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Terahertz Imaging of Early Stage Thermal Transformations in Oil Shale
No full textInternational audienceThe characterization of oil shales is essential for evaluating their quality and industrial potential. Existing techniques, such as X-ray tomography (XCT), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM–EDS), infrared (IR) and Raman spectroscopies, and nuclear magnetic resonance (NMR), provide valuable information. However, none of these methods offer millimetric/sub-millimetric-scale resolution with direct sensitivity to simultaneous changes in both water and organic matter within a bulk sample. To address this limitation, terahertz (THz) imaging has previously been applied to oil shales; however, no studies have explored its use under varying temperature conditions of the sample. This is particularly relevant, as heating the samples at low temperatures (<200 °C) can provide new insights into their structural and compositional evolution. Thus, in this work, we acquired THz images after sequential heating an oil shale sample at 40, 150, and 200 °C for 15 h each, in order to monitor its change during thermal evolution. The results revealed, for the first time, changes in the THz images arising from the evaporation of free water, the release of bound water from clays, and transformation of organic matter. These findings were validated and explained by complementary analyses, including X-ray diffraction (XRD), XCT, and Rock-Eval pyrolysis. Furthermore, a first effective absorption and refractive index model was proposed, which enabled the estimation of free and bound water evaporation
Three-loop pentagonal Wilson loop with Lagrangian insertion
No full textInternational audienceEmploying a cutting-edge bootstrap method, we analytically compute the three-loop pentagonal Wilson loop with Lagrangian insertion in planar super-Yang-Mills theory. This object is conjectured to coincide with the maximally transcendental part of the four-loop five-point all-plus amplitude in pure Yang-Mills theory. Our starting point is an ansatz that encodes the known leading singularities of this object, as well as the relevant function space. The latter has become available only recently, thanks to an analytic computation of all three-loop five-point planar massless Feynman integrals. We determine the coefficients in the ansatz by imposing physical constraints. This includes a near-collinear expansion, which so far has not been applied to this observable. Taken together, the constraints allow us to uniquely determine the symbol of the answer. We verify the symbol result by an independent integral reduction calculation
Shoulder rotators isokinetic profile according to instability and/or sport specificity: Implications for rehabilitation
No full textInternational audienceObjectives: To (i) describe the shoulder rotator muscle profiles across healthy, unstable, and athletic contexts, and (ii) to compare the usual Peak Torque (PT-method) and the Angular Range (AR-method).Design: Retrospective analysis of data collected cross-sectionally.Setting: Hospital. Each participant participated in isokinetic evaluations of the shoulder rotator muscles at 60°.s-1 (concentric/eccentric) for both shoulders.Participants: 239 participants of 24.7 (7.5) years INTERVENTION: None.Main outcome measures: We recorded the PT and AR mean torque by 10°, and we calculated the antagonist/agonist ratios. We used a two-way repeated measures ANOVA with a correction for multiplicity to compare laterality (i.e., side-to-side) and contexts (i.e., no-overhead sports healthy, no-overhead sports with unstable shoulder, overhead sports healthy and overhead sports with unstable shoulder RESULTS: Concentric PT of external rotators were significantly lower in no-overhead athletes with shoulder instability than healthy no-overhead athletes (p=0.007) and than healthy overhead athletes (p=0.029). The AR highlighted significant (p<0.05) lower concentric external and internal rotator muscles strength: i) in no-overhead athletes with shoulder instability than in healthy no-overhead athletes; ii) in healthy overhead athletes than in healthy no-overhead athletes; iii) in no-overhead athletes with shoulder instability than in healthy overhead athletes. No significant difference was observed in the eccentric modality or in the PT/AR ratios. Significant side-to-side differences (p<0.05) between dominant and non-dominant sides were reported by both PT and AR methods.Conclusion: Only the concentric muscle profiles differed across context groups. The AR allowed for a more precise detection of shoulder muscle adaptations by identifying unique muscle signatures in the moment-angle relationship. These 10° angular range measurements offer complementary information and enhance the clinical utility of isokinetic profiling compared to the traditional PT-method
In situ saxs investigation of the formation of mesostructured materials structured from polyion complex micelles
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Respective impacts of global warming, permafrost thaw and urban sprawl on debris-flow risk: Insights from the Dorfbach Torrent, Swiss Alps
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Critical metals behavior in amphibolite facies: metamorphic conditions and ore mineral compositions Sulitjelma and Bleikvassli Pb-Zn-Cu mines, Norwegian Caledonides.
