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Evidence of different -baryon and D-meson elliptic flow in PbPb collisions at = 5.36 TeV with ALICE at the LHC
No full textInternational audienceThe ALICE collaboration reports the azimuthal-anisotropy coefficient of prompt D, D, D mesons and the first measurement of of prompt baryons in semicentral PbPb collisions at a center-of-mass energy per nucleon pair of TeV. The D mesons and baryons are reconstructed in their hadronic decays at midrapidity () in the transverse-momentum interval GeV/. Similar values are measured for D and D, while a hint of a difference () emerges between D and D mesons in the GeV/ interval. A larger for baryons with respect to D mesons is observed with significance for GeV/, providing evidence for the partonic origin of charm-hadron and hadron formation via quark coalescence. This interpretation is further supported by comparisons with theoretical calculations of charm-quark transport in a hydrodynamically expanding medium
Effects of an unsynchronized RTS attack on a hardware 802.11ah test bed
No full textInternational audienceWi-Fi HaLow is expected to play a pivotal role inIoT 2.0; however, its increasing adoption makes it an attractivetarget for cyber adversaries. Enabling more than 8,000 deviceson a single deployment, Wi-Fi HaLow awakens the possibility ofmassive network creation along 1 km distances. Unfortunately,attackers can easily take advantage of this extensive reach.Current research shows how an RTS attack, a MAC sub-layerattack, can shut down the communication exchange of an entireWi-Fi HaLow network, yet no real test bed implementation hasbeen done. This is the first article that studies the effects of anunsynchronized RTS attack on a hardware-implemented Wi-FiHaLow network. The results show that the STA can not detectthe attack based on the metrics and the attack has an impact of95.7% at the physical layer and a 4.3% at the MAC sub-layer
The Online Data Filter for the KM3NeT Neutrino Telescopes
No full textInternational audienceThe KM3NeT research infrastructure comprises two neutrino telescopes located in the deep waters of the Mediterranean Sea, namely ORCA and ARCA. KM3NeT/ORCA is designed for the measurement of neutrino properties and KM3NeT/ARCA for the detection of high\nobreakdashes-energy neutrinos from the cosmos. Neutrinos are indirectly detected using three\nobreakdashes-dimensional arrays of photo\nobreakdashes-sensors which detect the Cherenkov light that is produced when relativistic charged particles emerge from a neutrino interaction. The analogue pulses from the photo\nobreakdashes-sensors are digitised offshore and all digital data are sent to a station on shore where they are processed in real time using a farm of commodity servers and custom software. In this paper, the design and performance of the software that is used to filter the data are presented. The performance of the data filter is evaluated in terms of its purity, capacity and efficiency. The purity is measured by a comparison of the event rate caused by muons produced by cosmic ray interactions in the Earth's atmosphere with the event rate caused by the background from decays of radioactive elements in the sea water and bioluminescence. The capacity is measured by the minimal number of servers that is needed to sustain the rate of incoming data. The efficiency is measured by the effective volumes of the sensor arrays
Quantum vs. semiclassical description of in-QGP quarkonia in the quantum Brownian regime
No full textInternational audienceIn this work, we explore the range of validity of the semiclassical approximation of a quantum master equation designed to describe the dynamics in a quark gluon plasma at various temperatures, in the quantum Brownian regime. We perform a comparative study of various properties, e.g. the charmonia yield, of the Wigner density obtained with the Lindblad equation and with the associated semiclassical Fokker-Planck equation. The semiclassical description is found to reproduce with a remarkable accuracy the results obtained through the full quantum description. We show that, to a large extent, this can be attributed to the non-unitary components of the dynamics that result from the contact of the subsystem with the thermal bath, leading to a rapid classicalization of the subsystem
Automated multimodal severity assessment of diabetic retinopathy using ultra-widefield color fundus photography and clinical tabular data
