at a center-of-mass energy per nucleon pair of 2.76 TeV is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the Υ(2S) and Υ(3S) excited states to the Υ(1S) ground state in Pb-Pb and pp collisions, [Υ(2S+3S)/Υ(1S)](Pb-Pb)/[Υ(2S+3S)/Υ(1S)](pp), is found to be 0.31(-0.15)(+0.19)(stat)±0.03(syst). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1%.

We report final results on electroweak parameters from muon-neutrino electron scattering observed in the CHARM II detector from 1987 till 1991. In total 2677±82 and 2752±88 neutrino-electron scattering events have been detected in the ν and ν-beam, respectively. From the ration of differential cross sections we obtain for the electroweak mixing angle sin2 Θ = 0.2324±0.0083. From the absolute neutrino-electron scattering event rate we determined the effective vector and axial-vector neutral current coupling constants to be gVve = -0.035±0.017 and gAve = -0.503±0.017.

Matrix metalloproteinases (MMPs) are key modulators of many biological processes during pathophysiological events, such as skeletal formation, angiogenesis, cellular migration, inflammation, wound healing, coagulation, lung and cardiovascular diseases, arthritis, and cancer. Twenty-four members of the MMP family have been identified in humans, degrading many components of the extracellular matrix, cellular receptors, and cytokines. This review describes the molecular structure, activation and inhibition, and substrate specificity of MMPs, and their biological function in development and disease. Birth Defects Research (Part C) 78:1–10, 2006. © 2006 Wiley-Liss, Inc.

The hadronic final states observed with the ALEPH detector at LEP in e + e -annihilation are analysed using 730 pb -1 of data collected between 91 and 209 GeV in the framework of QCD.In particular event-shape variables and inclusive charged particle spectra are measured.The energy evolution of quantities derived from these measurements is compared to analytic QCD predictions.The mean charged particle multiplicity, the charged particle momentum spectrum and its peak position are compared to predictions of the modified-leading-logarithmic approximation.The strong coupling constant αs is determined from a fit of the QCD prediction to distributions of six event-shape variables at eight centre-of-mass energies.A study of non-perturbative power law corrections is presented.

The strongest constraint on Vtb presently comes from the 3×3 unitarity of the CKM matrix, which fixes Vtb to be very close to one. If unitarity is relaxed, current information from top production at Tevatron still leaves open the possibility that Vtb is sizably smaller than one. In minimal extensions of the standard model with extra heavy quarks, the unitarity constraints are much weaker, and the EW precision parameters entail the strongest bounds on Vtb. We discuss the experimental perspectives of discovering and identifying such new physics models at the Tevatron and the LHC, through a precise measurement of Vtb from the single top cross sections and by the study of processes where the extra heavy quarks are produced.

A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of $2.9\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ collected by the CMS experiment at the Large Hadron Collider. Upper limits at the 95% confidence level are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% confidence level: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and ${E}_{6}$ diquarks, in specific mass intervals. This extends previously published limits on these models.

The inclusive jet cross section is measured in pp collisions with a center-of-mass energy of 7 TeV at the LHC using the CMS experiment. The data sample corresponds to an integrated luminosity of 34 inverse picobarns. The measurement is made for jet transverse momenta in the range 18-1100 GeV and for absolute values of rapidity less than 3. The measured cross section extends to the highest values of jet pT ever observed and, within the experimental and theoretical uncertainties, is generally in agreement with next-to-leading-order perturbative QCD predictions.