No full textInternational audienceAs part of the Critical Metals in Orogen project (https://anr-cmio.gm.umontpellier.fr/), this study focuses on the presence and potential remobilization of critical metals, especially Indium, at the historic Sulitjelma Cu-Zn and Bleikvassli Zn-Pb-Cu mines in the Norwegian Caledonides. The style of mineralization is considered VMS and SEDEX, respectively, but both localities have suffered metamorphism and deformation during the formation of the Caledonian orogen. Ore and host rocks samples of the Sulitjelma and Bleikvassli mines were studied in order to understand the link between metamorphism, mobility, and critical metal concentrations within the mineralizations. To address this issue, several methods were used: macroscopic and microscopic analyses, thermodynamic modelling, EBSD, LA-ICP-MS, LIBS and EPMA in situ analysis. The host rocks are mostly metasediments composed of quartz, micas, garnet, staurolite, kyanite and rare sillimanite. Using pressure-temperature diagrams calculated for the host rock, we obtain for Bleikvassli, temperature conditions between 650 and 750 °C and pressure conditions between 6.5 and 11 kbar. For Sulitjelma, the metamorphic conditions are slightly lower, with temperatures between 550 and 700 °C and pressures between 5 and 12 kbar. These data suggest that the host rocks of the Bleikvassli and Sulitjelma mineralizations experienced amphibolite facies conditions associated with Barrovian metamorphism in a collisional context, in agreement with the available literature. Ore samples are dominated by pyrite–chalcopyrite–sphalerite and pyrrhotite–chalcopyrite–sphalerite assemblages, with the local presence of magnetite. EBSD results show that, in most of the samples, pyrrhotite, pyrite and chalcopyrite show a preferential orientation possibly indicating dynamic recrystallization whereas, sphalerite, appearing texturally late might have crystallized under static conditions. EMPA and LA-ICPMS in situ analytical results on the mineralizations indicate the presence of significant iron in sphalerite in both deposits with 4.4 wt% at Bleikvassli and 5.7 wt% ppm at Sulitjelma. In addition, cadmium, manganese, and indium are preferentially incorporated into sphalerite as well. In both deposits, there is a significant amount of indium in sphalerite, up to 55 ppm. Gallium and germanium concentrations in sphalerite are low. Indium and manganese are also present in chalcopyrite but at lower concentrations. By contrast, tin and silver are preferentially incorporated into chalcopyrite. Cobalt, nickel, and arsenic are enriched in pyrite
Measurements of the inclusive W and Z boson production cross sections and their ratios in proton-proton collisions at = 13.6 TeV
No full textInternational audienceMeasurements are presented of the W and Z boson production cross sections in proton-proton collisions at a center-of-mass energy of 13.6 TeV. Data collected in 2022 and corresponding to an integrated luminosity of 5.01 fb with one or two identified muons in the final state are analyzed. The results for the products of total inclusive cross sections and branching fractions for muonic decays of W and Z bosons are 11.93 0.08 (syst) 0.17 (lumi) (acc) nb for W boson production, 8.86 0.06 (syst) 0.12 (lumi) (acc) nb for W boson production, and 2.021 0.009 (syst) 0.028 (lumi) (acc) nb for the Z boson production in the dimuon mass range of 60-120 GeV, all with negligible statistical uncertainties. Furthermore, the corresponding fiducial cross sections, as well as cross section ratios for both fiducial and total phase space, are provided. The ratios include charge-separated results for W boson production (W and W) and the sum of the two contributions (W), each relative to the measured Z boson production cross section. Additionally, the ratio of the measured cross sections for W and W boson production is reported. All measurements are in agreement with theoretical predictions, calculated at next-to-next-to-leading order accuracy in quantum chromodynamics
Search for long-lived particles using displaced vertices of oppositely charged leptons in 140 fb of pp collisions at TeV with the ATLAS detector
No full textInternational audienceA search is presented for long-lived particles decaying into an oppositely charged lepton pair, , , or , that form a vertex within the inner tracking system of the ATLAS detector at the Large Hadron Collider, displaced from the primary proton-proton interaction region. The analysis uses the 140 fb of Run-2 data collected at TeV by the ATLAS experiment in 2015-2018. The results of the analysis are interpreted in the context of three benchmark models covering masses from 0.1 to 2.2 TeV and a range of mean proper lifetimes times the speed of light from 1 to 10000 mm. The first model is a generic boson pair-produced by a new heavy scalar, with the decaying into lepton pairs. The remaining two models are -parity violating supersymmetric models in which the lightest neutralino decays into (, ). The models differ by the mode of production of the , which can be produced via the decay of pairs of gluinos or of pairs of charginos and neutralinos (, , or ). Although each benchmark sample includes pair-produced LLPs, only a single vertex is required to be reconstructed. No dilepton displaced vertex candidate is observed and the results are presented as upper limits on the production cross-sections. This analysis sets leading limits on the production cross-sections for multiple models, including parameter space that has never been directly probed
Measurement of differential -channel single top (anti)quark production cross-sections at 13 TeV with the ATLAS detector
No full textInternational audienceThe production of single top quarks and top antiquarks via the -channel exchange of a virtual boson is measured in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider. The full Run 2 data sample recorded with the ATLAS detector in the years 2015-2018 is used, corresponding to an integrated luminosity of 140 fb. The absolute and normalised production cross-sections are measured differentially as a function of the transverse momentum and absolute rapidity of the top quark and top antiquark. In addition, the ratio of top quark to top antiquark production cross-sections is measured. The measured distributions are compared with next-to-leading-order quantum chromodynamics predictions obtained with different combinations of matrix-element generators, parton-shower programs and proton parton distribution functions, as well as to next-to-next-to-leading-order calculations. Overall, good agreement is observed between the measurements and the theoretical predictions. For most measured distributions, the sensitivity to differences between the predictions is limited by the systematic uncertainties in the measurement. The measured differential distributions are also interpreted in an effective field theory approach to constrain the Wilson-Coefficient associated with a four-quark operator. The interpretation accounts for the effect of the selection efficiency, which is altered significantly by non-zero contributions from
Dissipative Solutions to a Compressible Non-Newtonian Korteweg System with Density-Dependent Viscous Stress Tensor
No full textThe main objective of this paper is to prove that if capillarity effect is taken into account then there exist dissipative solutions to a system describing viscoplastic compressibleflows with density dependent viscosities in a periodic domain \T^d with . We calculate the relative entropy inequality and in consequence show existence of dissipative solutions and the weak-strong uniqueness for this system. Our result extends the recent result concerning the link between Euler--Korteweg and Navier--Stokes--Korteweg systemsfor Newtonian flows (when the viscosity depends on the density) [See D.~Bresch, M. Gisclon, I. Lacroix-Violet, {\it Arch. Rational Mech. Anal.} (2019)] to non-Newtonian flows