No full textInternational audienceThis study introduces an automatic deep-learning-based approach to diabetic retinopathy (DR) severity assessment by integrating two modalities: Ultra-Widefield Color Fundus Photography (UWF-CFP) from the CLARUS 500 device (Carl Zeiss Meditec Inc., Dublin, CA, USA) and a comprehensive set of clinical data from the EVIRED project. We propose a framework that combines the information from 2D UWF-CFP images and a set of 76 tabular features, including demographic, biochemical, and clinical parameters, to enhance the classification accuracy of DR stages. Our model uses advanced machine learning techniques to address the complexities of synthesizing heterogeneous data types, providing a holistic view of patient health status. Results indicate that this fusion outperforms traditional methods that rely solely on imaging or clinical data, suggesting a robust model which can provide practitioners with a supportive second opinion on DR severity, particularly useful in screening workflows. We measured a multiclass accuracy of 63.4% and kappa of 0.807 for our fusion model which is 2.1% higher in accuracy and 0.022 higher in kappa compared to the image unimodal classifier. Several interpretation methods are used to provide practitioners with an inside view of the workings of classification methods and allow them to discover the most important clinical features
Ultra-pure Nickel for Structural Components of Low-Radioactivity Instruments
No full textInternational audienceThe next generation of rare-event search experiments in nuclear and particle physics demand structural materials combining exceptional mechanical strength with ultra-low levels of radioactive contamination. This study evaluates chemical vapor deposition (CVD) nickel as a candidate structural material for such applications. Manufacturer-supplied CVD Ni grown on aluminum substrates underwent tensile testing before and after welding alongside standard Ni samples. CVD Ni exhibited a planar tensile strength of ~600 MPa, significantly surpassing standard nickel. However, welding and heat treatment were found to reduce the tensile strength to levels comparable to standard Ni, with observed porosity in the welds likely contributing to this reduction. Material assay via inductively coupled plasma mass spectrometry (ICP-MS) employing isotope-dilution produced measured bulk concentration of 232-Th, 238-U, and nat-K at the levels of ~70 ppq, <100 ppq, and ~900 ppt, respectively, which is the lowest reported in nickel. Surface-etch profiling uncovered higher concentrations of these contaminants extending ~10 micrometer beneath the surface, likely associated with the aluminum growth substrate. The results reported are compared to the one other well documented usage of CVD Ni in a low radioactive background physics research experiment and a discussion is provided on how the currently reported results may arise from changes in CVD fabrication or testing process. These results establish CVD Ni as a promising low-radioactivity structural material, while outlining the need for further development in welding and surface cleaning techniques to fully realize its potential in large-scale, low radioactive background rare-event search experiments
Muon tracking in a LiquidO opaque scintillator detector
No full textInternational audienceLiquidO is an innovative radiation detector concept. The core idea is to exploit stochastic light confinement in a highly scattering medium to self-segment the detector volume. In this paper, we demonstrate event-by-event muon tracking in a LiquidO opaque scintillator detector prototype. The detector consists of a 30 mm cubic scintillator volume instrumented with 64 wavelength-shifting fibres arranged in an 88 grid with a 3.2 mm pitch and read out by silicon photomultipliers. A wax-based opaque scintillator with a scattering length of approximately 0.5 mm is used. The tracking performance of this LiquidO detector is characterised with cosmic-ray muons and the position resolution is demonstrated to be 450 m per row of fibres. These results highlight the potential of LiquidO opaque scintillator detectors to achieve fine spatial resolution, enabling precise particle tracking and imaging
The Governance of French Political Biographies: Mapping Content Control and Editorial Authority on Wikipedia
No full textInternational audienceAs Wikipedia has become a space for the construction of political reputation, the governance of its biographical content has emerged as a critical concern for political communication and democratic integrity. While previous scholars have largely focused on edit wars, this paper proposes a shift toward the mechanisms of content control. We operationalize this control through a systematic analysis of revert interventions, investigating how editorial authority is distributed across contributors and whether these governance structures vary across distinct political fields. Utilizing a longitudinal dataset of 723,233 revisions to 2,837 Wikipedia biographical entries for French legislative candidates (2002–2024), we categorize these profiles into ideological clusters (e.g., left, center-right, far-right,etc.). To contextualize these quantitative findings, we adopt a mixed-methods approach complementing our analysis with semi-structured interviews conducted with seven of the fifty most active contributors within these clusters. Across all political clusters, we find that content control via revert