Large cohort studies suggest that high convective volumes associated with online hemodiafiltration may reduce the risk of mortality/morbidity compared to optimal high-flux hemodialysis. By contrast, intradialytic tolerance is not well studied. The aim of the FRENCHIE (French Convective versus Hemodialysis in Elderly) study was to compare high-flux hemodialysis and online hemodiafiltration in terms of intradialytic tolerance. In this prospective, open-label randomized controlled trial, 381 elderly chronic hemodialysis patients (over age 65) were randomly assigned in a one-to-one ratio to either high-flux hemodialysis or online hemodiafiltration. The primary outcome was intradialytic tolerance (day 30–day 120). Secondary outcomes included health-related quality of life, cardiovascular risk biomarkers, morbidity, and mortality. During the observational period for intradialytic tolerance, 85% and 84% of patients in high-flux hemodialysis and online hemodiafiltration arms, respectively, experienced at least one adverse event without significant difference between groups. As exploratory analysis, intradialytic tolerance was also studied, considering the sessions as a statistical unit according to treatment actually received. Over a total of 11,981 sessions, 2,935 were complicated by the occurrence of at least one adverse event, with a significantly lower occurrence in online hemodiafiltration with fewer episodes of intradialytic symptomatic hypotension and muscle cramps. By contrast, health-related quality of life, morbidity, and mortality were not different in both groups. An improvement in the control of metabolic bone disease biomarkers and β2-microglobulin level without change in serum albumin concentration was observed with online hemodiafiltration. Thus, overall outcomes favor online hemodiafiltration over high-flux hemodialysis in the elderly. Large cohort studies suggest that high convective volumes associated with online hemodiafiltration may reduce the risk of mortality/morbidity compared to optimal high-flux hemodialysis. By contrast, intradialytic tolerance is not well studied. The aim of the FRENCHIE (French Convective versus Hemodialysis in Elderly) study was to compare high-flux hemodialysis and online hemodiafiltration in terms of intradialytic tolerance. In this prospective, open-label randomized controlled trial, 381 elderly chronic hemodialysis patients (over age 65) were randomly assigned in a one-to-one ratio to either high-flux hemodialysis or online hemodiafiltration. The primary outcome was intradialytic tolerance (day 30–day 120). Secondary outcomes included health-related quality of life, cardiovascular risk biomarkers, morbidity, and mortality. During the observational period for intradialytic tolerance, 85% and 84% of patients in high-flux hemodialysis and online hemodiafiltration arms, respectively, experienced at least one adverse event without significant difference between groups. As exploratory analysis, intradialytic tolerance was also studied, considering the sessions as a statistical unit according to treatment actually received. Over a total of 11,981 sessions, 2,935 were complicated by the occurrence of at least one adverse event, with a significantly lower occurrence in online hemodiafiltration with fewer episodes of intradialytic symptomatic hypotension and muscle cramps. By contrast, health-related quality of life, morbidity, and mortality were not different in both groups. An improvement in the control of metabolic bone disease biomarkers and β2-microglobulin level without change in serum albumin concentration was observed with online hemodiafiltration. Thus, overall outcomes favor online hemodiafiltration over high-flux hemodialysis in the elderly. Renal replacement therapy (RRT) by diffusive-based hemodialysis (HD) is still hampered by intradialytic adverse events1Bradshaw W. Bennett P.N. Asymptomatic Intradialytic Hypotension: The Need for Pre-Emptive Intervention.Nephrol Nurs J. 2015; 42: 479-485PubMed Google Scholar, 2Kuipers J. Oosterhuis J. Krijnen W. et al.Prevalence of intradialytic hypotension, clinical symptoms and nursing interventions - a three-months, prospective study of 3818 haemodialysis sessions.BMC Nephrol. 2016; 17: 21Crossref PubMed Scopus (34) Google Scholar and relatively poor outcomes for end-stage kidney disease (ESKD) patients.3Flythe J. Xue H. Lynch K. et al.Association of mortality risk with various definitions of intradialytic hypotension.J Am Soc Nephrol. 2015; 26: 724-734Crossref PubMed Scopus (247) Google Scholar, 4Stefánsson B. Brunelli S. 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Toz H. et al.Mortality and cardiovascular events in online haemodiafiltration (OL-HDF) compared with high-flux dialysis: results from the Turkish OL-HDF Study.Nephrol Dial Transplant. 2013; 28: 192-202Crossref PubMed Scopus (333) Google Scholar, 14Mercadal L. Franck J.E. Metzger M. et al.Hemodiafiltration versus hemodialysis and survival in patients with ESRD: the French Renal Epidemiology and Information Network (REIN) registry.Am J Kidney Dis. 2016; 68: 247-255Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar, 15Peters S.A. Bots M.L. Canaud B. et al.Haemodiafiltration and mortality in end-stage kidney disease patients: a pooled individual participant data analysis from four randomized controlled trials.Nephrol Dial Transplant. 2016; 31: 978-984Crossref PubMed Scopus (152) Google Scholar Whereas most large, retrospective or prospective randomized controlled trials have investigated the benefits of convective-based modalities on objectively measured end points (e.g., mortality), few studies have reported patient-perceived symptomatology related to dialysis sessions, demonstrating little or no advantage with OLHDF. In a randomized controlled trial, Locatelli et al.16Locatelli F. Mastrangelo F. Redaelli B. et al.Effects of different membranes and dialysis technologies on patient treatment tolerance and nutritional parameters. The Italian Cooperative Dialysis Study Group.Kidney Int. 1996; 50: 1293-1302Abstract Full Text PDF PubMed Scopus (265) Google Scholar reported a significant reduction in clinical symptomatic IDH incidence using OLHDF, but failed to show any improvement in subjective patient perception. More recently, Caplin et al.17Caplin B. Alston H. Davenport A. Does online haemodiafiltration reduce intra-dialytic patient symptoms?.Nephron Clin Pract. 2013; 124: 184-190Crossref PubMed Scopus (15) Google Scholar also yielded no evidence that switching prevalent stable ESKD patients from high-flux HD (HFHD) to hemodiafiltration (HDF) greatly improved perceived intradialytic symptomatology. In addition, most studies have explored the effects of HDF versus HFHD in a relatively selective population that does not reflect the aging and comorbidity profile of today’s ESKD population.18Goodkin D. Bragg-Gresham J. Koenig K. et al.Association of comorbid conditions and mortality in hemodialysis patients in Europe, Japan, and the United States: the Dialysis Outcomes and Practice Patterns Study (DOPPS).J Am Soc Nephrol. 2003; 14: 3270-3277Crossref PubMed Scopus (628) Google Scholar, 19Prabhavalkar S. Verghis R. McNamee P. et al.Four decades of chronic haemodialysis: lessons from the past and implications for the future.Nephron Clin Pract. 2012; 121: c54-c59Crossref PubMed Scopus (2) Google Scholar In the FRENCHIE (French Convective versus Hemodialysis in Elderly) study, we aimed to explore the potential benefits of using OLHDF versus optimal HFHD in elderly ESKD patients. The primary objective was to focus on treatment tolerance, and secondary objectives were to analyze patient-reported outcome measures, intermediary outcomes (biomarkers of cardiovascular risk and nutritional status), and objectively measured outcomes (hospitalizations and mortality). Between May 2005 and May 2011, 415 ESKD patients ≥65 years old were assessed for eligibility in 32 French dialysis facilities. Thirty-four patients were excluded: 5 did not meet inclusion criteria, 12 declined to participate, and 17 were excluded for other reasons. A total of 381 patients were randomized and followed up until their final visit no later than May 2013 (Figure 1). The mean ± SD and median (interquartile range) duration of follow-up were 19.65 ± 7.38 months and 23.92 (6.44) months. Patient characteristics at baseline (both the randomized and primary outcome analysis populations) are summarized in Table 1 and did not significantly differ between study arms.Table 1Baseline characteristicsVariableRandomized populationPopulation of primary outcome analysisHigh-flux HD(n = 191)OLHDF(n = 190)High-flux HD(n = 152)OLHDF(n = 151)Gender, male (n [%])115 (60.21)114 (60.00)93 (61.18)90 (59.60)Age (yr)76.11 (± 6.68)76.35 (± 6.13)76.41 (± 6.79)76.61 (± 5.86)BMI (kg/m2)26.26 (± 4.68)26.27 (± 5.11)26.26 (± 4.65)26.29 (± 5.18)BMI ≥ 30 kg/m2 (n [%])37 (21.39)34 (19.65)31 (21.09)29 (19.73)Etiology of ESRD (n [%]) Vascular and hypertensive nephropathy82 (43.62)90 (48.13)70 (46.05)74 (49.01) Glomerulonephritis34 (18.09)28 (14.97)32 (21.05)22 (14.57) Diabetic nephropathy58 (30.85)53 (28.34)41 (26.97)42 (27.81) Cystic renal disease11 (5.85)13 (6.95)9 (5.92)10 (6.62) Interstitial nephropathy18 (9.57)20 (10.70)15 (9.87)16 (10.60) Other cause28 (14.89)32 (17.11)21 (13.82)29 (19.21)Diabetes mellitus (n [%])73 (38.42)74 (39.36)56 (36.84)63 (41.72)Hypertension (n [%])135 (71.05)149 (79.26)110 (72.37)121 (80.13)Cardiopathy disease history (n [%])97 (51.05)99 (52.66)82 (53.95)80 (52.98)Arteriopathy disease history (n [%])83 (43.68)77 (40.96)72 (47.37)63 (41.72)Dialysis vintage (yr)4.63 (± 5.04)5.00 (± 5.88)4.76 (± 5.41)4.93 (± 6.20)Vascular access, arteriovenous fistula (n [%])130 (68.06)131 (68.95)130 (85.53)131 (86.75)Antihypertensive medication (n [%])101 (53.44)106 (56.99)73 (48.34)82 (54.30) ACE inhibitors and ARBs48 (25.40)53 (28.49)33 (21.85)37 (24.50) Beta blockers60 (31.75)56 (30.11)38 (25.17)40 (26.49) Calcium channel blockers34 (17.99)41 (22.04)24 (15.89)31 (20.53)Erythropoietin stimulating agents (IU/kg/wk)104.66 (± 107.80)120.76 (± 134.28)104.58 (± 108.09)121.79 (± 143.40)Hemoglobin (g/dl)11.59 (± 1.25)11.63 (± 1.35)11.69 (± 1.24)11.64 (± 1.41)C reactive protein (mg/l)11.51 (± 23.36)12.11 (± 16.20)10.06 (± 14.10)11.64 (± 14.90)Albumin (g/l)39.06 (± 3.76)38.93 (± 4.14)39.01 (± 3.65)38.62 (± 4.08)Transthyretin (g/l)0.25 (± 0.06)0.25 (± 0.06)0.25 (± 0.06)0.24 (± 0.07)β2-microglobulin (mg/l)27.75 (± 7.97)26.08 (± 6.69)27.50 (± 7.40)26.07 (± 6.99)Total cholesterol (mmol/l)4.55 (± 1.12)4.42 (± 1.15)4.59 (± 1.13)4.42 (± 1.21)LDL cholesterol (mmol/l)2.64 (± 0.96)2.52 (± 0.95)2.67 (± 0.98)2.52 (± 0.97)ACE, angiotensin-converting enzyme; ARB, angiotensin receptor blockers; BMI, body mass index; ESRD, end-stage renal disease; HD, hemodialysis; LDL, low-density lipoprotein; OLHDF, online hemodiafiltration.Values are described by proportions for categorical variables and mean (± SD) for quantitative variables. Open table in a new tab ACE, angiotensin-converting enzyme; ARB, angiotensin receptor blockers; BMI, body mass index; ESRD, end-stage renal disease; HD, hemodialysis; LDL, low-density lipoprotein; OLHDF, online hemodiafiltration. Values are described by proportions for categorical variables and mean (± SD) for quantitative variables. HD treatment parameters from the first session (0 months) in allocated treatment to the last session (24 months) of the study are presented in Table 2. In the OLHDF group, throughout the study duration, the percentage of patients receiving pre-dilution and related infusions was less than 10% (8.38%, 9.09%, 7.10%, and 8.27% at 0, 6, 12, and 24 months, respectively). At 0 months, the 2 groups did not significantly differ regarding all dialysis prescriptions and treatment schedule except for dialysate flow and convection volume, which were significantly higher in the OLHDF group. Dialysate flow increased significantly in both groups throughout follow-up without no significant variation between groups (P = 0.07). In addition, a significant increase in blood flow and urea single-pool Kt/V during follow-up was observed in the OLHDF group, whereas no significant variation was reported in the HFHD group. When modeling urea single-pool Kt/V according to time, group, and time × group, and after adjustment for blood and dialysate flow rate, no dramatic change in P values was observed. The slight dialysis duration differences observed between groups might be attributable to sampling fluctuations, or minor errors in connection and disconnection timing reported in patient logs. However, these minor differences should not translate to any effect on dialysis modality, as they did not reach significance.Table 2Characteristics of treatment according to the HFHD and OLHDF groups during follow-upVariable0 moMean (± SD)6 moMean (± SD)12 moMean (± SD)24 moMean (± SD)TimeP valueGroupP valueTime × groupP valueDuration of dialysis session (h)0.300.840.26 HFHD3.95 (± 0.36)3.93 (± 0.33)3.94 (± 0.36)3.91 (± 0.34)0.48 OLHDF3.91 (± 0.48)3.92 (± 0.49)3.98 (± 0.56)3.98 (± 0.60)0.17 P valueaP value of group effect at each time point.0.340.370.960.32Blood flow (ml/min)0.020.050.08 HFHD335.32 (± 42.15)336.28 (± 42.23)336.73 (± 39.73)334.90 (± 41.56)0.97 OLHDF337.54 (± 41.63)341.22 (± 43.44)344.68 (± 41.08)349.51 (± 40.46)<0.01 P valueaP value of group effect at each time point.0.580.140.06<0.01Dialysate flow (ml/min)<0.01<0.00010.07 HFHD509.09 (± 46.06)510.08 (± 61.53)517.30 (± 56.70)523.81 (± 66.55)0.04 OLHDF539.29 (± 76.04)560.79 (± 101.62)553.90 (± 98.75)552.05 (± 104.53)<0.01 P valueaP value of group effect at each time point.<0.0001<0.0001<0.0001<0.01Intradialytic weight change (pre-post) (kg)0.200.920.86 HFHD2.14 (± 0.81)2.22 (± 0.83)2.11 (± 0.93)2.12 (± 0.86)0.29 OLHDF2.10 (± 0.82)2.21 (± 0.94)2.14 (± 0.91)2.18 (± 0.94)0.64 P valueaP value of group effect at each time point.0.760.650.930.63Ultrafiltration rate (ml/h/kg)0.170.460.90 HFHD7.91 (± 3.09)8.15 (± 3.05)7.72 (± 3.30)7.93 (± 3.32)0.40 OLHDF7.99 (± 3.32)8.32 (± 3.30)7.96 (± 3.57)8.35 (± 4.03)0.43 P valueaP value of group effect at each time point.0.770.760.550.33Urea single-pool Kt/V<0.01<0.0010.18 HFHD1.56 (± 0.36)1.54 (± 0.27)1.54 (± 0.31)1.59 (± 0.36)0.46 OLHDF1.62 (± 0.32)1.62 (± 0.38)1.69 (± 0.38)1.74 (± 0.35)<0.001 P valueaP value of group effect at each time point.0.120.13<0.01<0.01nPCR (g/kg/d)0.170.690.22 HFHD1.25 (± 0.33)1.23 (± 0.34)1.19 (± 0.33)1.21 (± 0.38)0.32 OLHDF1.25 (± 0.34)1.18 (± 0.38)1.23 (± 0.38)1.24 (± 0.39)0.12 P valueaP value of group effect at each time point.0.600.320.290.57Convection volume (l/session)0.0012<0.00010.0005 HFHD1.99 (± 1.22)2.11 (± 1.17)1.94 (± 1.17)2.00 (± 1.22)0.99 OLHDFbAfter correction for mode of dilution.2019.32 (± 4.46)20.95 (± 5.30)21.93 (± 5.21)22.53 (± 6.76)<0.0001 post-dilution infusion19.86 (± 4.68)20.76 (± 4.88)21.75 (± 4.91)22.48 (±6.26) pre-dilution & related infusion37.58 (± 7.32)42.62 (± 13.35)44.08 (± 10.88)42.59 (± 16.38) P valueaP value of group effect at each time point.<0.0001<0.0001<0.0001<0.0001Erythropoietin stimulating agents (IU/kg/wk)0.080.290.11 HFHD104.66 (± 107.80)90.42 (± 87.18)95.39 (± 87.39)80.57 (± 70.40)0.63 OLHDF120.76 (± 134.28)92.65 (± 84.43)109.77 (± 117.12)110.66 (± 99.77)0.01 P valueaP value of group effect at each time point.0.140.600.360.14HFHD, high-flux hemodialysis; mo, months; OLHDF, online hemodiafiltration. P < 0.05 are in bold.a P value of group effect at each time point.b After correction for mode of dilution.20Canaud B. Levesque R. Krieter D. et al.On-line hemodiafiltration as routine treatment of end-stage renal failure: why pre- or mixed dilution mode is necessary in on-line hemodiafiltration today?.Blood Purif. 2004; 22: 40-48Crossref PubMed Scopus (36) Google Scholar Open table in a new tab HFHD, high-flux hemodialysis; mo, months; OLHDF, online hemodiafiltration. P < 0.05 are in bold. Records of intradialytic events started at day 30 after the stabilization period. Only 2 patients were switched during this interval: 1 moved to another dialysis center not performing HDF, and the other refused HDF treatment due to nonspecific discomfort and intolerance to the cooling effect of the method. The main intent-to-treat analysis of intradialytic tolerance was performed in 152 and 151 patients in the HFHD and OLHDF groups, respectively (Table 3). During the observational period from day 30 to day 120, 84.9% and 84.1% of patients in the HFHD and OLHDF arms, respectively, experienced at least 1 adverse event, with no significant difference between groups (odds ratio [OR] = 0.94, confidence interval [CI] 95% = [0.51–1.76], P = 0.85).Table 3Primary outcomes: intent-to-treat analysis of intradialytic tolerance and patient-reported outcomes between the HFHD and OLHDF groupsVariableHFHD(N = 152)OLHDF(N = 151)Odds ratio(CI 95%)P valueYule’s Qn%n%At least 1 eventNo2315.132415.8910.85Yes12984.8712784.110.94 [0.51;1.76]–0.03Asymptomatic hypotensionNo4932.245033.1110.87Yes10367.7610166.890.96 [0.59;1.55]–0.02Symptomatic hypotensionNo10971.7111878.1510.20Yes4328.293321.850.71 [0.42;1.20]–0.17HeadacheNo13991.4513992.0510.85Yes138.55127.950.92 [0.41;2.09]–0.04Muscle crampsNo10065.7911374.8310.09Yes5234.213825.170.65 [0.39;1.06]–0.21NauseaNo13991.4513086.0910.14Yes138.552113.911.73 [0.83;3.59]0.27VomitingNo14092.1114394.7010.37Yes127.8985.300.65 [0.26;1.65]–0.21FeverNo14796.7114696.6910.99Yes53.2953.311.01 [0.29;3.55]0.005Chest painNo15199.3414696.6910.14Yes10.6653.315.17 [0.60;44.8]0.68ArrhythmiaNo14998.0314193.3810.06Yes31.97106.623.52 [0.95;13.1]0.56Other eventNo8153.298254.3010.86Yes7146.716945.700.96 [0.61;1.51]–0.02HFHD, high-flux hemodialysis; OLHDF, online hemodiafiltration.Intent-to-treat analysis of intradialytic tolerance was performed based on the percentage of patients presenting with at least 1 adverse event occurring between day 30 and day 120 of follow-up. Open table in a new tab HFHD, high-flux hemodialysis; OLHDF, online hemodiafiltration. Intent-to-treat analysis of intradialytic tolerance was performed based on the percentage of patients presenting with at least 1 adverse event occurring between day 30 and day 120 of follow-up. As an exploratory analysis of the root cause of intradialytic intolerance, intradialytic tolerance was examined, considering the sessions as a statistical unit according to treatment actually received. The median number of dialysis sessions per month was 13.34 [10.05–14.50] in the HFHD group and 13.34 [10.15–15.05] in the OLHDF group (P = 0.93). Analysis was performed on a total of 6077 HFHD sessions and 5904 OLHDF sessions. Of 11,981 sessions, 2935 (24.5%) were complicated by the occurrence of at least 1 adverse event, with a lower occurrence in OLHDF (23.1%; P = 0.0004) (Table 4). Compared with HFHD sessions, OLHDF sessions presented fewer episodes of asymptomatic hypotension (P = 0.002) and muscle cramps (P = 0.03). More arrhythmia episodes were reported in OLHDF sessions (P = 0.01), but the occurrence remained relatively low in both treatments (0.5‰ vs. 2.4‰ in HFHD and OLHDF sessions, respectively) compared with previous studies. No significant difference between HFHD and OLHDF sessions was evidenced in terms of headache, nausea, fever reaction (temperature > 39°C not bacterial [catheter or other]-related), or chest pain.Table 4Exploratory root cause analysis: intradialytic tolerance and patient-reported outcomes between the HFHD and OLHDF groups using sessions as a statistical unitVariableHFHD(N = 6077)OLHDF(N = 5904)Odds Ratio(CI 95%)P valuen%n%At least 1 eventNo450574.13454176.9110.0004Yes157225.87136323.090.86 [0.79; 0.94]Asymptomatic hypotensionNo482479.38481981.6210.002Yes125320.62108518.380.87 [0.79; 0.95]Symptomatic hypotensionNo597298.27582298.6110.13Yes1051.73821.390.80 [0.60; 1.07]HeadacheNo605499.62588699.7010.49Yes230.38180.300.81 [0.43; 1.49]Muscle crampsNo594497.81580798.3610.03Yes1332.19971.640.75 [0.57; 0.97]NauseaNo605699.65587799.5410.33Yes210.35270.461.32 [0.75; 2.34]VomitingNo605599.64589399.8110.07Yes220.36110.190.51 [0.25; 1.06]FeverNo607299.92589999.9210.96Yes50.0850.081.03 [0.30; 3.56]Chest painNo607699.98589899.9010.09Yes10.0260.106.18 [0.74; 51.3]ArrhythmiaNo607499.95589099.7610.01Yes30.05140.244.81 [1.38; 16.8]Other eventNo588396.81574297.2610.15Yes1943.191622.745.16 [1.76; 15.1]HFHD, high-flux hemodialysis; OLHDF, online hemodiafiltration.Analysis of intradialytic tolerance according to actual treatment received at each session was performed based on the presence of at least one adverse event per session occurring between day 30 and day 120 of follow-up. P < 0.05 are in bold. Open table in a new tab HFHD, high-flux hemodialysis; OLHDF, online hemodiafiltration. Analysis of intradialytic tolerance according to actual treatment received at each session was performed based on the presence of at least one adverse event per session occurring between day 30 and day 120 of follow-up. P < 0.05 are in bold. At 0 months, the 2 groups did not differ for all health-related quality of life (HRQOL) component scores studied: burden of kidney disease (P = 0.07), physical composite score (P = 0.78), and mental composite score (P = 0.73). No difference in evolution over the follow-up was observed between the HFHD and OLHDF groups except for mental composite score (P = 0.04), which tended to be higher in the HFHD group at 24 months (P = 0.06) (Supplementary Figure S1). Treatment adequacy is summarized in Table 5 and Figure 2. At 0 months, the 2 groups were comparable for all parameters of dialysis adequacy. In both arms, a slight but significant decrease in post-dialysis body weight was observed during follow-up. However, after taking into account group and time effects, the reported variation did not reach significance (P = 0.08). Significantly lower pre-dialysis β2-microglobulin (β2m) level (P < 0.01) and higher β2m reduction rate (P < 0.0001) were observed in the OLHDF group over time (Figure 2). These differences remained significant over the 24-month follow-up, but no difference in variation was observed between the 2 groups. In the OLHDF arm, pre-dialysis phosphate level significantly decreased throughout the study (P < 0.001) compared with the HFHD arm, and the variation between the 2 groups was significant (P = 0.01). All other parameters including dialysis adequacy and iron status parameters did not differ between the groups during the study.Table 5Treatment adequacy according to the HFHD and OLHDF groups during follow-upVariable0 moMean (± SD)6 moMean (± SD)12 moMean (± SD)24 moMean (± SD)TimeP valueGroupP valueTime × groupP valueSystolic blood pressure (mm Hg)0.490.640.18 HFHD137.63 (± 23.63)137.57 (± 24.26)135.63 (± 23.37)140.48 (± 23.08)0.21 OLHDF138.56 (± 21.84)137.91 (± 24.96)136.33 (± 23.68)134.92 (± 24.20)0.43 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.730.840.870.06Diastolic blood pressure (mm Hg)0.280.140.50 HFHD65.75 (± 14.12)64.40 (± 15.80)63.99 (± 15.71)65.77 (± 15.64)0.54 OLHDF64.53 (± 15.09)62.91 (± 14.48)62.95 (± 15.51)61.27 (± 13.38)0.26 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.460.430.680.04Heart rate (bits/min)0.320.410.30 HFHD74.50 (± 12.43)72.34 (± 11.93)72.72 (± 12.20)72.18 (± 12.10)0.31 OLHDF74.40 (± 13.26)74.39 (± 14.76)73.36 (± 12.91)75.07 (± 15.15)0.30 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.850.240.920.20Post-dialysis body weight (kg)<.00010.380.08 HFHD70.78 (± 14.44)70.67 (± 14.04)70.60 (± 14.05)70.16 (± 14.22)<.0001 OLHDF69.86 (± 14.49)69.40 (± 14.12)69.40 (± 14.34)68.80 (± 13.47)<.0001 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.580.360.240.44Pre-dialysis sodium (mmol/l)0.070.580.28 HFHD138.16 (± 3.35)138.14 (± 3.26)137.96 (± 3.16)138.23 (± 3.36)0.83 OLHDF138.37 (± 3.44)137.73 (± 3.59)138.08 (± 3.41)138.08 (± 3.62)0.02 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.590.190.760.54Pre-dialysis potassium (mmol/l)0.160.770.40 HFHD4.87 (± 0.71)4.90 (± 0.63)4.84 (± 0.59)4.87 (± 0.67)0.87 OLHDF4.80 (± 0.64)4.93 (± 0.73)4.84 (± 0.67)4.78 (± 0.76)0.07 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.330.470.810.43Pre-dialysis bicarbonate (mmol/l)0.450.560.95 HFHD23.06 (± 2.77)22.93 (± 2.64)23.08 (± 2.92)22.85 (± 2.42)0.54 OLHDF22.88 (± 3.10)22.81 (± 3.32)23.06 (± 2.61)22.90 (± 2.96)0.84 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.510.620.540.99Pre-dialysis calcium (mmol/l)0.540.840.48 HFHD2.22 (± 0.17)2.21 (± 0.16)2.23 (± 0.20)2.20 (± 0.19)0.63 OLHDF2.23 (± 0.17)2.21 (± 0.16)2.21 (± 0.17)2.21 (± 0.17)0.40 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.540.720.290.78Pre-dialysis hemoglobin (g/dl)0.950.740.62 HFHD11.59 (± 1.25)11.64 (± 1.37)11.56 (± 1.25)11.69 (± 1.12)0.76 OLHDF11.63 (± 1.35)11.54 (± 1.38)11.59 (± 1.20)11.55 (± 1.48)0.81 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.740.500.710.43Pre-dialysis TSAT (%)0.010.370.64 HFHD28.87 (± 11.84)29.00 (± 13.02)28.45 (± 12.35)27.60 (± 11.56)0.56 OLHDF28.56 (± 12.37)28.26 (± 12.76)27.54 (± 13.37)25.82 (± 12.05)0.01 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.950.730.700.14Pre-dialysis ferritin (ng/ml)0.030.450.51 HFHD463.43 (± 514.43)468.42 (± 455.85)533.31 (± 850.66)483.66 (± 299.08)0.64 OLHDF488.84 (± 695.23)527.39 (± 693.32)468.16 (± 705.69)537.95 (± 489.90)0.02 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.850.950.780.12Pre-dialysis PTH (pg/ml)0.500.350.79 HFHD289.03 (± 355.70)280.96 (± 275.04)283.00 (± 294.68)283.53 (± 250.96)0.76 OLHDF263.39 (± 263.32)264.08 (± 256.24)262.01 (± 258.33)241.74 (± 210.52)0.51 P valueaP value of group effect at each time point. P < 0.05 are in bold.0.820.530.300.26HFHD, high-flux hemodialysis; mo, months; OLHDF, online hemodiafiltration; PTH, parathyroid hormone; TSAT, transferrin saturation.a P value of group effect at each time point.P < 0.05 are in bold. Open table in a new tab HFHD, high-flux hemodialysis; mo, months; OLHDF, online hemodiafiltration; PTH, parathyroid hormone; TSAT, transferrin saturation. The variation of nutritional, inflammatory, and cardiovascular biomarkers in the 2 groups are summarized in Table 6 and Figure 3. At 0 months, the 2 groups were comparable for all these parameters. Albumin remained stable in both study arms over time, while a significant decrease in transthyretin was observed but only in the HFHD group (P < 0.01). We observed a slight but not significant increase over time in C-reactive protein (CRP) level, comparable in both groups (Figure 3). In addition, interleukin (IL) 6, tumor necrosis factor alpha, and IL-10 remained stable throughout follow-up. N-terminal pro b-type natriuretic peptide and cardiac troponin T increased significantly in both groups over time, but no significant variation was observed between groups.Table 6Biological variables over time in patie

