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1.
Eur Phys J C Part Fields ; 83(8): 742, 2023.
Article in English | MEDLINE | ID: mdl-37623740

ABSTRACT

Multijet events at large transverse momentum (pT) are measured at s=13TeV using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 36.3fb-1. The multiplicity of jets with pT>50GeV that are produced in association with a high-pT dijet system is measured in various ranges of the pT of the jet with the highest transverse momentum and as a function of the azimuthal angle difference Δϕ1,2 between the two highest pT jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest pT jets. The measurements are compared with leading and next-to-leading order matrix element calculations supplemented with simulations of parton shower, hadronization, and multiparton interactions. In addition, the measurements are compared with next-to-leading order matrix element calculations combined with transverse-momentum dependent parton densities and transverse-momentum dependent parton shower.

2.
Eur Phys J C Part Fields ; 83(8): 722, 2023.
Article in English | MEDLINE | ID: mdl-37578844

ABSTRACT

The production of Z bosons associated with jets is measured in pp collisions at s=13TeV with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3fb-1. The multiplicity of jets with transverse momentum pT>30GeV is measured for different regions of the Z boson's pT(Z), from lower than 10GeV to higher than 100GeV. The azimuthal correlation Δϕ between the Z boson and the leading jet, as well as the correlations between the two leading jets are measured in three regions of pT(Z). The measurements are compared with several predictions at leading and next-to-leading orders, interfaced with parton showers. Predictions based on transverse-momentum dependent parton distributions and corresponding parton showers give a good description of the measurement in the regions where multiple parton interactions and higher jet multiplicities are not important. The effects of multiple parton interactions are shown to be important to correctly describe the measured spectra in the low pT(Z) regions.

3.
Phys Rev Lett ; 131(5): 051901, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37595238

ABSTRACT

The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at sqrt[s_{NN}]=5.02 TeV, corresponding to an integrated luminosity of 0.38 nb^{-1}, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet transverse momentum vectors is found to be positive, and rising, as the dijet transverse momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.

4.
Eur Phys J C Part Fields ; 83(7): 628, 2023.
Article in English | MEDLINE | ID: mdl-37471210

ABSTRACT

The double differential cross sections of the Drell-Yan lepton pair (ℓ+ℓ-, dielectron or dimuon) production are measured as functions of the invariant mass mℓℓ, transverse momentum pT(ℓℓ), and φη∗. The φη∗ observable, derived from angular measurements of the leptons and highly correlated with pT(ℓℓ), is used to probe the low-pT(ℓℓ) region in a complementary way. Dilepton masses up to 1TeV are investigated. Additionally, a measurement is performed requiring at least one jet in the final state. To benefit from partial cancellation of the systematic uncertainty, the ratios of the differential cross sections for various mℓℓ ranges to those in the Z mass peak interval are presented. The collected data correspond to an integrated luminosity of 36.3fb-1 of proton-proton collisions recorded with the CMS detector at the LHC at a centre-of-mass energy of 13TeV. Measurements are compared with predictions based on perturbative quantum chromodynamics, including soft-gluon resummation.

5.
Eur Phys J C Part Fields ; 83(7): 571, 2023.
Article in English | MEDLINE | ID: mdl-37432681

ABSTRACT

A search is reported for pairs of light Higgs bosons (H1) produced in supersymmetric cascade decays in final states with small missing transverse momentum. A data set of LHC pp collisions collected with the CMS detector at s=13TeV and corresponding to an integrated luminosity of 138fb-1 is used. The search targets events where both H1 bosons decay into pairs that are reconstructed as large-radius jets using substructure techniques. No evidence is found for an excess of events beyond the background expectations of the standard model (SM). Results from the search are interpreted in the next-to-minimal supersymmetric extension of the SM, where a "singlino" of small mass leads to squark and gluino cascade decays that can predominantly end in a highly Lorentz-boosted singlet-like H1 and a singlino-like neutralino of small transverse momentum. Upper limits are set on the product of the squark or gluino pair production cross section and the square of the branching fraction of the H1 in a benchmark model containing almost mass-degenerate gluinos and light-flavour squarks. Under the assumption of an SM-like branching fraction, H1 bosons with masses in the range 40-120GeV arising from the decays of squarks or gluinos with a mass of 1200-2500GeV are excluded at 95% confidence level.

