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Next Generation Multi-element monolithic Germanium detectors for Spectroscopy: First integration at ESRF facility
No full textInternational audienceThe XAFS-DET work package of the European LEAPS-INNOV project is developing a high-purity Germanium detectors for synchrotron applications requiring spectroscopic-grade response. The detectors integrate three key features: (1) newly designed monolithic Germanium sensors optimised to mitigate charge-sharing events, (2) an improved cooling and mechanical design structure supported by thermal simulations, and (3) complete electronic chain featuring a low-noise CMOS technology-based preamplifier. enabling high X-ray count rate capability over a broad energy range (5-100 keV). This paper discusses the first integration and characterization of one of the two multi-element Ge detectors at the European Synchrotron Radiation Facility (ESRF). The integration phase included validating high-throughput front-End electronics, integrating them with the Ge sensor, and operating them at liquid nitrogen temperature, in addition to the experimental characterization, which consists of electronics noise study and spectroscopic performance evaluation
Configurational Energy as a Microstructural Descriptor of Failure Precursors in 2D Frictional Granular Materials
No full textInternational audienceLocalized deformation in dense granular materials, often culminating in the formation of shear bands, is a key failure mechanism in geotechnical and material systems. However, predicting the onset of such localization remains a fundamental challenge due to the system's inherent inelasticity and microstructural complexity. In this study, we propose that the evolution of internal configuration—characterized by changes in contact topology and stored potential energy—governs the collective mechanical response and encodes precursors to material failure. To quantify this evolving internal state, we introduce the notion of configurational energy, defined as the change in contact‐scale elastic potential energy resulting from a controlled loading—unloading probe. This metric is first formulated at the contact level and subsequently analyzed at the specimen scale using Discrete Element Method (DEM) simulations of biaxial compression. Our results demonstrate that configurational energy captures the system's sensitivity to perturbations and reflects local instability: both positive and negative values emerge at the contact level, with large magnitudes concentrated near regions of active rearrangement. Despite this local variability, the specimen‐scale configurational response remains strictly negative, and its magnitude increases systematically as the material approaches failure. Notably, spatial localization of configurational energy precedes the formation of macroscopic shear bands with an evolving internal length scale, offering a mesoscale energetic signature of incipient failure. These findings establish configurational energy as a physically grounded descriptor of microstructural evolution and a promising tool for anticipating failure in frictional granular systems
Determining the optimal operating conditions of SOFCs electrolytes based on evolution of their electronic transport number with temperature and oxygen partial pressure: A case study of the Ce0.9Gd0.1O2-δ electrolyte
No full textInternational audienceOptimizing the performance of Solid Oxide Fuel Cells (SOFCs) or Solid Oxide Electrolysis Cells (SOECs) necessitates a thorough understanding of the electrolytes' transport properties under the device's operating conditions, whether through experimental data or established transport laws. This study investigates the electrical properties of Gd-doped ceria as a potential electrolyte material for SOFC applications. The electrical behavior of Gd-doped ceria was analyzed over a broad range of oxygen partial pressures (from 10−36 to 1 bar) and temperatures (200 °C to 900 °C) to establish the Patterson diagram, i.e., the variation of the total electrical conductivity as a function of the oxygen partial pressure (on logarithmic scales) for various temperatures. Additionally, the average transport number of the Gd-doped ceria electrolyte was evaluated under varying oxygen partial pressure gradients and temperatures using a specific semi-permeation method and compared with data derived from the Patterson diagram. The results collected in this study indicate that the use of Gd-doped ceria as an SOFC electrolyte requires precise control of oxygen partial pressure (particularly below 10−24 bar at 600 °C) or the hydrogen-to-water ratio at the hydrogen electrode to prevent efficiency degradation of the electrochemical system and to determine optimal operating conditions.</p
Using thin AZO layers coupled with SiNx:H as a way to decrease Indium consumption in SHJ cells and modules
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Préface e-N TEXTE-]S—On[-iMAGE / hommage à Claude Rutault
No full textInternational audienceQuand nous avons imaginé cet ouvrage collectif poursuivant les différents points d’interrogations soulevés pendant le colloque TEXTE & IMAGE 6 — Pour un nouveau contrat social de l’errance : entre Art[S], Territoire[S], Blockchain[S] et Crypto- monnaie[S] — qui s’était déroulé à La Valette2 en 2021, nous pensions encore avoir le temps. Le temps de développer avec Claude Rutault une extension de sa Définition / Méthode 169 AMZ par rapport à la blockchain ; le temps de vous offrir avec cette extension que nous avions intitulée [AMZ] U-P — avec un petit smiley nous tirant la langue — comme un pied de nez offert à la postérité autour de l’œuvre de cet artiste majeur de la fin du XXe siècle..
