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Differential cross section measurements for the production of top quark pairs and of additional jets using dilepton events from pp collisions at = 13 TeV
No full textInternational audienceDifferential cross sections for top quark pair () production are measured in proton-proton collisions at a center-of-mass energy of 13 TeV using a sample of events containing two oppositely charged leptons. The data were recorded with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 138 fb. The differential cross sections are measured as functions of kinematic observables of the system, the top quark and antiquark and their decay products, as well as of the number of additional jets in the event. The results are presented as functions of up to three variables and are corrected to the parton and particle levels. When compared to standard model predictions based on quantum chromodynamics at different levels of accuracy, it is found that the calculations do not always describe the observed data. The deviations are found to be largest for the multi-differential cross sections
Test of lepton flavour universality with decays
No full textInternational audienceLepton flavour universality in rare transitions is tested for the first time using meson decays. The measurements are performed using collision data collected by the LHCb experiment between 2011 and 2018, corresponding to a total integrated luminosity of 9. Branching fraction ratios between the and decays are measured in three regions of dilepton mass squared, , with , , and . The results agree with the Standard Model expectation of lepton flavour universality
Supervised Contamination Detection, with Flow Cytometry Application
No full textInternational audienceThe contamination detection problem aims to determine whether a set of observations has been contaminated, i.e. whether it contains points drawn from a distribution different from the reference distribution. Here, we consider a supervised problem, where labeled samples drawn from both the reference distribution and the contamination distribution are available at training time. This problem is motivated by the detection of rare cells in flow cytometry. Compared to novelty detection problems or two-sample testing, where only samples from the reference distribution are available, the challenge lies in efficiently leveraging the observations from the contamination detection to design more powerful tests. In this article, we introduce a test for the supervised contamination detection problem. We provide non-asymptotic guarantees on its Type I error, and characterize its detection rate. The test relies on estimating reference and contamination densities using histograms, and its power depends strongly on the choice of the corresponding partition. We present an algorithm for judiciously choosing the partition that results in a powerful test. Simulations illustrate the good empirical performances of our partition selection algorithm and the efficiency of our test. Finally, we showcase our method and apply it to a real flow cytometry dataset
Tree-based conditional copula estimation
No full textInternational audienceThis paper proposes a regression tree procedure to estimate conditional copulas. The associated algorithm determines classes of observations based on covariate values and fits a simple parametric copula model on each class. The association parameter changes from one class to another, allowing for non-linearity in the dependence structure modeling. It also allows the definition of classes of observations on which the so-called "simplifying assumption" see Derumigny and Fermanian, 2017] holds reasonably well. When considering observations belonging to a given class separately, the association parameter no longer depends on the covariates according to our model. In this paper, we derive asymptotic consistency results for the regression tree procedure and show that the proposed pruning methodology, that is the model selection techniques selecting the appropriate number of classes, is optimal in some sense. Simulations provide finite sample results and an analysis of data of cases of human influenza presents the practical behavior of the procedure
Scaling limit of random plane quadrangulations with a simple boundary, via restriction
No full textInternational audienceThe main purpose of this work is to provide a framework for proving that, given a family of random maps known to converge in the Gromov--Hausdorff sense, then some (suitable) conditional families of random maps converge to the same limit. As a proof of concept, we show that quadrangulations with a simple boundary converge to the Brownian disk. More precisely, we fix a sequence of even positive integers with for some . Then, for the Gromov--Hausdorff topology, a quadrangulation with a simple boundary uniformly sampled among those with inner faces and boundary length weakly converges, in the usual scaling , toward the Brownian disk of perimeter
A randomised study comparing performance and safety of Eyestil Plus® vs Vismed Multi® in moderate-to-severe dry eye syndrome patients