6.
Eur Phys J C Part Fields ; 83(7): 587, 2023.
Article in English | MEDLINE | ID: mdl-37440247

ABSTRACT

New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia  8 event generator, are obtained based on the default CMS pythia  8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies s=7 and 13TeV, and by the CDF experiment at 1.96TeV are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously. The new colour reconnection tunes are compared with various measurements at 1.96, 7, 8, and 13TeV including measurements of the underlying-event, strange-particle multiplicities, jet substructure observables, jet shapes, and colour flow in top quark pair (tt¯) events. The new tunes are also used to estimate the uncertainty related to colour reconnection modelling in the top quark mass measurement using the decay products of tt¯ events in the semileptonic channel at 13TeV.

7.
Gynecol Obstet Fertil Senol ; 51(3): 186-189, 2023 03.
Article in French | MEDLINE | ID: mdl-36642328

ABSTRACT

Central disorders of hypersomnolence include narcolepsy type 1, narcolepsy type 2, idiopathic hypersomnia and hypersomnia associated with medical or mental disorders. Treatment is both non-pharmacological and pharmacological, including wake enhancing drugs and stimulants. One of the first-line treatment (modafinil, MODIODAL®) was the subject of a health authority alert in 2019 concerning a risk of major congenital malformations when taken during organogenesis. Since this date, three epidemiological studies have presented contradictory results. Given their methodological weaknesses, it is not possible at this stage to confirm or deny such a risk for the embryo and its nature if there is one. In clinical practice, because of these uncertainties, it is preferable if possible to suspend the treatment of a pregnant woman during the first 10 weeks from last menstrual period (organogenesis). There is an unmet clinical need for research to clarify the potential teratogenic impact of modafinil.


Subject(s)
Central Nervous System Stimulants , Disorders of Excessive Somnolence , Idiopathic Hypersomnia , Narcolepsy , Female , Humans , Modafinil/adverse effects , Narcolepsy/drug therapy , Narcolepsy/etiology , Disorders of Excessive Somnolence/chemically induced , Disorders of Excessive Somnolence/complications , Disorders of Excessive Somnolence/drug therapy , Central Nervous System Stimulants/adverse effects , Idiopathic Hypersomnia/complications , Idiopathic Hypersomnia/drug therapy
8.
Phys Rev Lett ; 129(8): 081802, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-36053704

ABSTRACT

A search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138 fb^{-1}. No deviation from the background-only hypothesis is observed. A 95% confidence level upper limit on the Higgs boson pair production cross section is observed at 3.9 times the standard model prediction for an expected value of 7.8. Constraints are also set on the modifiers of the Higgs field self-coupling, κ_{λ}, and of the coupling of two Higgs bosons to two vector bosons, κ_{2 V}. The observed (expected) allowed intervals at the 95% confidence level are -2.3<κ_{λ}<9.4 (-5.0<κ_{λ}<12.0) and -0.1<κ_{2 V}<2.2 (-0.4<κ_{2 V}<2.5). These are the most stringent observed constraints to date on the HH production cross section and on the κ_{2 V } coupling.

9.
Phys Rev Lett ; 128(25): 252301, 2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35802434

ABSTRACT

The B_{c}^{+} meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the B_{c}^{+} meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02 TeV, via the B_{c}^{+}→(J/ψ→µ^{+}µ^{-})µ^{+}ν_{µ} decay. The B_{c}^{+} nuclear modification factor, derived from the Pb-Pb-to-pp ratio of production cross sections, is measured in two bins of the trimuon transverse momentum and of the Pb-Pb collision centrality. The B_{c}^{+} meson is shown to be less suppressed than quarkonia and most of the open heavy-flavor mesons, suggesting that effects of the hot and dense nuclear matter created in heavy ion collisions contribute to its production. This measurement sets forth a promising new probe of the interplay of suppression and enhancement mechanisms in the production of heavy-flavor mesons in the quark-gluon plasma.