A model-independent measurement of the CKM angle in the decays and ()
No full textInternational audienceA model-independent determination of the CKM angle is presented, using the and decays, with . This measurement is the first phase-space-binned study of these decay modes, and uses a sample of proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of fb. The phase-space bins are optimised for sensitivity to , and in each bin external inputs from the BESIII experiment are used to constrain the charm strong-phase parameters. The result of this binned analysis is , where the uncertainty includes both statistical and systematic contributions. Furthermore, when combining with existing phase-space-integrated measurements of the same decay modes, a value of is obtained, which is one of the most precise determinations of to date
Fine sediment production during urban development: the damage is done early!
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Search for planetary-mass ultra-compact binaries using data from the first part of the LIGO--Virgo--KAGRA fourth observing run
No full textInternational audienceWe present a search for gravitational waves from inspiraling, planetary-mass ultra-compact binaries using data from the first part of the fourth observing run of LIGO, Virgo and KAGRA. Finding no evidence of such systems, we determine the maximum distance reach for such objects and their merger rate densities, independently of how they could have formed. Then, we identify classes of primordial black-hole mass distributions for which these rate limits can be translated into relevant constraints on the mass distribution of primordial black holes, assuming that they compose all of dark matter, in the mass range . Our constraints are consistent with existing microlensing results in the planetary-mass range, and provide a complementary probe to sub-solar mass objects
Tracking S-matrix bounds across dimensions
No full textInternational audienceWe study massive scattering of identical scalar particles in spacetime dimensions 3 to 11 using non-perturbative S-matrix bootstrap techniques. Treating as a continuous parameter, we compute two-sided numerical bounds on low-energy observables and find smooth branches of extremal amplitudes separated by sharp kinks at and , coinciding with a transition in threshold analyticity and the loss of some well-known dispersive positivity constraints. Our results reveal a rich structure in the space of massive S-matrices across dimensions and identify threshold singularities as a key organizing principle. We comment on numerical limitations at large dimension and on possible implications for ultraviolet completion in higher-dimensional quantum field theory
About the link between lab-measured material properties and whole building performance simulation: Application to bio-stabilized rammed earth
No full textInternational audienceThis article aims to investigate the link between lab-measured material properties and whole building performance of rammed earth (RE) walls through characterization at laboratory scale and numerical simulations using combined heat and moisture transfer models at whole building (WB) scale. RE buildings are known as an energy-efficient solution in hot climates and are low-carbon construction since local unfired earth is used as construction material. Nevertheless, the behavior of such buildings under different internal and external loads needs additional investigations. The present study explores the use of unstabilized RE walls, with and without the use of painting, three bio-stabilized RE and conventional concrete walls for comparison. The simulation includes climate conditions from Central Europe and North Africa, along with typical residential and tertiary occupancy scenarios. To identify the contribution of RE materials in controlling the indoor climate, the investigation covers a total of 24 configurations of six wall materials, two locations, and two occupancy scenarios. Results are analyzed by comparing heating demand, summer thermal comfort, and relative humidity levels. Furthermore, the hygrothermal properties of bio-stabilized RE are experimentally determined, to confirm the choice of using only moisture-dependent parameters. Experimental investigations focus on the influence of temperature on sorption isotherm, hysteresis, adsorption kinetics, and moisture buffer value (MBV). The results of this investigation show that thermal properties measured at the material scale seem to have a direct link with results at the whole building scale for heating demand and summer thermal comfort for uninsulated walls, while a more complex behavior is related to the hygroscopic properties, due mainly to the combined effect of the kinetics of adsorption and vapor permeability of the material