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Search for heavy resonances decaying into two Higgs bosons in the final state in proton-proton collisions at = 13 TeV
No full textInternational audienceA search is presented for massive narrow-width resonances in the mass range of 14.5 TeV, decaying into pairs of Higgs bosons (HH). The search uses proton-proton collision data at a center-of-mass energy of 13 TeV collected with the CMS detector at the CERN LHC during 20162018, corresponding to an integrated luminosity of 138 fb. The analysis targets final states where one Higgs boson decays into a pair of bottom quarks and the other into a pair of tau leptons, X HH . It uses a single large jet to reconstruct the H decay, while the H decay products can either be contained within a single large jet or appear as two isolated tau leptons. The observed data are consistent with standard model background expectations. Upper limits at 95% confidence level are set on the production cross section for resonant HH production for masses between 1 and 4.5 TeV. This analysis sets the most sensitive limits to date on X HH decays in the mass range of 1.4 to 4.5 TeV
A robust computational framework for the mixture-energy-consistent six-equation two-phase model with instantaneous mechanical relaxation terms
No full textWe present a robust computational framework for the numerical solution of a hyperbolic 6-equation single-velocity two-phase system. The system's main interest is that, when combined with instantaneous mechanical relaxation, it recovers the solution of the 5-equation model of Kapila. Several numerical methods based on this strategy have been developed over the years. However, neither the 5- nor 6-equation model admits a complete set of jump conditions because they involve non-conservative products. Different discretizations of these terms in the 6-equation model exist. The precise impact of these discretizations on the numerical solutions of the 5-equation model, in particular for shocks, is still an open question to which this work provides new insights. We consider the phasic total energies as prognostic variables to naturally enforce discrete conservation of total energy and compare the accuracy and robustness of different discretizations for the hyperbolic operator. Namely, we discuss the construction of an HLLC approximate Riemann solver in relation to jump conditions. We then compare an HLLC wave-propagation scheme which includes the non-conservative terms, with Rusanov and HLLC solvers for the conservative part in combination with suitable approaches for the non-conservative terms. We show that some approaches for the discretization of non-conservative terms fit within the framework of path-conservative schemes for hyperbolic problems. We then analyze the use of various numerical strategies on several relevant test cases, showing both the impact of the theoretical shortcomings of the models as well as the importance of the choice of a robust framework for the global numerical strategy
Prompt Searches for Very-high-energy γ-Ray Counterparts to IceCube Astrophysical Neutrino Alerts
No full textInternational audienceThe search for sources of high-energy astrophysical neutrinos can be significantly advanced through a multimessenger approach, which seeks to detect the γ-rays that accompany neutrinos as they are produced at their sources. Multimessenger observations have so far provided the first evidence for a neutrino source, illustrated by the joint detection of the flaring blazar TXS 0506+056 in high-energy (E > 1 GeV) and very-high-energy (VHE; E > 100 GeV) γ-rays in coincidence with the high-energy neutrino IceCube-170922A, identified by IceCube. Imaging atmospheric Cherenkov telescopes (IACTs), namely FACT, H.E.S.S., MAGIC, and VERITAS, continue to conduct extensive neutrino target-of-opportunity follow-up programs. These programs have two components: follow-up observations of single astrophysical neutrino candidate events (such as IceCube-170922A), and observation of known γ-ray sources after the identification of a cluster of neutrino events by IceCube. Here we present a comprehensive analysis of follow-up observations of high-energy neutrino events observed by the four IACTs between 2017 September (after the IceCube-170922A event) and 2021 January. Our study found no associations between γ-ray sources and the observed neutrino events. We provide a detailed overview of each neutrino event and its potential counterparts. Furthermore, a joint analysis of all IACT data is included, yielding combined upper limits on the VHE γ-ray flux
Strategy and performance of the CMS long-lived particle trigger program in proton-proton collisions at = 13.6 TeV