The first LHC pp collisions at centre-of-mass energies of 0.9 and 2.36 TeV were recorded by the CMS detector in December 2009. The trajectories of charged particles produced in the collisions were reconstructed using the all-silicon Tracker and their momenta were measured in the 3.8 T axial magnetic field. Results from the Tracker commissioning are presented including studies of timing, efficiency, signal-to-noise, resolution, and ionization energy. Reconstructed tracks are used to benchmark the performance in terms of track and vertex resolutions, reconstruction of decays, estimation of ionization energy loss, as well as identification of photon conversions, nuclear interactions, and heavy-flavour decays.

Measurements of primary charged hadron multiplicity distributions are presented for non-single-diffractive events in proton-proton collisions at centre-of-mass energies of $ \sqrt {s} = 0.9 $ , 2.36, and 7 TeV, in five pseudorapidity ranges from |η| < 0.5 to |η| < 2.4. The data were collected with the minimum-bias trigger of the CMS experiment during the LHC commissioning runs in 2009 and the 7 TeV run in 2010. The multiplicity distribution at $ \sqrt {s} = 0.9\;{\text{TeV}} $ is in agreement with previous measurements. At higher energies the increase of the mean multiplicity with $ \sqrt {s} $ is underestimated by most event generators. The average transverse momentum as a function of the multiplicity is also presented. The measurement of higher-order moments of the multiplicity distribution confirms the violation of Koba-Nielsen-Olesen scaling that has been observed at lower energies.

The Gaia Data Release 2 contains the 1st release of radial velocities complementing the kinematic data of a sample of about 7 million relatively bright, late-type stars. Aims: This paper provides a detailed description of the Gaia spectroscopic data processing pipeline, and of the approach adopted to derive the radial velocities presented in DR2. Methods: The pipeline must perform four main tasks: (i) clean and reduce the spectra observed with the Radial Velocity Spectrometer (RVS); (ii) calibrate the RVS instrument, including wavelength, straylight, line-spread function, bias non-uniformity, and photometric zeropoint; (iii) extract the radial velocities; and (iv) verify the accuracy and precision of the results. The radial velocity of a star is obtained through a fit of the RVS spectrum relative to an appropriate synthetic template spectrum. An additional task of the spectroscopic pipeline was to provide 1st-order estimates of the stellar atmospheric parameters required to select such template spectra. We describe the pipeline features and present the detailed calibration algorithms and software solutions we used to produce the radial velocities published in DR2. Results: The spectroscopic processing pipeline produced median radial velocities for Gaia stars with narrow-band near-IR magnitude Grvs < 12 (i.e. brighter than V~13). Stars identified as double-lined spectroscopic binaries were removed from the pipeline, while variable stars, single-lined, and non-detected double-lined spectroscopic binaries were treated as single stars. The scatter in radial velocity among different observations of a same star, also published in DR2, provides information about radial velocity variability. For the hottest (Teff > 7000 K) and coolest (Teff < 3500 K) stars, the accuracy and precision of the stellar parameter estimates are not sufficient to allow selection of appropriate templates. [Abridged]

The W+W- and ZZ production cross sections are measured in proton-proton collisions at sqrt(s) = 8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 inverse femtobarns. The measurements are performed in the leptonic decay modes W+W- to l' nu l'' nu and ZZ to 2l 2l', where l = e, mu and l'(l'') = e, mu, tau. The measured cross sections sigma(pp to W+W-) = 69.9 +/- 2.8 (stat.) +/- 5.6 (syst.) +/- 3.1 (lumi.) pb and sigma(pp to ZZ) = 8.4 +/- 1.0 (stat.) +/- 0.7 (syst.) +/- 0.4 (lumi.) pb, for both Z bosons produced in the mass region 60 < m[Z] < 120 GeV, are consistent with standard model predictions. These are the first measurements of the diboson production cross sections at sqrt(s) = 8 TeV.

The first measurement of the cross section for top-quark pair production in pp collisions at the LHC at center-of-mass energy sqrt(s)= 7 TeV has been performed using 3.1 {\pm} 0.3 inverse pb of data recorded by the CMS detector. This result utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse energy, and two or more jets. Backgrounds from Drell-Yan and non-W/Z boson production are estimated from data. Eleven events are observed in the data with 2.1 {\pm} 1.0 events expected from background. The measured cross section is 194 {\pm} 72 (stat.) {\pm} 24 (syst.) {\pm} 21 (lumi.) pb, consistent with next-to-leading order predictions.