interventions is highly unequal: a small fraction of contributors accounts for a disproportionate share of interventions, reflecting a general concentration of editorial authority. Moving beyond this aggregate distribution, we show however that the organization of content control differs concretely across political fields. Center-right and mainstream right clusters combine high volumes of content control with relatively broad and stable cores, indicating a pluralized governance where authority is exercised by a structured group rather than monopolized by a single actor. Whereas far-right pages exhibit a contrasting configuration that we characterize as high-alert governance where content control is concentrated within a small group of editors, yet labor is relatively evenly shared among them. Left-wing clusters, by comparison, display lower volumes of revert-based intervention and weaker stabilization of control roles. Deeper analysis highlights that governance is editor-centered but field-bounded, meaning that core controllers frequently intervene across multiple pages and sometimes across adjacent political clusters, rejecting a strictly page-local conception of governance, while stopping short of a single platform-wide elite. Qualitative interviews further elucidate these patterns by the identification of two primary editorial profiles. First are the political enthusiasts, whose interventions are motivated by intense monitoring of political news and a desire for ‘objectivity’, and generalist patrollers focused on broader platform maintenance and surveillance. Ultimately, we demonstrate that these divergent governance architectures are driven by two primary factors: the intensity of ideological contestation surrounding a page and the varying degrees of political activism among contributors. While the ‘high-alert’ configurations of far-right pages are associated with a higher potential for controversy and sustained vigilance, left-wing clusters are more often governed through diffuse and intermittent interventions carried out by generalist patrollers rather than stabilized enforcement cores. These findings reveal that while most revert-based interventions are carried out in the name of platform norms such as neutrality and verifiability, contributors nevertheless interpret and apply these norms in context-dependent ways. Qualitative evidence indicates that political sensitivity, media salience, and individual engagement levels shape how and when editors intervene, without reducing that governance to coordinated militant bias
Design of a high voltage delivery system for noble liquid time projection chambers
No full textInternational audienceNoble liquid time projection chambers (TPCs) are a leading technology in the detection of ionizing radiation, particularly in applications such as accelerator neutrino physics, dark matter detection, and neutrinoless double beta decay. This paper addresses the design considerations for implementing stable high voltage (HV) systems within large noble liquid TPCs, with a focus on the nEXO experiment. Utilizing insights from prior HV research and experimental investigations, we outline factors influencing HV stability and discuss design choices to improve stability and prevent electrical discharges. A novel HV delivery system concept is presented, tailored for the nEXO TPC, which incorporates these design considerations while also meeting the stringent radiopurity requirements of the nEXO neutrinoless double beta decay search. These design considerations and their specific implementation towards a HV delivery system offer guidance to future experiments applying high voltage in noble liquid environments
The influence of virtual character actions and emotional expressions on trust in autonomous vehicles
No full textInternational audienceWith the rapid advancement of Autonomous Vehicle (AV) technology, improving user trust is critical to realizing its full potential. This study introduces a Virtual Character (VC) as an assistant for passengers, designed to enhance trust in AVs. The VC acts as an interactive guide, providing feedback and emotional cues to capture passengers’ attention during uncertain situations. To assess its impact on trust, Situation Awareness (SA), and acceptability, we integrated the VC into a Virtual Reality-simulated AV environment. Thirty-six participants experienced four conditions: a static VC, an emotion-only VC, an action-only VC, and a combined action–emotion VC. Results show that incorporating a VC can enhance user trust, SA, and acceptance of AV technologies. VC actions have a stronger effect on trust than emotional expressions, while emotional cues alone have the potential to reduce stress. Notably, participants preferred a VC that combines both action and emotion. These findings highlight the value of integrating expressive and behavior-rich VCs into AV interfaces to communicate system awareness, reduce uncertainty, and strengthen passenger trust