No full textInternational audienceIn the physics program of the CMS experiment during the CERN LHC Run 3, which started in 2022, the long-lived particle triggers have been improved and extended to expand the scope of the corresponding searches. These dedicated triggers and their performance are described in this paper, using several theoretical benchmark models that extend the standard model of particle physics. The results are based on proton-proton collision data collected with the CMS detector during 20222024 at a center-of-mass energy of 13.6 TeV, corresponding to integrated luminosities of up to 123 fb
Combination of searches for heavy vector boson resonances in proton-proton collisions at = 13 TeV
No full textInternational audienceA combined statistical analysis of searches for heavy vector boson resonances decaying into pairs of W, Z, or Higgs bosons, as well as into quark pairs (, , , ) or lepton pairs (, ), with e, , , is presented. The results are based on proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb, collected by the CMS experiment from 2016 to 2018. No significant deviation from the expectations of the standard model is observed. The results are interpreted in the simplified heavy vector triplet (HVT) framework, setting 95% confidence level upper limits on the production cross sections and coupling strengths to standard model particles or the HVT bosons. The results exclude HVT resonances with masses below 5.5 TeV in a weakly coupled scenario, below 4.8 TeV in a strongly coupled scenario, and up to 2.0 TeV in the case of production via vector boson fusion. The combination provides the most stringent constraints to date on new phenomena predicted by the HVT model
Sanitizable Signatures with Different Admissibility Policies for Multiple Sanitizers
No full textThe full version of a publication in AsiaCCS 2026.International audienceSanitizable signatures authorize semi-trusted sanitizers to modify admissible blocks of a signed message. Most works consider only one sanitizer while those considering multiple sanitizers are limited by their capacity to manage admissible blocks which must be the same for all of them. We study the case where different sanitizers with different roles can be trusted to modify different blocks of the message. We define a model for multi-sanitizer sanitizable signatures which allow managing authorization for each sanitizer independently. We also provide formal definitions of its security properties. We propose two secure generic constructions FSV-k-SAN and IUT-k-SAN with different security properties. We implement both constructions and evaluate their performance on a server and a smartphone
Analysis of French Spirit Barrels (Oak Wood) Metabolites by LDI-MSI
No full textInternational audienceInsight into the composition, migration, degradation, and external interactions of compounds within oak is fundamental to the wine and spirits industry, given their direct impact on the organoleptic properties of aged spirits. The characterization of oak extracts has traditionally relied on HPLC-MS and GC-MS. However, (MA)LDI-MS imaging is a technique that could give newinformation about wood metabolite distribution.IntroductionCognac barrels are primarily made of oak wood (Quercus spp.), a genus within the Fagaceae family that includes approximately 500 species. Understanding the composition, migration, degradation, and external interactions of compounds in oak is essential for the wine and spirits industry, as these processes directly influence the organoleptic properties of aged spirits. Oak extracts have been widely studied using techniques such as HPLC-MS1 and GC-MS2, while more recent work has used TOF-SIMS3 to analyze small surface regions of barrel staves. Although TOFSIMS offers high spatial resolution, it is limited in mass range and mass resolution.(1) Glabasnia, A.; Hofmann, T. Identification and Sensory Evaluation of Dehydro- and Deoxyellagitannins Formed upon Toasting of Oak Wood (Quercus alba L.). J. Agric. Food Chem. 2007, 55 (10), 4109–4118. DOI: 10.1021/jf070151m.(2) Flamini, R.; Panighel, A.; Marchi, F. de. Mass spectrometry in the study of wood compounds released in the barrel‐aged wine and spirits. Mass Spectrometry Reviews 2023, 42 (4), 1174–1220. DOI: 10.1002/mas.21754.