Context. The Gaia Data Release 2 (DR2) contains the first release of radial velocities complementing the kinematic data of a sample of about 7 million relatively bright, late-type stars. Aims. This paper provides a detailed description of the Gaia spectroscopic data processing pipeline, and of the approach adopted to derive the radial velocities presented in DR2. Methods. The pipeline must perform four main tasks: (i) clean and reduce the spectra observed with the Radial Velocity Spectrometer (RVS); (ii) calibrate the RVS instrument, including wavelength, straylight, line-spread function, bias non-uniformity, and photometric zeropoint; (iii) extract the radial velocities; and (iv) verify the accuracy and precision of the results. The radial velocity of a star is obtained through a fit of the RVS spectrum relative to an appropriate synthetic template spectrum. An additional task of the spectroscopic pipeline was to provide first-order estimates of the stellar atmospheric parameters required to select such template spectra. We describe the pipeline features and present the detailed calibration algorithms and software solutions we used to produce the radial velocities published in DR2. Results. The spectroscopic processing pipeline produced median radial velocities for Gaia stars with narrow-band near-IR magnitude G RVS ≤ 12 (i.e. brighter than V ~ 13). Stars identified as double-lined spectroscopic binaries were removed from the pipeline, while variable stars, single-lined, and non-detected double-lined spectroscopic binaries were treated as single stars. The scatter in radial velocity among different observations of a same star, also published in Gaia DR2, provides information about radial velocity variability. For the hottest ( T eff ≥ 7000 K) and coolest ( T eff ≤ 3500 K) stars, the accuracy and precision of the stellar parameter estimates are not sufficient to allow selection of appropriate templates. The radial velocities obtained for these stars were removed from DR2. The pipeline also provides a first-order estimate of the performance obtained. The overall accuracy of radial velocity measurements is around ~200–300 m s −1 , and the overall precision is ~1 km s −1 ; it reaches ~200 m s −1 for the brightest stars.

At the start of Run 2 in 2015, the LHC delivered proton-proton collisions at a center-of-mass energy of 13 TeV. During Run 2 (years 2015-2018) the LHC eventually reached a luminosity of 2.1 $\times$ 10$^{34}$ cm$^{-2}$ s$^{-1}$, almost three times that reached during Run 1 (2009-2013) and a factor of two larger than the LHC design value, leading to events with up to a mean of about 50 simultaneous inelastic proton-proton collisions per bunch crossing (pileup). The CMS Level-1 trigger was upgraded prior to 2016 to improve the selection of physics events in the challenging conditions posed by the second run of the LHC. This paper describes the performance of the CMS Level-1 trigger upgrade during the data taking period of 2016-2018. The upgraded trigger implements pattern recognition and boosted decision tree regression techniques for muon reconstruction, includes pileup subtraction for jets and energy sums, and incorporates pileup-dependent isolation requirements for electrons and tau leptons. In addition, the new trigger calculates high-level quantities such as the invariant mass of pairs of reconstructed particles. The upgrade reduces the trigger rate from background processes and improves the trigger efficiency for a wide variety of physics signals.

A measurement of the underlying activity in scattering processes with a hard scale in the several GeV region is performed in proton-proton collisions at sqrt(s) = 0.9 and 7 TeV, using data collected by the CMS experiment at the LHC. The production of charged particles with pseudorapidity |eta| < 2 and transverse momentum pT > 0.5 GeV/c is studied in the azimuthal region transverse to that of the leading set of charged particles forming a track-jet. A significant growth of the average multiplicity and scalar-pT sum of the particles in the transverse region is observed with increasing pT of the leading track-jet, followed by a much slower rise above a few GeV/c. For track-jet pT larger than a few GeV/c, the activity in the transverse region is approximately doubled with a centre-of-mass energy increase from 0.9 to 7 TeV. Predictions of several QCD-inspired models as implemented in PYTHIA are compared to the data.

A search for narrow and broad resonances with masses greater than 1.8 TeV decaying to a pair of jets is presented. The search uses proton-proton collision data at $\sqrt{s} =$ 13 TeV collected at the LHC, corresponding to an integrated luminosity of 137 fb$^{-1}$. The background arising from standard model processes is predicted with the fit method used in previous publications and with a new method. The dijet invariant mass spectrum is well described by both data-driven methods, and no significant evidence for the production of new particles is observed. Model independent upper limits are reported on the production cross sections of narrow resonances, and broad resonances with widths up to 55% of the resonance mass. Limits are presented on the masses of narrow resonances from various models: string resonances, scalar diquarks, axigluons, colorons, excited quarks, color-octet scalars, W' and Z' bosons, Randall-Sundrum gravitons, and dark matter mediators. The limits on narrow resonances are improved by 200 to 800 GeV relative to those reported in previous CMS dijet resonance searches. The limits on dark matter mediators are presented as a function of the resonance mass and width, and on the associated coupling strength as a function of the mediator mass. These limits exclude at 95% confidence level a dark matter mediator with a mass of 1.8 TeV and width 1% of its mass or higher, up to one with a mass of 4.8 TeV and a width 45% of its mass or higher.

A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9 fb$^{-1}$ of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a center-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be $m_\mathrm{H} =$ 125.78 $\pm$ 0.26 GeV. This is combined with a measurement of $m_\mathrm{H}$ already performed in the H $\to$ ZZ $\to$ 4$\ell$ decay channel using the same data set, giving $m_\mathrm{H} =$ 125.46 $\pm$ 0.16 GeV. This result, when further combined with an earlier measurement of $m_\mathrm{H}$ using data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of $m_\mathrm{H} =$ 125.38 $\pm$ 0.14 GeV. This is currently the most precise measurement of the mass of the Higgs boson.

The standard model (SM) production of four top quarks ($\mathrm{t\bar{t}t\bar{t}}$) in proton-proton collision 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 fb$^{-1}$ at a center-of-mass energy of 13 TeV. The events are required to contain two same-sign charged leptons (electrons or muons) or at least three leptons, and jets. The observed and expected significances for the $\mathrm{t\bar{t}t\bar{t}}$ signal are respectively 2.6 and 2.7 standard deviations, and the $\mathrm{t\bar{t}t\bar{t}}$ cross section is measured to be 12.6 $^{+5.8}_{-5.2}$ fb. The results are used to constrain the Yukawa coupling of the top quark to the Higgs boson, $y_{\mathrm{t}}$, yielding a limit of $|y_{\mathrm{t}}$ $/$ $y_{\mathrm{t}}^{\mathrm{SM}}|$ $<$ 1.7 at 95% confidence level, where $y_{\mathrm{t}}^{\mathrm{SM}}$ is the SM value of $y_{\mathrm{t}}$. They are also used to constrain the oblique parameter of the Higgs boson in an effective field theory framework, $\hat{H}$ $<$ 0.12. Limits are set on the production of a heavy scalar or pseudoscalar boson in Type-II two-Higgs-doublet and simplified dark matter models, with exclusion limits reaching 350-470 GeV and 350-550 GeV for scalar and pseudoscalar bosons, respectively. Upper bounds are also set on couplings of the top quark to new light particles.

Results are reported from a search for supersymmetric particles in the final state with multiple jets and large missing transverse momentum. The search uses a sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV collected with the CMS detector in 2016-2018, corresponding to an integrated luminosity of 137 fb$^{-1}$, representing essentially the full LHC Run 2 data sample. The analysis is performed in a four-dimensional search region defined in terms of the number of jets, the number of tagged bottom quark jets, the scalar sum of jet transverse momenta, and the magnitude of the vector sum of jet transverse momenta. No significant excess in the event yield is observed relative to the expected background contributions from standard model processes. Limits on the pair production of gluinos and squarks are obtained in the framework of simplified models for supersymmetric particle production and decay processes. Assuming the lightest supersymmetric particle to be a neutralino, lower limits on the gluino mass as large as 2000 to 2310 GeV are obtained at 95% confidence level, while lower limits on the squark mass as large as 1190 to 1630 GeV are obtained, depending on the production scenario.

Machine-learning (ML) techniques are explored to identify and classify hadronic decays of highly Lorentz-boosted W/Z/Higgs bosons and top quarks. Techniques without ML have also been evaluated and are included for comparison. The identification performances of a variety of algorithms are characterized in simulated events and directly compared with data. The algorithms are validated using proton-proton collision data at √s = 13TeV, corresponding to an integrated luminosity of 35.9 fb−1. Systematic uncertainties are assessed by comparing the results obtained using simulation and collision data. The new techniques studied in this paper provide significant performance improvements over non-ML techniques, reducing the background rate by up to an order of magnitude at the same signal efficiency.

Signals consistent with the B+c(2S) and B*+c(2S) states are observed in proton-proton collisions at √s=13 TeV, in an event sample corresponding to an integrated luminosity of 143 fb−1, collected by the CMS experiment during the 2015–2018 LHC running periods. These excited ¯bc states are observed in the B+cπ+π− invariant mass spectrum, with the ground state B+c reconstructed through its decay to J/ψπ+. The two states are reconstructed as two well-resolved peaks, separated in mass by 29.1±1.5(stat)±0.7(syst) MeV. The observation of two peaks, rather than one, is established with a significance exceeding five standard deviations. The mass of the B+c(2S) meson is measured to be 6871.0±1.2(stat)±0.8(syst)±0.8(B+c) MeV, where the last term corresponds to the uncertainty in the world-average B+c mass.Received 1 February 2019Revised 18 February 2019DOI:https://doi.org/10.1103/PhysRevLett.122.132001Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.© 2019 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Research AreasParticle productionPhysical SystemsBottom quarkMesonsTechniquesHadron collidersParticles & Fields

Results are reported for the $$ {\mathrm{B}}_{\mathrm{s}}^0 $$→ μ+μ− branching fraction and effective lifetime and from a search for the decay B0→ 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 luminosities) of 7 TeV (5 fb−1), 8 TeV (20 fb−1), and 13 TeV (36 fb−1). The branching fractions are determined by measuring event yields relative to B+→ J/ψK+ decays (with J/ψ → μ+μ−), which results in the reduction of many of the systematic uncertainties. The decay $$ {\mathrm{B}}_{\mathrm{s}}^0 $$→ μ+μ− is observed with a significance of 5.6 standard deviations. The branching fraction is measured to be $$ \mathrm{\mathcal{B}}\left({\mathrm{B}}_{\mathrm{s}}^0\to {\upmu}^{+}{\upmu}^{-}\right)=\left[2.9\pm 0.7\left(\exp \right)\pm 0.2\left(\mathrm{frag}\right)\right]\times {10}^{-9} $$, where the first uncertainty combines the experimental statistical and systematic contributions, and the second is due to the uncertainty in the ratio of the $$ {\mathrm{B}}_{\mathrm{s}}^0 $$ and the B+ fragmentation functions. No significant excess is observed for the decay B0→ μ+μ−, and an upper limit of ℬ(B0 → μ+μ−) < 3.6 × 10−10 is obtained at 95% confidence level. The $$ {\mathrm{B}}_{\mathrm{s}}^0 $$→ μ+μ− effective lifetime is measured to be $$ {\tau}_{\upmu^{+}{\upmu}^{-}}={1.70}_{-0.44}^{+0.61} $$ ps. These results are consistent with standard model predictions.

A search is presented for a narrow resonance decaying to a pair of oppositely charged muons using $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$ 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 11.5--45 GeV mass range, the search uses data collected with dimuon triggers with low transverse momentum thresholds, recorded at high rate by storing a reduced amount of trigger-level information. The data correspond to integrated luminosities of 137 and $96.6\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ for conventional and high-rate triggering, respectively. No significant resonant peaks are observed in the probed mass ranges. The search sets the most stringent constraints to date on a dark photon in the $\ensuremath{\sim}30--75$ and 110--200 GeV mass ranges.

With increasing instantaneous luminosity at the LHC come additional reconstruction challenges. At high luminosity, many collisions occur simultaneously within one proton-proton bunch crossing. The isolation of an interesting collision from the additional "pileup" collisions is needed for effective physics performance. In the CMS Collaboration, several techniques capable of mitigating the impact of these pileup collisions have been developed. Such methods include charged-hadron subtraction, pileup jet identification, isospin-based neutral particle "$\delta\beta$" correction, and, most recently, pileup per particle identification. This paper surveys the performance of these techniques for jet and missing transverse momentum reconstruction, as well as muon isolation. The analysis makes use of data corresponding to 35.9 fb$^{-1}$ collected with the CMS experiment in 2016 at a center-of-mass energy of 13 TeV. The performance of each algorithm is discussed for up to 70 simultaneous collisions per bunch crossing. Significant improvements are found in the identification of pileup jets, the jet energy, mass, and angular resolution, missing transverse momentum resolution, and muon isolation when using pileup per particle identification.

Abstract 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 $$13\,\text {Te}\text {V} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>13</mml:mn><mml:mspace /><mml:mrow><mml:mtext>Te</mml:mtext><mml:mspace /></mml:mrow></mml:mrow></mml:math> , collected by the CMS experiment at the LHC in 2016–2018 and corresponding to an integrated luminosity of 137 $$\,\text {fb}^{-1}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mspace /><mml:msup><mml:mtext>fb</mml:mtext><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math> . 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 $$M_{\mathrm {T2}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>M</mml:mi><mml:mrow><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> for events with at least two jets. For events with exactly one jet, the transverse momentum of the jet is used instead. The second search looks in addition for disappearing tracks produced by BSM long-lived charged particles that decay within the volume of the tracking detector. No excess event yield is observed above the predicted standard model background. This is used to constrain a range of BSM models that predict the following: the pair production of gluinos and squarks in the context of supersymmetry models conserving R -parity, with or without intermediate long-lived charginos produced in the decay chain; the resonant production of a colored scalar state decaying to a massive Dirac fermion and a quark; or the pair production of scalar and vector leptoquarks each decaying to a neutrino and a top, bottom, or light-flavor quark. In most of the cases, the results obtained are the most stringent constraints to date.

