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GWTC-4.0: Constraints on the Cosmic Expansion Rate and Modified Gravitational-wave Propagation
No full textInternational audienceWe analyze data from 142 of the 218 gravitational-wave (GW) sources in the fourth LIGO-Virgo-KAGRA Collaboration (LVK) Gravitational-Wave Transient Catalog (GWTC-4.0) to estimate the Hubble constant jointly with the population properties of merging compact binaries. We measure the luminosity distance and redshifted masses of GW sources directly; in contrast, we infer GW source redshifts statistically through i) location of features in the compact object mass spectrum and merger rate evolution, and ii) identifying potential host galaxies in the GW localization volume. Probing the relationship between source luminosity distances and redshifts obtained in this way yields constraints on cosmological parameters. We also constrain parameterized deviations from general relativity which affect GW propagation, specifically those modifying the dependence of a GW signal on the source luminosity distance. Assuming our fiducial model for the source-frame mass distribution and using GW candidates detected up to the end of the fourth observing run (O4a), together with the GLADE+ all-sky galaxy catalog, we estimate km s Mpc. This value is reported as a median with 68.3% (90%) symmetric credible interval, and includes combination with the measurement from GW170817 and its electromagnetic counterpart. Using a parametrization of modified GW propagation in terms of the magnitude parameter , we estimate , where recovers the behavior of general relativity
AI-enabled evolution: unveiling the synergy between manufacturing and services through coordination and integration
No full textInternational audienceCoordination and integration are fundamental pillars of modern supply chains, within which manufacturing and service operations function as two core components. Recently, the growing availability of data, coupled with rapid advances in artificial intelligence (AI), has significantly accelerated the adoption of AI technologies across manufacturing and service domains. Against this backdrop, we completed a special issue titled “AI-Enabled Evolution: Unveiling the Synergy between Manufacturing and Services through Coordination and Integration” to showcase the latest developments in this domain. In this editorial, we first outline the background and review existing literature on AI applications in operations management. We then present the papers included in this issue, highlighting how various AI techniques are applied across manufacturing and service contexts, encompassing performance improvement and sustainability advancement, optimisation and decision-making framework development, as well as applications in logistics, scheduling, and risk management. Finally, we conclude by identifying promising avenues for future research
Adaptive gradient domain normalization for one-sided unsupervised medical image synthesis
No full textInternational audienc
Expanding the application of the TAIL rating scheme to schools: schoolTAIL
No full textInternational audienceSchools have no universally adopted scheme for rating indoor environmental quality (IEQ). In this work, we adapted the TAIL rating scheme that was developed for assessing IEQ in offices and hotels so that it can be used in schools. The original TAIL scheme assesses thermal, acoustic, and luminous conditions, along with indoor air quality, using ten measured parameters and one evaluated through observation and one through simulation. We supplemented it with two other parameters, reverberation time and the concentration of nitrogen dioxide, to adequately characterize a classroom's IEQ. We have also updated the ranges for PM2.5 in accordance with the latest updates to the WHO air quality guidelines. Otherwise, we kept the principles used to develop the original TAIL rating scheme unchanged. We used measurements from schools reported in the published literature to identify the relevant parameters. We refer to the newly developed scheme as TAIL for schools, in short, schoolTAIL. We examined its feasibility using an existing database, with measurements made in 308 randomly selected schools as part of a nationwide survey in France. The new scheme turned out to be a valuable tool for identifying potential problems and prioritizing IEQ remediations, providing a comprehensive yet easy-tounderstand overview of the current situation in school buildings
Probing gluon saturation with forward di-hadron correlations in proton-nucleus collisions
No full textInternational audienceWe present a detailed numerical investigation of semi-inclusive forward di-hadron production in proton-nucleus collisions employing the Color Glass Condensate effective theory. We focus on the regime where di-hadrons are produced nearly back-to-back in the transverse plane, thereby justifying a transverse-momentum-dependent factorization approach in terms of small- gluon distributions. Our computation integrates several key elements: i) non-linear rapidity evolution via the Balitsky-Kovchegov equation with running coupling, ii) both perturbative and non-perturbative Sudakov resummation, and iii) a phenomenologically constrained model for the initial conditions for small- gluon distributions. We compare this phenomenological framework to experimental data from the STAR Collaboration on azimuthal correlations in forward di-pion production in both proton-proton and proton-gold collisions. We analyze the systematic theoretical uncertainties associated with the saturation scales of nuclei at the initial scale for rapidity evolution and with those associated with the hadronization process. Finally, we make predictions for the kinematics anticipated to be covered by the ALICE Forward Calorimeter (FoCal) upgrade at the Large Hadron Collider
Assessment of the tritium analysis performance of a nonylphenol-ethoxylate-free liquid scintillator by interlaboratory comparison