(3) Cournut, A.; Vanbellingen, Q. P.; Demaye, A.; Ochs, M.; Römpp, A.; Touboul, D.; Eparvier, V.; Brunelle, A. Multimodal Analysis of Oak Wood Metabolites for a Comprehensive Understanding of the Aging Process in Typical French Spirit Barrels. Journal of mass spectrometry : JMS 2025, 60 (9), e5170. DOI: 10.1002/jms.5170.MethodsWe analyzed the transversal surface of oak staves, from the inner to the outer barrel wall, enabling the observation of gradual chemical changes across the entire wood section. We compared freshly cut, freshly toasted, and historical (100-year-old) staves. For our studies, we utilized a MALDI source equipped with autofocus and large sample holders, allowing the direct analysis of intact samples (2.0×0.3×0.5 cm).ResultsPreliminary results revealed a decrease in ion signal intensity in the inner and/or outer regions of the barrel. Several experimental strategies (including changes in acquisition direction, the use of internal standards, and optimization of instrumental parameters) were tested to determine whether this effect reflected true chemical variation or methodological limitations. Colocalization analysis using MZmine proved particularly effective for identifying spatially correlated compounds. Notably, compounds such as cyclotene, methylbutyric acid, and 1-(2-furanyl)ethanone seem to have higher intensities in toasted regions, consistent with previous reports based on barrel wood extracts. Additionally, previously unreported signals were observed in localized wood areas. Several compounds were tentatively identified using data-dependent acquisition (DDA) andMS/MS library matching.ConclusionAlthough this work at a preliminary stage, it demonstrates the feasibility of analyzing intact barrel staves by MALDI-MSI and establishes methodological strategies that will support comprehensive future studies of compound behavior in cognac barrels
Side-by-side first-price auctions with imperfect bidders
No full textWe model a procurement scenario in which two \textit{imperfect} bidders act simultaneously on behalf of a single buyer, a configuration common in display advertising and referred to as \textit{side-by-side bidding} but largely unexplored in theory. We prove that the iterated best response algorithm converges to an equilibrium under standard distributional assumptions and provide sufficient condition for uniqueness. Beyond establishing existence and convergence, our analysis provides a tractable numerical method for quantitative studies of side-by-side procurement
A complete list of He-pressure-broadening coefficient of CO2 lines from 100 K to 3000 K for planet and exoplanet opacity calculations
No full textInternational audienceHe pressure-broadening coefficients of CO 2 lines were predicted over a wide temperature range (100-3000 K) using requantized classical molecular dynamics simulations (rCMDS). This approach, based on the use of an ab initio intermolecular interaction potential, Newtonian equations of motion, and a requantized procedure, enables the calculation of the spectral density of He-broadened CO 2 spectra. The resulting spectra were fitted with the usual Voigt profile to deduce He-broadening coefficients. Requantization was calibrated to match the rCMDS-predicted broadenings coefficients to quantum scattering results at room temperature, available for thirteen lines, computed with the same potential. Comparisons between rCMDS and quantum calculations at 123 K and 760 K showed very good agreements. Excellent agreements with experimental data were also observed at 123 K, 160 K, 565 K, and 760 K. rCMDS calculations were then extended to several temperatures up to 3000 K, enabling prediction of broadening coefficients for rotational quantum numbers up to J = 240, where no prior theoretical or experimental data exist. The temperature dependence of the broadening coefficients was then determined using either a double power-law model when applicable or the usual single power law. The resulting dataset provides He-broadening coefficients of CO 2 lines for J up to 166 for any temperature between 100 K and 3000 K. These results represent the most comprehensive set of line-shape parameters for CO 2 perturbed by He, providing improved input for spectroscopic databases and for opacity modeling in planetary and exoplanetary atmospheres
Variational subspace methods and application to improving variational Monte Carlo dynamics
No full textWe present a formalism that allows for the direct manipulation and optimization of subspaces, circumventing the need to optimize individual states when using subspace methods. Using the determinant state mapping, we can naturally extend notions such as distance and energy to subspaces, as well as Monte Carlo estimators, recovering the excited states estimation method proposed by Pfau et al. As a practical application, we then introduce Bridge, a method that improves the performance of variational dynamics by extracting linear combinations of variational time-evolved states. We find that Bridge is both computationally inexpensive and capable of significantly mitigating the errors that arise from discretizing the dynamics, and can thus be systematically used as a post-processing tool for variational dynamics