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 −1/3e coupling to a top quark plus a tau lepton (tτ) or a bottom quark plus a neutrino (bν), or a vector particle of charge +2/3e, coupling to tν or bτ. 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 tτνb and tτν are probed, using data recorded by the CMS experiment at the CERN LHC at s=13 TeV and that correspond to an integrated luminosity of 137 fb−1. These signatures have not been previously explored in a dedicated search. The data are found to be in agreement with the standard model prediction. Lower limits at 95% confidence level are set on the LQ mass in the range 0.98–1.73 TeV, depending on the LQ spin and its coupling λ to a lepton and a quark, and assuming equal couplings for the two LQ decay modes considered. These are the most stringent constraints to date on the existence of leptoquarks in this scenario.

A bstract A search is presented for new particles produced at the LHC 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, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb − 1 , collected in 2017–2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb − 1 , collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.

A bstract A search for phenomena beyond the standard model in final states with two oppositely charged same-flavor leptons and missing transverse momentum is presented. The search uses a data sample of 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, corresponding to an integrated luminosity of 137 fb − 1 , collected by the CMS experiment at the LHC. Three potential signatures of physics beyond the standard model are explored: an excess of events with a lepton pair, whose invariant mass is consistent with the Z boson mass; a kinematic edge in the invariant mass distribution of the lepton pair; and the nonresonant production of two leptons. The observed event yields are consistent with those expected from standard model backgrounds. The results of the first search allow the exclusion of gluino masses up to 1870 GeV, as well as chargino (neutralino) masses up to 750 (800) GeV, while those of the searches for the other two signatures allow the exclusion of light-flavor (bottom) squark masses up to 1800 (1600) GeV and slepton masses up to 700 GeV, respectively, at 95% confidence level within certain supersymmetry scenarios.

The rate for Higgs (H) bosons production in association with either one (tH) or two ($\mathrm{t\bar{t}}$H) top quarks is measured in final states containing multiple electrons, muons, or tau leptons decaying to hadrons and a neutrino, using proton-proton collisions recorded at a center-of-mass energy of 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 137 fb$^{-1}$. The analysis is aimed at events that contain H $\to$ WW, H $\to$ $\tau\tau$, or H $\to$ ZZ decays and each of the top quark(s) decays either to lepton+jets or all-jet channels. Sensitivity to signal is maximized by including ten signatures in the analysis, depending on the lepton multiplicity. The separation among the tH, the $\mathrm{t\bar{t}}$H, and the backgrounds is enhanced through machine-learning techniques and matrix-element methods. The measured production rates for the $\mathrm{t\bar{t}}$H and tH signals correspond to 0.92 $\pm$ 0.19 (stat) $^{+0.17}_{-0.13}$ (syst) and 5.7 $\pm$ 2.7 (stat) $\pm$ 3.0 (syst) of their respective standard model (SM) expectations. The corresponding observed (expected) significance amounts to 4.7 (5.2) standard deviations for $\mathrm{t\bar{t}}$H, and to 1.4 (0.3) for tH production. Assuming that the Higgs boson coupling to the tau lepton is equal in strength to its expectation in the SM, the coupling $y_{\mathrm{t}}$ of the Higgs boson to the top quark divided by its SM expectation, $\kappa_\mathrm{t}$ = $y_\mathrm{t} / y_\mathrm{t}^\mathrm{SM}$, is constrained to be within $-$0.9 $\lt$ $\kappa_\mathrm{t}$ $\lt$ $-$0.7 or 0.7 $\lt$ $\kappa_\mathrm{t}$ $\lt$ 1.1, at 95% confidence level. This result is the most sensitive measurement of the $\mathrm{t\bar{t}}$H production rate to date.

Production cross sections of the Higgs boson are measured in the H $\to$ ZZ $\to$ $4\ell$ ($\ell$ $=$ e, $\mu$) decay channel. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137 fb$^{-1}$ is used. The signal strength modifier $\mu$, defined as the ratio of the Higgs boson production rate in the $4\ell$ channel to the standard model (SM) expectation, is measured to be $\mu$ $=$ 0.94 $\pm$ 0.07 (stat) ${}^{+0.09}_{-0.08}$ (syst) at a fixed value of $m_\mathrm{H}$ $=$ 125.38 GeV. The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the H $\to$ $4\ell$ process is measured to be 2.84 $^{+0.23}_{-0.22}$ (stat) ${}^{+0.26}_{-0.21}$ (syst) fb, which is compatible with the SM prediction of 2.84 $\pm$ 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions.

A search for invisible decays of the Higgs boson produced via vector boson fusion (VBF) has been performed with 101 fb$^{-1}$ of proton-proton collisions delivered by the LHC at $\sqrt{s} =$ 13 TeV and collected by the CMS detector in 2017 and 2018. The sensitivity to the VBF production mechanism is enhanced by constructing two analysis categories, one based on missing transverse momentum, and a second based on the properties of jets. In addition to control regions with Z and W boson candidate events, a highly populated control region, based on the production of a photon in association with jets, is used to constrain the dominant irreducible background from the invisible decay of a Z boson produced in association with jets. The results of this search are combined with all previous measurements in the VBF topology, based on data collected in 2012 (at $\sqrt{s} =$ 8 TeV), 2015, and 2016, corresponding to integrated luminosities of 19.7, 2.3, and 36.3 fb$^{-1}$, respectively. The observed (expected) upper limit on the invisible branching fraction of the Higgs boson is found to be 0.18 (0.10) at the 95% confidence level, assuming the standard model production cross section. The results are also interpreted in the context of Higgs-portal models.

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 sNN=5.02 TeV per nucleon pair, using the decay chain X(3872)→J/ψπ+π−→μ+μ−π+π−. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7 nb−1. The measurement is performed in the rapidity and transverse momentum ranges |y|<1.6 and 15<pT<50 GeV/c. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to ψ2S yield ratio is found to be ρPb−Pb=1.08±0.49(stat)±0.52(syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state.Received 25 February 2021Revised 2 September 2021Accepted 22 December 2021DOI:https://doi.org/10.1103/PhysRevLett.128.032001Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.© 2022 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Research AreasParticle & resonance productionQuark-gluon plasmaRelativistic heavy-ion collisionsTechniquesHadron collidersParticles & FieldsNuclear Physics

Gaia Data Release 3 (Gaia DR3) contains the second release of the combined radial velocities. It is based on the spectra collected during the first 34 months of the nominal mission. The longer time baseline and the improvements of the pipeline made it possible to push the processing limit, from Grvs = 12 in Gaia DR2, to Grvs = 14 mag. In this article, we describe the new functionalities implemented for Gaia DR3, the quality filters applied during processing and post-processing and the properties and performance of the published velocities. For Gaia DR3, several functionalities were upgraded or added. (Abridged) Gaia DR3 contains the combined radial velocities of 33 812 183 stars. With respect to Gaia DR2, the interval of temperature has been expanded from Teff \in [3600, 6750] K to Teff \in [3100, 14500] K for the bright stars ( Grvs \leq 12 mag) and [3100, 6750] K for the fainter stars. The radial velocities sample a significant part of the Milky Way: they reach a few kilo-parsecs beyond the Galactic centre in the disc and up to about 10-15 kpc vertically into the inner halo. The median formal precision of the velocities is of 1.3 km/s at Grvs = 12 and 6.4 km/s at Grvs = 14 mag. The velocity zero point exhibits a small systematic trend with magnitude starting around Grvs = 11 mag and reaching about 400 m/s at Grvs = 14 mag. A correction formula is provided, which can be applied to the published data. The Gaia DR3 velocity scale is in satisfactory agreement with APOGEE, GALAH, GES and RAVE, with systematic differences that mostly do not exceed a few hundreds m/s. The properties of the radial velocities are also illustrated with specific objects: open clusters, globular clusters as well as the Large Magellanic Cloud (LMC). For example, the precision of the data allows to map the line-of-sight rotational velocities of the globular cluster 47 Tuc and of the LMC.

A bstract Three searches are presented for signatures of physics beyond the standard model (SM) in ττ final states in proton-proton collisions at the LHC, using a data sample collected with the CMS detector 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, corresponding to an integrated luminosity of 138 fb − 1 . Upper limits at 95% confidence level (CL) are set on the products of the branching fraction for the decay into τ leptons and the cross sections for the production of a new boson ϕ , in addition to the H(125) boson, via gluon fusion (gg ϕ ) or in association with b quarks, ranging from $$ \mathcal{O} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>O</mml:mi> </mml:math> (10 pb) for a mass of 60 GeV to 0.3 fb for a mass of 3.5 TeV each. The data reveal two excesses for gg ϕ production with local p -values equivalent to about three standard deviations at m ϕ = 0 . 1 and 1.2 TeV. In a search for t -channel exchange of a vector leptoquark U 1 , 95% CL upper limits are set on the dimensionless U 1 leptoquark coupling to quarks and τ leptons ranging from 1 for a mass of 1 TeV to 6 for a mass of 5 TeV, depending on the scenario. In the interpretations of the $$ {M}_{\textrm{h}}^{125} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>M</mml:mi> <mml:mi>h</mml:mi> <mml:mn>125</mml:mn> </mml:msubsup> </mml:math> and $$ {M}_{\textrm{h},\textrm{EFT}}^{125} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>M</mml:mi> <mml:mrow> <mml:mi>h</mml:mi> <mml:mo>,</mml:mo> <mml:mi>EFT</mml:mi> </mml:mrow> <mml:mn>125</mml:mn> </mml:msubsup> </mml:math> minimal supersymmetric SM benchmark scenarios, additional Higgs bosons with masses below 350 GeV are excluded at 95% CL.

A search has been performed for the Standard Model Higgs boson in the data sample collected with the ALEPH detector at LEP, at centre-of-mass energies up to 209GeV. An excess of 3sigma beyond the background expectation is found, consistent with the production of the Higgs boson with a mass near 114GeV/c2. Much of this excess is seen in the four-jet analyses, where three high purity events are selected.

Rationale: Oxidants are believed to play a major role in the development of emphysema.Objectives: This study aimed to determine if the expression of human copper–zinc superoxide dismutase (CuZnSOD) within the lungs of mice protects against the development of emphysema.Methods: Transgenic CuZnSOD and littermate mice were exposed to cigarette smoke (6 h/d, 5 d/wk, for 1 yr) and compared with nonexposed mice. A second group was treated with intratracheal elastase to induce emphysema.Measurements: Lung inflammation was measured by cell counts and myeloperoxidase levels. Oxidative damage was assessed by immunofluorescence for 3-nitrotyrosine and 8-hydroxydeoxyguanosine and lipid peroxidation levels. The development of emphysema was determined by measuring the mean linear intercept (Lm).Main Results: Smoke exposure caused a fourfold increase in neutrophilic inflammation and doubled lung myeloperoxidase activity. This inflammatory response did not occur in the smoke-exposed CuZnSOD mice. Similarly, CuZnSOD expression prevented the 58% increase in lung lipid peroxidation products that occurred after smoke exposure. Most important, CuZnSOD prevented the onset of emphysema in both the smoke-induced model (Lm, 68 exposed control vs. 58 exposed transgenic; p < 0.04) and elastase-generated model (Lm, 80 exposed control vs. 63 exposed transgenic; p < 0.03). These results demonstrate for the first time that antioxidants can prevent smoke-induced inflammation and can counteract the proteolytic cascade that leads to emphysema formation in two separate animal models of the disease.Conclusions: These findings indicate that strategies aimed at enhancing or supplementing lung antioxidants could be effective for the prevention and treatment of this disease.