10.
Phys Rev Lett ; 129(3): 032001, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35905365

ABSTRACT

Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb^{-1}. No significant excess above the background prediction is observed. Upper limits on the branching fractions (B) of the top quark decaying to a Higgs boson and an up (u) or charm (c) quark are derived through a binned fit to the diphoton invariant mass spectrum. The observed (expected) 95% confidence level upper limits are found to be 0.019% (0.031%) for B(t→Hu) and 0.073% (0.051%) for B(t→Hc). These are the strictest upper limits yet determined.

11.
Phys Rev Lett ; 129(2): 021802, 2022 Jul 08.
Article in English | MEDLINE | ID: mdl-35867460

ABSTRACT

A search for resonances decaying into a W boson and a radion, where the radion decays into two W bosons, is presented. The data analyzed correspond to an integrated luminosity of 138 fb^{-1} recorded in proton-proton collisions with the CMS detector at sqrt[s]=13 TeV. One isolated charged lepton is required, together with missing transverse momentum and one or two massive large-radius jets, containing the decay products of either two or one W bosons, respectively. No excess over the background estimation is observed. The results are combined with those from a complementary channel with an all-hadronic final state, described in an accompanying paper. Limits are set on parameters of an extended warped extra-dimensional model. These searches are the first of their kind at the LHC.

12.
Phys Rev Lett ; 129(2): 022001, 2022 Jul 08.
Article in English | MEDLINE | ID: mdl-35867464

ABSTRACT

Multiparticle azimuthal correlations of prompt D^{0} mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02 TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (v_{2}) of D^{0} mesons as a function of event centrality and the D^{0} transverse momentum. The ratios of the four-particle v_{2} values to previously measured two-particle cumulant results provide direct experimental access to event-by-event fluctuations of charm quark azimuthal anisotropies. These ratios are also found to be comparable to those of inclusive charged particles in the event. However, hints of deviations are seen in the most central and peripheral collisions. To investigate the origin of flow fluctuations in the charm sector, these measurements are compared to a model implementing fluctuations of charm quark energy loss via collisional or radiative processes in the quark-gluon plasma. These models cannot quantitatively describe the data over the full transverse momentum and centrality ranges, although the calculations with collisional energy loss provide a better description of the data.

13.
Eur Phys J C Part Fields ; 82(5): 499, 2022.
Article in English | MEDLINE | ID: mdl-35666690

ABSTRACT

Using a data sample of s = 13 TeV proton-proton collisions collected by the CMS experiment at the LHC in 2017 and 2018 with an integrated luminosity of 103 fb - 1 , the B s 0 → ψ ( 2S ) K S 0 and B 0 → ψ ( 2S ) K S 0 π + π - decays are observed with significances exceeding 5 standard deviations. The resulting branching fraction ratios, measured for the first time, correspond to B ( B s 0 → ψ ( 2S ) K S 0 ) / B ( B 0 → ψ ( 2S ) K S 0 ) = ( 3.33 ± 0.69 ( stat ) ± 0.11 ( syst ) ± 0.34 ( f s / f d ) ) × 10 - 2 and B ( B 0 → ψ ( 2S ) K S 0 π + π - ) / B ( B 0 → ψ ( 2S ) K S 0 ) = 0.480 ± 0.013 ( stat ) ± 0.032 ( syst ) , where the last uncertainty in the first ratio is related to the uncertainty in the ratio of production cross sections of B s 0 and B 0 mesons, f s / f d .

14.
Ann Chir Plast Esthet ; 67(4): 183-188, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35764445

ABSTRACT

INTRODUCTION: Breast augmentation is one of the most frequently performed cosmetic surgeries in the world. However, there is no standardized surgical procedure for performing breast augmentation. Many modalities exist for this surgery which may explain why practices vary greatly from one surgeon to another. The aim of this study was to evaluate current practices of breast augmentation by implant in France and changes in practices among French plastic surgeons. MATERIAL AND METHODS: This observational study was conducted between February 2020 and January 2021. An online questionnaire with 62 questions was sent to 729 French plastic surgeons. The questions concerned: the population of surgeons interviewed, pre-operative aspects, surgical technique and post-operative management. RESULTS: 411 plastic surgeons responded, 5.1% of surgeons impose a nicotine screening test on patients. 99.76% and 95.59% reported that they used silicone gel implants and round prostheses. All used smooth or micro-textured shells. The inframammary approach was the most used by 66.2% of plastic surgeons. The implants placed were between 250 and 300 cc on average and were mainly placed in "Dual plane" by 42% of surgeons. In order to reduce bacterial contamination, 26% of surgeons soaked the implants in a povidone-iodine solution and 23% used an insertion sleeve. The most frequent early complication was hematoma, while capsular contracture was a late complication. CONCLUSION: This study provides new data on current surgical practices of breast augmentation in France, allowing more informed choices and opening up perspectives for more standardized practices in the future.