No full textInternational audiencePURPOSE: This clinical investigation compared the performance and safety of Eyestil Plus® (SIFI) and Vismed Multi® (TRB Chemedica) for reducing keratitis lesions in moderate-to-severe dry eye disease (DED) patients. MATERIALS AND METHODS: This was a randomised, double-blind, multicentre investigation. 96 adults (>18 years of age) with moderate-to-severe DED received Eyestil Plus® (N = 48) or Vismed Multi® (n = 48) 6 times daily for 3 months. The primary objective clinical performance after 1 month as global corneal and conjunctival staining scores. The secondary objectives were clinical performance after 3 months, tear film stability (tear break up time (TBUT), tear production (Schirmer test), patient-reported outcomes (PROs), investigator satisfaction, and safety. RESULTS: 96 participants were randomised to receive the clinical investigations' treatments, 82.3% of them were female and their mean age was 65.8 years. The non-inferiority of Eyestil Plus® for moderate-to-severe DED was demonstrated at 1 month. No statistical difference was found for any of the study's objectives: change at 1 and 3 months of the global corneal and conjunctival staining score (p-value = 0.506 and 0.661, respectively), change at 1 and 3 months (p-value = 0.538 and 0.302) for TBUT test; change at 3 months for Schirmer test (p-value = 0.540). There were no changes for PROs either. Investigator satisfaction was high for both products. 16.6% of the participants experienced adverse events. CONCLUSION: This clinical investigation showed the non-inferiority of Eyestil Plus® compared to Vismed Multi® regarding performance and safety in a moderate-to-severe DED population
(Online) Convex Optimization for Demand-Side Management: Application to Thermostatically Controlled Loads
No full textInternational audienceTo counter the challenge of integrating fluctuating renewables into the grid, devices like thermostatically controlled loads (water-heaters, air conditioners, etc) offer flexible demand. However, efficiently controlling a large population of these devices to track desired consumption signals remains a complex challenge. Existing methods lack convergence guarantees and computational efficiency, or resort to regularization techniques instead of tackling the target tracking problem directly. This work addresses these drawbacks. We propose to model the problem as a finite horizon episodic Markov decision process, enabling us to adapt convex optimization algorithms with convergence guarantees and computational efficiency. This framework also extends to online learning scenarios, where daily control decisions are made without prior knowledge of consumer behavior and with daily-changing target profiles due to fluctuations of energy production and inflexible consumption. We introduce a new algorithm, called Online Target Tracker (OTT), the first online learning load control method, for which we prove sub-linear regret. We demonstrate our claims with realistic experiments. This combination of optimization and learning lays the groundwork for more dynamic and efficient load control methods
Search for long-lived heavy neutral leptons in proton-proton collision events with a lepton-jet pair associated with a secondary vertex at = 13 TeV
No full textInternational audienceA search for long-lived heavy neutral leptons (HNLs) using proton-proton collision data corresponding to an integrated luminosity of 138 fb collected at = 13 TeV with the CMS detector at the CERN LHC is presented. Events are selected with a charged lepton originating from the primary vertex associated with the proton-proton interaction, as well as a second charged lepton and a hadronic jet associated with a secondary vertex that corresponds to the semileptonic decay of a long-lived HNL. No excess of events above the standard model expectation is observed. Exclusion limits at 95% confidence level are evaluated for HNLs that mix with electron and/or muon neutrinos. Limits are presented in the mass range of 1-16.5 GeV, with excluded square mixing parameter values reaching as low as 2 10. For masses above 11 GeV, the presented limits exceed all previous results in the semileptonic decay channel, and for some of the considered scenarios are the strongest to date
Constraints on the Higgs boson self-coupling from the combination of single and double Higgs boson production in proton-proton collisions at = 13 TeV
No full textInternational audienceThe Higgs boson (H) trilinear self-coupling, , is constrained via its measured properties and limits on the HH pair production using the proton-proton collision data collected by the CMS experiment at = 13 TeV. The combination of event categories enriched in single-H and HH events is used to measure , defined as the value of normalized to its standard model prediction, while simultaneously constraining the Higgs boson couplings to fermions and vector bosons. Values of outside the interval 1.2 7.5 are excluded at 2 confidence level, which is compatible with the expected range of 2.0 7.7 under the assumption that all other Higgs boson couplings are equal to their standard model predicted values. Relaxing the assumption on the Higgs couplings to fermions and vector bosons the observed (expected) interval is constrained to be within 1.4 7.8 (2.3 7.8) at 2 confidence level
One-Dimensional Carrollian Fluids III: Global Existence and Weak Continuity in
No full textInternational audienceThe Carrollian fluid equations arise as the limit of the relativistic fluid equations and have recently experienced a surge of activity in the flat-space holography community. However, the rigorous mathematical well-posedness theory for these equations does not appear to have been previously studied. This paper is the third in a series in which we initiate the systematic analysis of the Carrollian fluid equations. In the present work we prove the global-in-time existence of bounded entropy solutions to the isentropic Carrollian fluid equations in one spatial dimension for a particular constitutive law (). Our method is to use a vanishing viscosity approximation for which we establish a compensated compactness framework. Using this framework we also prove the compactness of entropy solutions in , and establish a kinetic formulation of the problem. This global existence result in extends the theory presented in our companion paper ``One-Dimensional Carrollian Fluids II: Blow-up Criteria''