ROTA, S.1; MOUGENOT, B.2; BAUDOUIN, B.1; MEYER-BRASSEUR, M. DE1; LEMAITRE, V.3; MICHEL, C.4; MIGNON, F.4; RONDEAU, E.4; VANHILLE, P.3; VERROUST, P.2; RONCO, P.1,4 Author Information

The tissue inhibitor of metalloproteinases-1 (TIMP-1) is expressed in atherosclerotic lesions, where it may play a critical role in regulating the activity of matrix metalloproteinases (MMPs). Several MMPs are overexpressed in the atherosclerotic plaque, and they are believed to contribute to the expansion and rupture of the lesion.The Timp-1-knockout mouse model (Timp-1-/-) was crossed into the apolipoprotein E-knockout (apoE0) background. A study population of male apoE0 mice, half of them deficient in TIMP-1, was fed an atherogenic diet. After 10 weeks of the diet, the mean lesion sizes of the two groups of animals were not significantly different, and the average content of fibrillar collagen and macrophages in the lesions was similar. There was no sign of plaque hemorrhage, even after 22 weeks of high-fat diet, indicating that deficiency in TIMP-1 does not predispose to luminal rupture. However the atherosclerotic lesions of the Timp-1-/0 mice developed more aortic medial ruptures, in which all elastic lamellae of the media were degraded and infiltrated with macrophages, forming pseudo-microaneurysms. After 10 weeks of high-fat diet, the Timp-1-/0/apoE0 mice averaged 1.9+/-1.2 medial ruptures in the proximal aorta, compared with 0.5+/-0.7 for the apoE0 controls (P<0.003). At the site of degradation, in situ zymography revealed that the gelatinolytic activity, mainly associated with macrophages, could be abolished by the addition of MMP inhibitors.These data strongly suggest that TIMP-1 plays a key role in preventing medial degradation associated with atherosclerosis through its ability to inhibit the MMPs that are involved in the disruption of the media.

Vertebrate collagenases, matrix metalloproteinases (MMPs), cleave type I collagen at a single helical locus. We show here that rodent interstitial collagenases (MMP-13), but not human fibroblast collagenase (MMP-1), cleave type I collagen at an additional aminotelopeptide locus. Collagenase cDNAs and chimeric constructs in pET-3d, juxtaposing MMP-13 sequences amino-terminal to the active site in the catalytic domain and MMP-1 sequences carboxyl-terminal and vice versa, were expressed in Escherichia coli. Assays utilized collagen from wild type (+/+) mice or mice that carry a targeted mutation (r/r) that encodes substitutions in α1(I) chains that prevent collagenase cleavage at the helical locus. MMP-13 and chimeric molecules that contained the MMP-13 sequences amino-terminal to the active site cleaved (+/+) collagen at the helical locus and cleaved cross-linked (r/r) collagen in the aminotelopeptide (β components converted to α chains). Human MMP-1 and chimeric MMP-1/MMP-13 with MMP-1 sequences amino-terminal to the active site cleaved collagen at the helical locus but not in the aminotelopeptide. All activities were inhibited by TIMP-1, 1,10-phenanthroline, and EDTA. Sequences in the distal two-thirds of the catalytic domain determine the aminotelopeptide-degrading capacity of MMP-13.

Events containing only energetic photons are analysed in a sample of $628 \mathrm{pb}^{-1}$ of data recorded from $\rm e^+e^-$ collisions at centre-of-mass energies between 189 and 209 GeV by the ALEPH detector at LEP. The $e^+ e^-\to \nu\bar{\nu}\gamma(\gamma)$ and $e^+ e^-\to \gamma\gamma(\gamma)$ cross sections are measured and found to be in agreement with the standard model predictions. The number of light neutrino generations is determined to be $N_\nu = 2.86 \pm 0.09$ . Upper limits are derived on the cross sections for photon production in the context of several supersymmetric models. Limits are also set on the parameters of models with extra spatial dimensions, with contact interactions and with excited electrons.

Matrix metalloproteinase (MMP)-9 has been consistently identified in the lungs of patients with chronic obstructive pulmonary disease (COPD). However, its role in the development of the disease remains undefined. Mice that specifically express human MMP-9 in their macrophages were generated, and morphometric, biochemical, and histological analyses were conducted on the transgenic and littermate control mice over 1 yr to determine the effect of macrophage MMP-9 expression on emphysema formation and lung matrix content. Lung morphometry was normal in transgenic mice at 2 mo of age (mean linear intercept = 50+/-3 littermate mice vs. 51+/-2 transgenic mice). However, after 12 mo of age, the MMP-9 transgenic mice developed significant air space enlargement (mean linear intercept = 53+/-3 littermate mice vs. 61+/-2 MMP-9 transgenic mice; P<0.04). Lung hydroxyproline content was not significantly different between wild-type and transgenic mice, but MMP-9 did significantly decrease alveolar wall elastin at 1 yr of age (4.9+/-0.3% area of alveolar wall in the littermate mice vs. 3.3+/-0.3% area of alveolar wall in the MMP-9 mice; P<0.004). Thus these results establish a central role for MMP-9 in the pathogenesis of this disease by demonstrating that expression of this protease in macrophages can alter the extracellular matrix and induce progressive air space enlargement in mice.

We present the FP420 R&D project, which has been studying the key aspects of the development and installation of a silicon tracker and fast-timing detectors in the LHC tunnel at 420 m from the interaction points of the ATLAS and CMS experiments. These detectors would measure precisely very forward protons in conjunction with the corresponding central detectors as a means to study Standard Model (SM) physics, and to search for and characterise new physics signals. This report includes a detailed description of the physics case for the detector and, in particular, for the measurement of Central Exclusive Production, pp→p+ϕ+p, in which the outgoing protons remain intact and the central system ϕ may be a single particle such as a SM or MSSM Higgs boson. Other physics topics discussed are γγ and γp interactions, and diffractive processes. The report includes a detailed study of the trigger strategy, acceptance, reconstruction efficiencies, and expected yields for a particularpp→pHp measurement with Higgs boson decay in theb mode. The document also describes the detector acceptance as given by the LHC beam optics between the interaction points and the FP420 location, the machine backgrounds, the new proposed connection cryostat and the moving (``Hamburg'') beam-pipe at 420 m, and the radio-frequency impact of the design on the LHC. The last part of the document is devoted to a description of the 3D silicon sensors and associated tracking performances, the design of two fast-timing detectors capable of accurate vertex reconstruction for background rejection at high-luminosities, and the detector alignment and calibration strategy.

First measurements of dihadron correlationsfor charged particles are presented for central PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76TeV over a broad range in relative pseudorapidity (∆η) and the full range of relative azimuthal angle (∆ϕ). The data were collected with the CMS detector, at the LHC. A broadening of the away-side (∆ϕ ≈ π) azimuthal correlation is observed at all ∆η, as compared to the measurements in pp collisions. Furthermore, long-range dihadron correlations in ∆η are observed for particles with similar ϕ values. This phenomenon, also known as the “ridge”, persists up to at least |∆η| = 4. For particles with transverse momenta (p T) of2-4 GeV/c, the ridge is found to be most prominent when these particles are correlated with particles of p T = 2-6 GeV/c, and to be much reduced when paired with particles of p T = 10-12 GeV/c.

Electroweak production of the top quark is measured for the first time in pp collisions at √=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb⁻¹. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi) pb, consistent with the standard model expectation.

A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.

A search for Z bosons in the μ(+)μ(-) decay channel has been performed in PbPb collisions at √S(NN)=2.76 TeV with the CMS detector at the LHC, in a 7.2 μb(-1) data sample. The number of opposite-sign muon pairs observed in the 60-120 GeV/c(2) invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10(-8), in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.

The intermediate conductance calcium-activated potassium channel KCa3.1 contributes to a variety of cell activation processes in pathologies such as inflammation, carcinogenesis, and vascular remodeling. We examined the electrophysiological and transcriptional mechanisms by which KCa3.1 regulates vascular smooth muscle cell (VSMC) proliferation. Platelet-derived growth factor-BB (PDGF)-induced proliferation of human coronary artery VSMCs was attenuated by lowering intracellular Ca(2+) concentration ([Ca(2+)]i) and was enhanced by elevating [Ca(2+)]i. KCa3.1 blockade or knockdown inhibited proliferation by suppressing the rise in [Ca(2+)]i and attenuating the expression of phosphorylated cAMP-response element-binding protein (CREB), c-Fos, and neuron-derived orphan receptor-1 (NOR-1). This antiproliferative effect was abolished by elevating [Ca(2+)]i. KCa3.1 overexpression induced VSMC proliferation, and potentiated PDGF-induced proliferation, by inducing CREB phosphorylation, c-Fos, and NOR-1. Pharmacological stimulation of KCa3.1 unexpectedly suppressed proliferation by abolishing the expression and activity of KCa3.1 and PDGF β-receptors and inhibiting the rise in [Ca(2+)]i. The stimulation also attenuated the levels of phosphorylated CREB, c-Fos, and cyclin expression. After KCa3.1 blockade, the characteristic round shape of VSMCs expressing high l-caldesmon and low calponin-1 (dedifferentiation state) was maintained, whereas KCa3.1 stimulation induced a spindle-shaped cellular appearance, with low l-caldesmon and high calponin-1. In conclusion, KCa3.1 plays an important role in VSMC proliferation via controlling Ca(2+)-dependent signaling pathways, and its modulation may therefore constitute a new therapeutic target for cell proliferative diseases such as atherosclerosis.

Smoking is a major risk factor for heart disease, but the molecular effects of cigarette smoke on vascular cells are poorly understood. In this study, we demonstrate that matrix metalloproteinase-1 (MMP-1), a collagenase expressed in atherosclerosis and aneurysms but not in the normal vessel wall, is induced in the aortic endothelium of rabbits exposed to cigarette smoke. In vitro cigarette smoke extract (CSE) and one of its components, acrolein, inhibit the mammalian target of rapamycin (mTOR)/p70S6K pathway in human endothelial cells, and chemical inhibition of this pathway by rapamycin resulted in elevated MMP-1. Moreover, the tissue inhibitor of metalloproteases-3 (TIMP-3), a major regulator of angiogenesis, is significantly downregulated in aortic endothelial cells treated with CSE, acrolein, or rapamycin. These data indicate that inhibition of mTOR by cigarette smoke components is a key event in the modulation of endothelial MMP-1 and TIMP-3 expression. Our study suggests that circulating smoke components, including acrolein, contribute to vascular diseases through enhanced MMP-1 and decreased TIMP-3 secretion in the endothelium, potentially leading to impaired angiogenesis, matrix disruption, and vessel injury.

A search for microscopic black hole production and decay in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 pb−1. Events with large total transverse energy are analyzed for the presence of multiple high-energy jets, leptons, and photons, typical of a signal expected from a microscopic black hole. Good agreement with the standard model backgrounds, dominated by QCD multijet production, is observed for various final-state multiplicities and model-independent limits on new physics in these final states are set. Using simple semi-classical approximation, limits on the minimum black hole mass are derived as well, in the range 3.5–4.5 TeV. These are the first direct limits on black hole production at a particle accelerator.

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E(T)(γ) in pp collisions at √s=7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9 pb(-1). Photons are required to have a pseudorapidity |η(γ)|<1.45 and E(T)(γ)>21 GeV, covering the kinematic region 0.006<x(T)<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.

A search is presented for long-lived charged particles that decay within the volume of the silicon tracker of the CMS experiment. Such particles can produce events with an isolated track that is missing hits in the outermost layers of the silicon tracker, and is also associated with little energy deposited in the calorimeters and no hits in the muon detectors. The search for events with this "disappearing track" signature is performed in a sample of proton-proton collisions recorded by the CMS experiment at the LHC with a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 101fb−1 recorded in 2017 and 2018. The observation of 48 events is consistent with the estimated background of 47.8−2.3+2.7(stat)±8.1(syst) events. Upper limits are set on chargino production in the context of an anomaly-mediated supersymmetry breaking model for purely wino and higgsino neutralino scenarios. At 95% confidence level, the first constraint is placed on chargino masses in the higgsino case, excluding below 750 (175) GeV for a lifetime of 3 (0.05) ns. In the wino case, the results of this search are combined with a previous CMS search to produce a result representing the complete LHC data set recorded in 2015–2018, the most stringent constraints to date. At 95% confidence level, chargino masses in the wino case are excluded below 884 (474) GeV for a lifetime of 3 (0.2) ns.

Normalised multi-differential cross sections for top quark pair ($\mathrm{t\overline{t}}$) production are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV using events containing two oppositely charged leptons. The analysed data were recorded with the CMS detector in 2016 and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The double-differential $\mathrm{t\overline{t}}$ cross section is measured as a function of the kinematic properties of the top quark and of the $\mathrm{t\overline{t}}$ system at parton level in the full phase space. A triple-differential measurement is performed as a function of the invariant mass and rapidity of the $\mathrm{t\overline{t}}$ system and the multiplicity of additional jets at particle level. The data are compared to predictions of Monte Carlo event generators that complement next-to-leading-order (NLO) quantum chromodynamics (QCD) calculations with parton showers. Together with a fixed-order NLO QCD calculation, the triple-differential measurement is used to extract values of the strong coupling strength $\alpha_S$ and the top quark pole mass ($m_\mathrm{T}^\text{pole}$) using several sets of parton distribution functions (PDFs). Furthermore, a simultaneous fit of the PDFs, $\alpha_S$, and $m_\mathrm{T}^\text{pole}$ is performed at NLO, demonstrating that the new data have significant impact on the gluon PDF, and at the same time allow an accurate determination of $\alpha_S$ and $m_\mathrm{T}^\text{pole}$. The values $\alpha_S(m_\mathrm{Z})$ = 0.1135 $^{+0.0021}_{-0.0017}$ and $m_\mathrm{T}^\text{pole}$ = 170.5 $\pm$ 0.8 GeV are extracted, which account for experimental and theoretical uncertainties, the latter being estimated from NLO scale variations. Possible effects from Coulomb and soft-gluon resummation near the $\mathrm{t\overline{t}}$ production threshold are neglected in these parameter extractions.