Subject(s)
Breast Implantation , Breast Implants , Mammaplasty , Surgeons , Humans , Silicone Gels
15.
Phys Rev Lett ; 128(8): 081805, 2022 Feb 25.
Article in English | MEDLINE | ID: mdl-35275660

ABSTRACT

Measurements of the inclusive and differential fiducial cross sections of the Higgs boson are presented, using the τ lepton decay channel. The differential cross sections are measured as functions of the Higgs boson transverse momentum, jet multiplicity, and transverse momentum of the leading jet in the event, if any. The analysis is performed using proton-proton collision data collected with the CMS detector at the LHC at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 138 fb^{-1}. These are the first differential measurements of the Higgs boson cross section in the final state of two τ leptons. In final states with a large jet multiplicity or with a Lorentz-boosted Higgs boson, these measurements constitute a significant improvement over measurements performed in other final states.

16.
Eur Phys J C Part Fields ; 82(2): 153, 2022.
Article in English | MEDLINE | ID: mdl-35226718

ABSTRACT

A search for new long-lived particles decaying to leptons using proton-proton collision data produced by the CERN LHC at s = 13 Te is presented. Events are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10 cm and are not required to form a common vertex. Data used for the analysis were collected with the CMS detector in 2016, 2017, and 2018, and correspond to an integrated luminosity of 118 (113) fb - 1 in the e e channel ( e µ and µ µ channels). The search is designed to be sensitive to a wide range of models with displaced e µ , e e , and µ µ final states. The results constrain several well-motivated models involving new long-lived particles that decay to displaced leptons. For some areas of the available phase space, these are the most stringent constraints to date.

17.
Gynecol Obstet Fertil Senol ; 50(5): 422-425, 2022 05.
Article in French | MEDLINE | ID: mdl-35219913

ABSTRACT

Physiological changes that occur during pregnancy in the maternal body can lead to alterations in the response to drugs in the mother. Pregnancy modifies the volume of distribution of drugs, their binding to plasma proteins, the activity of their metabolizing enzymes, and their elimination. However, to date, due to the dynamic and complex processes involved, adjustments to the dosage regimen during pregnancy remain impossible to standardize. Knowledge of these modifications will help to better understand the possible loss of drug efficacy during pregnancy, as well as anticipating the clinical and plasma monitoring of drugs with a low therapeutic margin.


Subject(s)
Pharmaceutical Preparations , Pharmacokinetics , Female , Humans , Pregnancy/metabolism
18.
Eur Phys J C Part Fields ; 81(9): 800, 2021.
Article in English | MEDLINE | ID: mdl-34781320

ABSTRACT

The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton-proton collisions at s = 13 TeV 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.

19.
Eur Phys J C Part Fields ; 81(6): 488, 2021.
Article in English | MEDLINE | ID: mdl-34727143

ABSTRACT

Production cross sections of the Higgs boson are measured in the H → Z Z → 4 ℓ ( ℓ = e , µ ) 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 µ , defined as the ratio of the Higgs boson production rate in the 4 ℓ channel to the standard model (SM) expectation, is measured to be µ = 0.94 ± 0.07 (stat) - 0.08 + 0.09 (syst) at a fixed value of m 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 → 4 ℓ process is measured to be 2 . 84 - 0.22 + 0.23 (stat) - 0.21 + 0.26 (syst) fb , which is compatible with the SM prediction of 2.84 ± 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.

20.
Phys Rev Lett ; 127(19): 191801, 2021 Nov 05.
Article in English | MEDLINE | ID: mdl-34797136

ABSTRACT

The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst) pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst) pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.

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