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Homoepitaxial growth of device-grade GaAs using low-pressure remote plasma CVD
No full textInternational audienc
Line-shape parameters and their temperature dependence for self-broadened CO2 lines in the 296 K- 1250 K range by requantized classical molecular dynamics simulations
No full textInternational audienceLine-shape parameters for self-broadened CO2 transitions are predicted for temperaturesranging from 296 K to 1250 K, using requantized molecular dynamics simulations (rCMDS).The line broadening coefficient, the speed dependence component and the first-order line-mixing coefficient for lines with rotational quantum number from 2 to 100, have beendetermined from fits of the rCMDS spectra with the Voigt and speed dependent Voigtprofiles. These parameters and their temperature dependences were compared with recenthigh-quality measurements at both room and high temperatures, showing good agreements forall considered parameters. In particular, this study highlights that the temperature dependenceof the speed dependent Voigt line broadening coefficient in the HITRAN database needs to becorrected. Additionally, we demonstrate that the temperature dependence for the speeddependence of the line broadening differs from that of the line broadening, contrary to theassumption widely used in the literature. These findings confirm the quality of theoreticalpredictions using rCMDS. The data provided can be used to complete and improvespectroscopic databases for various applications
La performance financière des fonds d'investissement solidaires en France
No full textThis article examines the financial performance of French solidarity-based investment funds, also known as "90-10 funds", which combine 90% responsible listed assets and 10% solidarity assets from Social and Solidarity Economy (SSE) enterprises. These funds have grown significantly since the early 2000s, in response to the challenges of sustainable development and SSE financing. However, their dual objectives-stemming from their hybrid structure, which seeks both financial returns and social impact-raise important questions about their (under)performance compared to conventional funds. Based on an original sample of 49 French solidarity-based investment funds, this study investigates the factors influencing their financial performance, with particular attention to the role of their solidarity component and their level of sustainability commitment over the period 2020-2023. Key insights emerge from this study: i) the in-depth statistical analysis reveal that these funds perform close to their benchmarks, while displaying lower volatility and risk exposure, as evidenced by beta coefficients and information ratios; ii) the econometric analysis, highlights a statistically significant and substantial negative impact of the solidarity component on financial performance. However, this factor alone does not fully account for the observed underperformance, which also reflects the influence of sustainability constraints and the presence of a non-linear relationship between ESG intensity and returns.</div
Zeeman splitting observations in laser-produced magnetized blast waves
No full textInternational audienceWe report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced, magnetized plasma (1–3 × 1018 cm−3, 1–15 eV) in the context of a laboratory astrophysics experiment under a controlled magnetic field up to 20 T. Nitrogen lines (NII) in the visible range (563–574 nm) were used to diagnose the magnetic field and plasma conditions. This was performed by coupling our data with the Stark–Zeeman line-shape code PPPB. The excellent agreement between experiment and simulations paves the way for a non-intrusive experimental platform to get time-resolved measurements of the local magnetic field in laboratory plasmas
Measurement of neutron production in atmospheric neutrino interactions at Super-Kamiokande
No full textInternational audienceWe present measurements of total neutron production from atmospheric neutrino interactions in water, analyzed as a function of the electron-equivalent visible energy over a range of 30 MeV to 10 GeV. These results are based on 4,270 days of data collected by Super-Kamiokande, including 564 days with 0.011 wt% gadolinium added to enhance neutron detection. The measurements are compared to predictions from neutrino event generators combined with various hadron-nucleus interaction models, which consist of an intranuclear cascade model and a nuclear de-excitation model. We observe significant variations in the predictions depending on the choice of hadron-nucleus interaction model. We discuss key factors that contribute to describing our data, such as in-medium effects in the intranuclear cascade and the accuracy of statistical evaporation modeling
Time-lagged recurrence: A data-driven method to estimate the predictability of dynamical systems
No full textInternational audienceNonlinear dynamical systems are ubiquitous in nature and they are hard to forecast. Not only they may be sensitive to small perturbations in their initial conditions, but they are often composed of processes acting at multiple scales. Classical approaches based on the Lyapunov spectrum rely on the knowledge of the dynamic forward operator, or of a data-derived approximation of it. This operator is typically unknown, or the data are too noisy to derive its faithful representation. Here, we propose a data-driven approach to analyze the local predictability of dynamical systems. This method, based on the concept of recurrence, is closely linked to the well-established framework of local dynamical indices. When applied to both idealized systems and real-world datasets arising from large-scale atmospheric fields, our approach proves its effectiveness in estimating local predictability. Additionally, we discuss its relationship with other local dynamical indices, and how it reveals the scale-dependent nature of predictability. Furthermore, we explore its link to information theory, its extension that includes a weighting strategy, and its real-time application. We believe these aspects collectively demonstrate its potential as a powerful diagnostic tool for complex systems
Search for excited tau leptons in the final state in proton-proton collisions at = 13 TeV
No full textInternational audienceResults are presented for a test of the compositeness of the heaviest charged lepton, , using data collected by the CMS experiment in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC. The data were collected in 2016-2018 and correspond to an integrated luminosity of 138 fb. This analysis searches for tau lepton pair production in which one of the tau leptons is produced in an excited state and decays to a ground state tau lepton and a photon. The event selection consists of two isolated tau lepton decay candidates and a high-energy photon. The mass of the excited tau lepton is reconstructed using the missing transverse momentum in the event, assuming the momentum of the neutrinos from each tau lepton decay are aligned with the visible decay products. No excess of events above the standard model background prediction is observed. This null result is used to set lower bounds on the excited tau lepton mass. For a compositeness scale equal to the excited tau lepton mass, excited tau leptons with masses below 4700 GeV are excluded at 95% confidence level; for = 10 TeV this exclusion is set at 2800 GeV. This is the first experimental result covering this production and decay process in the excited tau mass range above 175 GeV
Evidence for similar collectivity of high transverse momentum particles in pPb and PbPb collisions
No full textInternational audienceCharged hadron elliptic anisotropies () are presented over a wide transverse momentum () range for proton-lead (pPb) and lead-lead (PbPb) collisions at nucleon-nucleon center-of-mass energies of 8.16 and 5.02 TeV, respectively. The data were recorded by the CMS experiment and correspond to integrated luminosities of 186 nb and 0.607 nb for the pPb and PbPb systems, respectively. A four-particle cumulant analysis is performed using subevents separated in pseudorapidity to effectively suppress non-collective effects. At high ( 8 GeV), significant positive values are observed that are similar between pPb and PbPb collisions at comparable charged particle multiplicities. This observation suggests a common origin for the multi-particle collectivity for high- particles in the two systems