A search for charged Higgs bosons (H$^\pm$) decaying into a top and a bottom quark in the all-jet final states is presented. The analysis uses LHC proton-proton collision data recorded with the CMS detector in 2016 at $\sqrt{s} =$ 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. No significant excess is observed above the expected background. Model-independent upper limits at 95% confidence level are set on the product of the H$^\pm$ production cross section and branching fraction in two scenarios. For production in association with a top quark, limits of 21.3 to 0.007 pb are obtained for H$^\pm$ masses in the range of 0.2 to 3 TeV. Combining this with a search in leptonic final states results in improved limits of 9.25 to 0.005 pb. The complementary $s$-channel production of an H$^\pm$ is investigated in the mass range of 0.8 to 3 TeV and the corresponding upper limits are 4.5 to 0.023 pb. These results are interpreted using different minimal supersymmetric extensions of the standard model.

Measurements of production cross sections of WZ and same-sign WW boson pairs in association with two jets in proton-proton collisions at s=13TeV at the LHC are reported. The data sample corresponds to an integrated luminosity of 137fb−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 well as of the leading-lepton transverse momentum, are measured for W±W± production and are consistent with the standard model predictions. The dependence of differential cross sections on the invariant mass of the jet pair is also measured for WZ production. An observation of electroweak production of WZ boson pairs is reported with an observed (expected) significance of 6.8 (5.3) standard deviations. Constraints are obtained on the structure of quartic vector boson interactions in the framework of effective field theory.

Measurements of the top quark polarization and top quark pair (t¯t) spin correlations are presented using events containing two oppositely charged leptons (e+e−, e±μ∓, or μ+μ−) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb−1. A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the t¯t production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to −0.24<CtG/Λ2<0.07 TeV−2 and −0.33<CItG/Λ2<0.20 TeV−2, respectively, at the 95% confidence level.9 MoreReceived 8 July 2019DOI:https://doi.org/10.1103/PhysRevD.100.072002Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.© 2019 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Hadron collidersTechniquesExperimental TechniquesParticle acceleratorsHadron collidersPhysical SystemsTop quarkTechniquesHadron collidersParticles & Fields

Measurements are presented of the differential cross sections for Z bosons produced in proton-proton collisions at $\sqrt{s} =$ 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 branching fraction agrees with next-to-next-to-leading order quantum chromodynamics calculations. Differential cross sections of the transverse momentum $p_\mathrm{T}$, the optimized angular variable $\phi^*_\eta$, and the rapidity of lepton pairs are measured. The data are corrected for detector effects and compared to theoretical predictions using fixed order, resummed, and parton shower calculations. The uncertainties of the measured normalized cross sections are smaller than 0.5% for $\phi^*_\eta$ $<$ 0.5 and for $p_\mathrm{T}^\mathrm{Z}$ $<$ 50 GeV.

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 3.2σ. The measurements are based on a sample of proton-proton collisions at a center-of-mass energy sqrt[s]=13 TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb^{-1}. The cross section times branching fraction of the tt[over ¯]H process is measured to be σ_{tt[over ¯]H}B_{γγ}=1.56_{-0.32}^{+0.34} fb, which is compatible with the standard model prediction of 1.13_{-0.11}^{+0.08} fb. The fractional contribution of the CP-odd component is measured to be f_{CP}^{Htt}=0.00±0.33.

A search for anomalous electroweak production of WW, WZ, and ZZ boson pairs in association with two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV at the LHC is reported. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected with the CMS detector. Events are selected by requiring two jets with large rapidity separation and invariant mass, one or two leptons (electrons or muons), and a W or Z boson decaying hadronically. No excess of events with respect to the standard model background predictions is observed and constraints on the structure of quartic vector boson interactions in the framework of dimension-8 effective field theory operators are reported. Stringent limits on parameters of the effective field theory operators are obtained. The observed 95% confidence level limits for the S0, M0, and T0 operators are $-$2.7 $<$ f$_{\mathrm{S0}}/ \Lambda^{4}$ $<$ 2.7, $-$1.0 $<$ f$_{\mathrm{M0}}/ \Lambda^{4}$ $<$ 1.0, and $-$0.17 $<$ f$_{\mathrm{T0}}/ \Lambda^{4}$ $<$ 0.16, in units of TeV$^{-4}$. Constraints are also reported on the product of the cross section and branching fraction for vector boson fusion production of charged Higgs bosons as a function of mass from 600 to 2000 GeV. The results are interpreted in the context of the Georgi-Machacek model.

A search is presented for additional scalar (H) or pseudoscalar (A) Higgs bosons decaying to a top quark pair in proton-proton collisions at a center-of-mass energy of 13 TeV. The data set analyzed corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected by the CMS experiment at the LHC. Final states with one or two charged leptons are considered. The invariant mass of the reconstructed top quark pair system and variables that are sensitive to the spin of the particles decaying into the top quark pair are used to search for signatures of the H or A bosons. The interference with the standard model top quark pair background is taken into account. A moderate signal-like deviation compatible with an A boson with a mass of 400 GeV is observed with a global significance of 1.9 standard deviations. New stringent constraints are reported on the strength of the coupling of the hypothetical bosons to the top quark, with the mass of the bosons ranging from 400 to 750 GeV and their total relative width from 0.5 to 25%. The results of the search are also interpreted in a minimal supersymmetric standard model scenario. Values of $m_\mathrm{A}$ from 400 to 700 GeV are probed, and a region with values of $\tan\beta$ below 1.0 to 1.5, depending on $m_\mathrm{A}$, is excluded at 95% confidence level.

A search for direct top squark pair production is presented. The search is based on proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the LHC during 2016, 2017, and 2018, corresponding to an integrated luminosity of 137 fb−1. The search is carried out using events with a single isolated electron or muon, multiple jets, and large transverse momentum imbalance. The observed data are consistent with the expectations from standard model processes. Exclusions are set in the context of simplified top squark pair production models. Depending on the model, exclusion limits at 95% confidence level for top squark masses up to 1.2 TeV are set for a massless lightest supersymmetric particle, assumed to be the neutralino. For models with top squark masses of 1 TeV, neutralino masses up to 600 GeV are excluded.

The transverse momentum (pT) spectra of inclusively produced Λc+ baryons are measured via the exclusive decay channel Λc+→pK−π+ using the CMS detector at the LHC. Spectra are measured as a function of transverse momentum in proton-proton (pp) and lead-lead (PbPb) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The measurement is performed within the Λc+ rapidity interval |y|<1 in the pT range of 5–20GeV/c in pp and 10–20GeV/c in PbPb collisions. The observed yields of Λc+ for pT of 10–20GeV/c suggest a suppression in central PbPb collisions compared to pp collisions scaled by the number of nucleon-nucleon (NN) interactions. The Λc+/D0 production ratio in pp collisions is compared to theoretical models. In PbPb collisions, this ratio is consistent with the result from pp collisions in their common pT range.

A search for dark matter particles is performed using events with a Z boson candidate and large missing transverse momentum. The analysis is based on proton-proton collision data at a center-of-mass energy of 13 Te , collected by the CMS experiment at the LHC in 2016-2018, corresponding to an integrated luminosity of 137 fb-1 . The search uses the decay channels Z→ee and Z→μμ . No significant excess of events is observed over the background expected from the standard model. Limits are set on dark matter particle production in the context of simplified models with vector, axial-vector, scalar, and pseudoscalar mediators, as well as on a two-Higgs-doublet model with an additional pseudoscalar mediator. In addition, limits are provided for spin-dependent and spin-independent scattering cross sections and are compared to those from direct-detection experiments. The results are also interpreted in the context of models of invisible Higgs boson decays, unparticles, and large extra dimensions.

A tagging algorithm to identify jets that are significantly displaced from the proton-proton (pp) collision region in the CMS detector at the LHC is presented. Displaced jets can arise from the decays of long-lived particles (LLPs), which are predicted by several theoretical extensions of the standard model. The tagger is a multiclass classifier based on a deep neural network, which is parameterised according to the proper decay length $\mathrm{c}\tau_0$ of the LLP. A novel scheme is defined to reliably label jets from LLP decays for supervised learning. Samples of pp collision data, recorded by the CMS detector at a centre-of-mass energy of 13 TeV, and simulated events are used to train the neural network. Domain adaptation by backward propagation is performed to improve the simulation modelling of the jet class probability distributions observed in pp collision data. The potential performance of the tagger is demonstrated with a search for long-lived gluinos, a manifestation of split supersymmetric models. The tagger provides a rejection factor of 10 000 for jets from standard model processes, while maintaining an LLP jet tagging efficiency of 30-80% for gluinos with 1 mm $\leq$ $c\tau_0$ $\leq$ 10 m. The expected coverage of the parameter space for split supersymmetry is presented.

Measurements of Higgs boson production cross sections and couplings in events where the Higgs boson decays into a pair of photons are reported. Events are selected from a sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV collected by the CMS detector at the LHC from 2016 to 2018, corresponding to an integrated luminosity of 137 fb$^{-1}$. Analysis categories enriched in Higgs boson events produced via gluon fusion, vector boson fusion, vector boson associated production, and production associated with top quarks are constructed. The total Higgs boson signal strength, relative to the standard model (SM) prediction, is measured to be 1.12 $\pm$ 0.09. Other properties of the Higgs boson are measured, including SM signal strength modifiers, production cross sections, and its couplings to other particles. These include the most precise measurements of gluon fusion and vector boson fusion Higgs boson production in several different kinematic regions, the first measurement of Higgs boson production in association with a top quark pair in five regions of the Higgs boson transverse momentum, and an upper limit on the rate of Higgs boson production in association with a single top quark. All results are found to be in agreement with the SM expectations.

A bstract A search for nonresonant production of Higgs boson pairs via gluon-gluon and vector boson fusion processes in final states with two bottom quarks and two photons is presented. The search uses data from proton-proton collisions at a center-of-mass energy of $$ \sqrt{s} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 13 TeV recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb − 1 . No significant deviation from the background-only hypothesis is observed. An upper limit at 95% confidence level is set on the product of the Higgs boson pair production cross section and branching fraction into $$ \gamma \gamma \mathrm{b}\overline{\mathrm{b}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>γγ</mml:mi> <mml:mi>b</mml:mi> <mml:mover> <mml:mi>b</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> . The observed (expected) upper limit is determined to be 0.67 (0 . 45) fb, which corresponds to 7.7 (5.2) times the standard model prediction. This search has the highest sensitivity to Higgs boson pair production to date. Assuming all other Higgs boson couplings are equal to their values in the standard model, the observed coupling modifiers of the trilinear Higgs boson self-coupling κ λ and the coupling between a pair of Higgs bosons and a pair of vector bosons c 2V are constrained within the ranges − 3 . 3 &lt; κ λ &lt; 8 . 5 and − 1 . 3 &lt; c 2V &lt; 3 . 5 at 95% confidence level. Constraints on κ λ are also set by combining this analysis with a search for single Higgs bosons decaying to two photons, produced in association with top quark-antiquark pairs, and by performing a simultaneous fit of κ λ and the top quark Yukawa coupling modifier κ t .

The CMS detector at the CERN LHC features a silicon pixel detector as its innermost subdetector. The original CMS pixel detector has been replaced with an upgraded pixel system (CMS Phase-1 pixel detector) in the extended year-end technical stop of the LHC in 2016/2017. The upgraded CMS pixel detector is designed to cope with the higher instantaneous luminosities that have been achieved by the LHC after the upgrades to the accelerator during the first long shutdown in 2013–2014. Compared to the original pixel detector, the upgraded detector has a better tracking performance and lower mass with four barrel layers and three endcap disks on each side to provide hit coverage up to an absolute value of pseudorapidity of 2.5. This paper describes the design and construction of the CMS Phase-1 pixel detector as well as its performance from commissioning to early operation in collision data-taking.