No full textInternational audienceWith a view to using liquid scintillators compliant with the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations, some laboratories have expressed an interest in testing the ProSafe LT+ , a liquid scintillator without nonylphenol-ethoxylates (NPE). In order to evaluate the impact of using this new liquid on the analysis results, the CETAMA consortium organised two interlaboratory comparisons. Two ranges of tritium activity were selected to meet the needs of environmental and waste monitoring. 23 laboratories took part in these exercises, comparing results obtained with Prosafe LT+ to those obtained with NPE-containing liquid scinitllators. From the results it was seen that the background and the background noise obtained with the nonylphenol-ethoxylates-free liquid scintillator are not significantly different from that of the usual liquid scintillator, whether for the waste or environmental domain, over short (15 min) or long (200 min) counting times. Furthermore, the decision threshold and the detection limit values estimated with ProSafe LT+ were no different from those of usual scintillators. However, for the measurement of samples, and particularly for samples with a tritium activity above 15 Bq/kg, the ProSafe LT+ presented a reduced measurement quality compared to the nonylphenol-ethoxylates-containing LS i.e. the measurement uncertainty obtained with ProSafe LT+ is systematically higher. In light of the results obtained through this study, the authors recommend the use of the ProSafe LT+ with the proviso that the deterioration in measurement uncertainty be taken into account and found to be compatible with a laboratory’s individual needs
Linear Effects, Exceptions, and Resource Safety: A Curry-Howard Correspondence for Destructors
No full textDraft pre-printInternational audienceWe analyse the problem of combining linearity, effects, and exceptions, in abstract models of programming languages, as the issue of providing some kind of strength for a monad in a linear setting. We consider in particular for the \emph{allocation monad}, which we introduce to model and study resource-safety properties. We apply these results to a series of two linear effectful calculi for which we establish their resource-safety properties. The first calculus is a linear call-by-push-value language with two allocation effects new and delete. The resource-safety properties follow from the linear (and even ordered) character of the typing rules. We then explain how to integrate exceptions on top of linearity and effects by adjoining default destruction actions to types, as inspired by C++/Rust destructors. We see destructors as objects in the slice category over . This construction gives rise to a second calculus, an \emph{affine} ordered call-by-push-value language with exceptions and destructors, in which the weakening rule performs a side-effect. As in C++/Rust, a ``move'' operation is necessary to allow random-order release of resources, as opposed to last-in-first-out order. Moving resources is modelled as an exchange rule that performs a side-effect
Towards the Giant Radio Array for Neutrino Detection (GRAND): the GRANDProto300 and GRAND@Auger prototypes
No full textInternational audienceThe Giant Radio Array for Neutrino Detection (GRAND) is a proposed multi-messenger observatory of ultra-high-energy (UHE) particles of cosmic origin. Its main goal is to find the long-sought origin of UHE cosmic rays by detecting large numbers of them and the secondary particles created by their interaction -- gamma rays, and, especially, neutrinos. GRAND will do so using large arrays of radio antennas that look for the radio signals emitted by the air showers initiated by the interactions of the UHE particles in the atmosphere. Since 2023, three small-scale prototype GRAND arrays have been in operation: GRAND@Nançay in France, GRAND@Auger in Argentina, and GRANDProto300 in China. Together, their goal is to validate the detection principle of GRAND under prolonged field conditions, achieving efficient, autonomous radio-detection of air showers. We describe the hardware, software, layout, and operation of the GRAND prototypes and show the first radio spectra measured by them. Despite challenges, the successful operation of the prototypes confirms that the GRAND instrumentation is apt to address the goals of the experiment and lays the groundwork for its ensuing stages
Measurement of correlations between elliptic flow and mean transverse momentum in pp, p-Pb, and Pb-Pb collisions at the LHC
No full textInternational audienceMeasurements of the event-by-event correlation between elliptic flow () and the mean transverse momentum () using the modified Pearson correlation coefficient are reported in pp collisions at TeV, and in p-Pb and Pb-Pb collisions at a center-of-mass energy per nucleon pair TeV. This analysis is based on the full LHC Run 2 dataset recorded by ALICE and is performed for the first time in small collision systems with the ALICE detector. In Pb-Pb collisions, the measurement shows a non-monotonic dependence on charged particle multiplicity (); it first decreases and then increases with an increase in multiplicity. The decreasing trends of with increasing multiplicity are also observed in p-Pb and pp collisions for the presented multiplicity range. All three systems show consistent values of for . These measurements are also compared with theoretical model calculations, including PYTHIA, where no collectivity is generated, as well as AMPT and IP-Glasma + MUSIC + UrQMD, which produce collective effects in small systems. These comparisons offer unique insights into the origin of collectivity in small systems. They improve the understanding of the initial geometry, size, and their correlations. The comparison also allows an investigation of the role of initial momentum correlations predicted by the Color Glass Condensate framework. The new measurements could not be explained by current state-of-the-art models, offering insights into the initial stage of collisions in small systems and also imposing strong constraints on the existing theoretical models. This will significantly advance our understanding of the collective phenomena observed in small systems at the LHC
Jet energy loss in anisotropic plasmas meets limiting attractors
No full textInternational audienceWe consider the energy loss of a high-energy parton in the early anisotropic plasma in heavy-ion collisions. Working in the harmonic approximation, we compute the change in the mean energy of an emitted gluon in the presence of an anisotropic background, characterized by anisotropic jet quenching parameters . Evaluating the resulting integrals numerically, we compare with isotropic media, and obtain a simple pocket formula to estimate the impact of anisotropy on the mean emitted gluon energy, which is generally small. We then combine our results with the values of the jet quenching parameter extracted from QCD kinetic theory simulations and show that the medium length dependence of this mean energy loss exhibits the characteristics of limiting attractors, which can be obtained by extrapolating to zero and infinite coupling. Our study thus relates energy loss of jet partons to universal dynamics of anisotropic plasmas