An inclusive search is presented for long-lived particles using displaced jets. The search uses a data sample collected with the CMS detector at the CERN LHC in 2017 and 2018, from proton-proton collisions at a center-of-mass energy of 13 TeV. The results of this search are combined with those of a previous search using a data sample collected with the CMS detector in 2016, yielding a total integrated luminosity of $132\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$. The analysis searches for the distinctive topology of displaced tracks and displaced vertices associated with a dijet system. For a simplified model, where pair-produced long-lived neutral particles decay into quark-antiquark pairs, pair production cross sections larger than 0.07 fb are excluded at 95% confidence level (C.L.) for long-lived particle masses larger than 500 GeV and mean proper decay lengths between 2 and 250 mm. For a model where the standard model-like Higgs boson decays to two long-lived scalar particles that each decays to a quark-antiquark pair, branching fractions larger than 1% are excluded at 95% C.L. for mean proper decay lengths between 1 mm and 340 mm. A group of supersymmetric models with pair-produced long-lived gluinos or top squarks decaying into various final-state topologies containing displaced jets is also tested. Gluino masses up to 2500 GeV and top squark masses up to 1600 GeV are excluded at 95% C.L. for mean proper decay lengths between 3 and 300 mm. The highest lower bounds on mass reach 2600 GeV for long-lived gluinos and 1800 GeV for long-lived top squarks. These are the most stringent limits to date on these models.

A search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from b quarks, and missing transverse momentum. The search uses data from proton-proton collisions at $\sqrt{s} =$ 13 TeV collected with the CMS detector, corresponding to an integrated luminosity of 137 fb$^{-1}$. Hypothetical signal events are efficiently separated from the dominant top quark pair production background with requirements on the significance of the missing transverse momentum and on transverse mass variables. No significant deviation is observed from the expected background. Exclusion limits are set in the context of simplified supersymmetric models with pair-produced lightest top squarks. For top squarks decaying exclusively to a top quark and a lightest neutralino, lower limits are placed at 95% confidence level on the masses of the top squark and the neutralino up to 925 and 450 GeV, respectively. If the decay proceeds via an intermediate chargino, the corresponding lower limits on the mass of the lightest top squark are set up to 850 GeV for neutralino masses below 420 GeV. For top squarks undergoing a cascade decay through charginos and sleptons, the mass limits reach up to 1.4 TeV and 900 GeV respectively for the top squark and the lightest neutralino.

A search for production of the supersymmetric partners of the top quark, top squarks, is presented. The search is based on proton-proton collision events containing multiple jets, no leptons, and large transverse momentum imbalance. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 137 fb$^{-1}$. The targeted signal production scenarios are direct and gluino-mediated top squark production, including scenarios in which the top squark and neutralino masses are nearly degenerate. The search utilizes novel algorithms based on deep neural networks that identify hadronically decaying top quarks and W bosons, which are expected in many of the targeted signal models. No statistically significant excess of events is observed relative to the expectation from the standard model, and limits on the top squark production cross section are obtained in the context of simplified supersymmetric models for various production and decay modes. Exclusion limits as high as 1310 GeV are established at the 95% confidence level on the mass of the top squark for direct top squark production models, and as high as 2260 GeV on the mass of the gluino for gluino-mediated top squark production models. These results represent a significant improvement over the results of previous searches for supersymmetry by CMS in the same final state.

A search is presented for lepton-flavor violating decays of the Higgs boson to μτ and eτ. The dataset corresponds to an integrated luminosity of 137 fb−1 collected at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. No significant excess has been found, and the results are interpreted in terms of upper limits on lepton-flavor violating branching fractions of the Higgs boson. The observed (expected) upper limits on the branching fractions are, respectively, B(H→μτ)<0.15(0.15)% and B(H→eτ)<0.22(0.16)% at 95% confidence level.1 MoreReceived 6 May 2021Accepted 2 July 2021DOI:https://doi.org/10.1103/PhysRevD.104.032013Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.© 2021 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Research AreasParticle decaysPhysical SystemsHiggs bosonsTechniquesHadron collidersParticles & Fields

Genome engineering of cells using CRISPR/Cas systems has opened new avenues for pharmacological screening and investigating the molecular mechanisms of disease. A critical step in many such studies is the intracellular delivery of the gene editing machinery and the subsequent manipulation of cells. However, these workflows often involve processes such as bulk electroporation for intracellular delivery and fluorescence activated cell sorting for cell isolation that can be harsh to sensitive cell types such as human-induced pluripotent stem cells (hiPSCs). This often leads to poor viability and low overall efficacy, requiring the use of large starting samples. In this work, a fully automated version of the nanofountain probe electroporation (NFP-E) system, a nanopipette-based single-cell electroporation method is presented that provides superior cell viability and efficiency compared to traditional methods. The automated system utilizes a deep convolutional network to identify cell locations and a cell-nanopipette contact algorithm to position the nanopipette over each cell for the application of electroporation pulses. The automated NFP-E is combined with microconfinement arrays for cell isolation to demonstrate a workflow that can be used for CRISPR/Cas9 gene editing and cell tracking with potential applications in screening studies and isogenic cell line generation.

Abstract Since 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 off-shell contributions to the production cross-section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval [0.0061, 2.0] at the 95% confidence level. The scenario with no off-shell contribution is excluded at a p -value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as $${{{\varGamma }}}_{{{{{{\rm{H}}}}}}}={3.2}_{-1.7}^{+2.4}\,{{{{{\rm{MeV}}}}}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>Γ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>H</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>3.2</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1.7</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>2.4</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace /> <mml:mi>MeV</mml:mi> </mml:mrow> </mml:math> , in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs.

A search for the direct production of a pair of $\ensuremath{\tau}$ sleptons, the supersymmetric partners of $\ensuremath{\tau}$ leptons, is presented. Each $\ensuremath{\tau}$ slepton is assumed to decay to a $\ensuremath{\tau}$ lepton and the lightest supersymmetric particle (LSP), which is assumed to be stable and to not interact in the detector, leading to an imbalance in the total reconstructed transverse momentum. The search is carried out in events identified as containing two $\ensuremath{\tau}$ leptons, each decaying to one or more hadrons and a neutrino, and significant transverse momentum imbalance. In addition to scenarios in which the $\ensuremath{\tau}$ sleptons decay promptly, the search also addresses scenarios in which the $\ensuremath{\tau}$ sleptons have sufficiently long lifetimes to give rise to nonprompt $\ensuremath{\tau}$ leptons. The data were collected in proton-proton collisions at a center-of-mass energy of $13\text{ }\text{ }\mathrm{TeV}$ at the CERN LHC with the CMS detector in 2016--2018, and correspond to an integrated luminosity of $138\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$. No significant excess is seen with respect to standard model expectations. Upper limits on cross sections for the pair production of $\ensuremath{\tau}$ sleptons are obtained in the framework of simplified models. In a scenario in which the $\ensuremath{\tau}$ sleptons are superpartners of left-handed $\ensuremath{\tau}$ leptons, and each undergoes a prompt decay to a $\ensuremath{\tau}$ lepton and a nearly massless LSP, $\ensuremath{\tau}$ slepton masses between 115 and 340 GeV are excluded. In a scenario in which the lifetime of the $\ensuremath{\tau}$ sleptons corresponds to $c{\ensuremath{\tau}}_{0}=0.1\text{ }\text{ }\mathrm{mm}$, where ${\ensuremath{\tau}}_{0}$ represents the mean proper lifetime of the $\ensuremath{\tau}$ slepton, masses between 150 and 220 GeV are excluded.

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cc[over ¯], produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at sqrt[s]=13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb^{-1}. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cc[over ¯] in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cc[over ¯]) is 0.94 (0.50_{-0.15}^{+0.22})pb at 95% confidence level (C.L.), corresponding to 14 (7.6_{-2.3}^{+3.4}) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ_{c}, the observed (expected) 95% C.L. interval is 1.1<|κ_{c}|<5.5 (|κ_{c}|<3.4), the most stringent constraint to date.

A bstract The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z → τ + τ − events 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 recorded by CMS at the CERN LHC with an integrated luminosity of 36.3 fb − 1 . The measured τ − lepton polarization at the Z boson mass pole is $$ {\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>P</mml:mi> <mml:mi>τ</mml:mi> </mml:msub> <mml:mfenced> <mml:mi>Z</mml:mi> </mml:mfenced> </mml:math> = −0.144 ± 0.006 (stat) ± 0.014 (syst) = −0.144 ± 0.015, in good agreement with the measurement of the τ lepton asymmetry parameter of A τ = 0.1439 ± 0.0043 = $$ -{\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>−</mml:mo> <mml:msub> <mml:mi>P</mml:mi> <mml:mi>τ</mml:mi> </mml:msub> <mml:mfenced> <mml:mi>Z</mml:mi> </mml:mfenced> </mml:math> at LEP. The τ lepton polarization depends on the ratio of the vector to axial-vector couplings of the τ leptons in the neutral current expression, and thus on the effective weak mixing angle sin 2 $$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>θ</mml:mi> <mml:mi>W</mml:mi> <mml:mi>eff</mml:mi> </mml:msubsup> </mml:math> , independently of the Z boson production mechanism. The obtained value sin 2 $$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>θ</mml:mi> <mml:mi>W</mml:mi> <mml:mi>eff</mml:mi> </mml:msubsup> </mml:math> = 0.2319 ± 0 . 0008(stat) ± 0 . 0018(syst) = 0 . 2319 ± 0 . 0019 is in good agreement with measurements at e + e − colliders.

A bstract The production of prompt $$ {\Lambda}_{\textrm{c}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> baryons is measured via the exclusive decay channel $$ {\Lambda}_{\textrm{c}}^{+}\to p{\textrm{K}}^{-}{\pi}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> <mml:mo>→</mml:mo> <mml:mi>p</mml:mi> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>−</mml:mo> </mml:msup> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> at a center-of-mass energy per nucleon pair of 5.02 TeV, using proton-proton (pp) and lead-lead (PbPb) collision data collected by the CMS experiment at the CERN LHC. The pp and PbPb data were obtained in 2017 and 2018 with integrated luminosities of 252 and 0.607 nb − 1 , respectively. The measurements are performed within the $$ {\Lambda}_{\textrm{c}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> rapidity interval | y | &lt; 1 with transverse momentum ( p T ) ranges of 3–30 and 6–40 GeV/ c for pp and PbPb collisions, respectively. Compared to the yields in pp collisions scaled by the expected number of nucleon-nucleon interactions, the observed yields of $$ {\Lambda}_{\textrm{c}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> with p T &gt; 10 GeV/ c are strongly suppressed in PbPb collisions. The level of suppression depends significantly on the collision centrality. The $$ {\Lambda}_{\textrm{c}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> / D 0 production ratio is similar in PbPb and pp collisions at p T &gt; 10 GeV/ c , suggesting that the coalescence process does not play a dominant role in prompt $$ {\Lambda}_{\textrm{c}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Λ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> baryon production at higher p T .

The first search for scalar leptoquarks produced in τ-lepton–quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb−1. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength.Received 11 August 2023Accepted 19 December 2023DOI:https://doi.org/10.1103/PhysRevLett.132.061801Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.© 2024 CERN, for the CMS CollaborationPhysics Subject Headings (PhySH)Physical SystemsLeptoquarksTau leptonsTechniquesHadron collidersParticles & Fields

17O solid state NMR of organic materials is developing rapidly. This article provides a snapshot of the current state of development of this field. The NMR techniques and enrichment protocols that are driving this progress are outlined. The 17O parameters derived from solid-state NMR experiments are summarized and the structural sensitivity of the approach to effects such as hydrogen bonding highlighted. The prospects and challenges for 17O solid-state NMR of biomolecules are discussed.

Matrix element reweighting is a powerful experimental technique widely employed to maximize the amount of information that can be extracted from a collider data set. We present a procedure that allows to automatically evaluate the weights for any process of interest in the standard model and beyond. Given the initial, intermediate and final state particles, and the transfer functions for the final physics objects, such as leptons, jets, missing transverse energy, our algorithm creates a phase-space mapping designed to efficiently perform the integration of the squared matrix element and the transfer functions. The implementation builds up on MadGraph, it is completely automatized and publicly available. A few sample applications are presented that show the capabilities of the code and illustrate the possibilities for new studies that such an approach opens up.

This paper presents a new C++ framework, DELPHES, performing a fast multipurpose detector response simulation. The simulation includes a tracking system, embedded into a magnetic field, calorimeters and a muon system, and possible very forward detectors arranged along the beamline. The framework is interfaced to standard file formats (e.g. Les Houches Event File or HepMC) and outputs observables such as isolated leptons, missing transverse energy and collection of jets which can be used for dedicated analyses. The simulation of the detector response takes into account the effect of magnetic field, the granularity of the calorimeters and subdetector resolutions. A simplified preselection can also be applied on processed events for trigger emulation. Detection of very forward scattered particles relies on the transport in beamlines with the HECTOR software. Finally, the FROG 2D/3D event display is used for visualisation of the collision final states.