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CODE beyond FAIR: a roadmap for reusable research software
No full textInternational audienceFAIR principles are a set of guidelines aiming at simplifying the distribution of scientific data to enhance reuse and reproducibility. This article focuses on research software, which significantly differs from data in its living nature, and its relationship with free and open-source software. We provide a tiered roadmap to improve the state of research software, which takes into account the full range of stakeholders in the research software ecosystem: all scientific staff – regardless of prior software engineering training – but also institutions, funders, libraries and publishers
Deuteron-induced nuclear reactions to produce Lu: Extension of cross-sections data up to 33 MeV and impact on purity
No full textInternational audienceActivation cross-sections of lutetium and ytterbium radionuclides have been measured by deuteron-induced nuclear reaction on natYb(d,x) at the GIP ARRONAX (Saint-Herblain, France) cyclotron facility with a beam energy up to 33 MeV using the stacked-foil activation technique combined with high resolution γ-ray spectrometry. The measured experimental values enable the extension of the cross-section to higher energies. As a primary objective, we have focused on the cumulative measurement of the direct and indirect production routes of the therapeutic radioisotope 177gLu, via 176Yb(d,n) 177g,mLu and 176Yb(d,p) 177Yb →177gLu respectively. Post-irradiation gamma analysis, including a long gamma counting period, was performed to calculate the yield of the undesirable metastable isotopic impurity 177mLu. The results showed that it was found to be lower than our detection limit i.e. <0.0005% of 177gLu yield. Thick target yields for all detected radionuclides are also calculated in this paper. These measurements enabled the estimation of the production yield and isotopic purity of 177Lu obtained via deuteron-induced nuclear reactions for large production batches using highly enriched 176Yb2O3 samples (>99.5%). •Cross-section measurement of the theranostic radioisotope 177Lu induced by deuterons up to 33 MeV.•Metastable impurity 177mLu below the detection limit (<0.0005% of 177gLu yield).•Production yields and isotopic purities estimated from enriched 176Yb2O3 samples (>99.5%)
Instrumentation of JUNO 3-inch PMTs
No full textInternational audienceOver 25,600 3-inch photomultiplier tubes (PMTs) have been instrumented for the central detector of the Jiangmen Underground Neutrino Observatory. Each PMT is equipped with a high-voltage divider and a frontend cable with waterproof sealing. Groups of sixteen PMTs are connected to the underwater frontend readout electronics via specialized multi-channel waterproof connectors. This paper outlines the design and mass production processes for the high-voltage divider, the cable and connector, as well as the waterproof potting of the PMT bases. The results of the acceptance tests of all the integrated PMTs are also presented
Study of the interaction between baryons and light mesons via femtoscopy at the LHC
No full textInternational audienceMeson-baryon systems with strangeness content provide a unique laboratory for investigating the strong interaction and testing theoretical models of hadron structure and dynamics. In this work, the measured correlation functions for oppositely charged and pairs obtained in high-multiplicity pp collisions at TeV at the LHC are presented. For the first time, high-precision data on the interaction are delivered at small relative momenta. The scattering lengths, extracted via the Lednický-Lyuboshits expression of the pair wavefunction, indicate a repulsive and a shallow attractive strong interaction for the and systems, respectively. The and states are observed in the correlation function and their properties, mass and width, are determined. These measurements are in agreement with other available results. Such high-precision data can help refine the understanding of these resonant states, provide stronger constraints for chirally motivated potentials, and address the key challenge of describing the coupled-channel dynamics that may give rise to molecular configurations
Unveiling the sea: universality of the transverse momentum dependent quark distributions at small
No full textInternational audienceWithin the Colour Glass Condensate effective theory, we demonstrate that back-to-back dijet correlations in dilute-dense collisions involving a small- quark from the nuclear target can be factorised in terms of universal transverse momentum dependent distributions (TMDs) for the sea quarks. Two building blocks are needed to construct all these TMDs at the operator level: the sea quark TMD operator which appears in semi-inclusive Deep-Inelastic Scattering (SIDIS) or in the Drell-Yan process and the elastic -matrix for a quark-antiquark dipole. Compared to SIDIS, the saturation effects are stronger for dijet production in forward proton-nucleus collisions, due to additional scattering in the initial and final state, effectively resulting in a larger value for the nuclear saturation momentum
Exclusive four pion photoproduction in ultraperipheral Pb-Pb collisions at TeV
No full textInternational audienceThe intense photon fluxes from relativistic nuclei provide an opportunity to study photonuclear interactions in ultraperipheral collisions. The measurement of coherently photoproduced final states in ultraperipheral Pb-Pb collisions at TeV is presented for the first time. The cross section, d/d, times the branching ratio () is found to be mb in the rapidity interval . The invariant mass distribution is not well described with a single Breit-Wigner resonance. The production of two interfering resonances, and , provides a good description of the data. The values of the masses () and widths () of the resonances extracted from the fit are MeV/, MeV/, MeV/ and MeV/, respectively. The measured cross sections times the branching ratios are compared to recent theoretical predictions
Substitution for minimizing/maximizing a tropical linear (fractional) programming
No full textTropical polyhedra seem to play a central role in static analysis of softwares. These tropical geometrical objects play also a central role in parity games especially mean payoff games and energy games. And determining if an initial state of such game leads to win the game is known to be equivalent to solve a tropical linear optimization problem. This paper mainly focus on the tropical linear minimization problem using a special substitution method on the tropical cone obtained by homogenization of the initial tropical polyhedron. But due to a particular case which can occur in the minimization process based on substitution we have to switch on a maximization problem. Nevertheless, forward-backward substitution is known to be strongly polynomial. The special substitution developed in this paper inherits the strong polynomiality of the classical substitution for linear systems. This special substitution must not be confused with the exponential execution time of the tropical Fourier-Motzkin elimination. Tropical fractional minimization problem with linear objective functions is also solved by tropicalizing the Charnes-Cooper's transformation of a fractional linear program into a linear program developed in the usual linear algebra. Let us also remark that no particular assumption is made on the polyhedron of interest.Finally, the substitution method is illustrated on some examples borrowed from the litterature.</div
Impact of geophysical fields on Deep Learning-based Lagrangian drift simulations
No full textWe assess the influence of different Eulerian geophysical input fields on Lagrangian drift simulations using DriftNet, a learning-based method designed to simulate Lagrangian drift on the sea surface. Two experiments are conducted: a fully numerical experiment (Benchmark B1) and a real-world drifters-based experiment (Benchmark B2). Both experiments are performed in two regions with different ocean dynamics: North East Pacific and Gulf Stream regions. The performance of DrifNet is evaluated with three different metrics: separation distance between simulated and ground-truth trajectories, the normalized cumulative Lagrangian separation and the autocorrelation of Lagrangian velocities. In both regions, results from B1 show that combining assimilated sea surface currents (SSC) with fully observed sea surface height (SSH) leads to greatest improvement in trajectory simulation. This configuration reduces separation distance by over 50\% and significantly decreases normalized cumulative Lagrangian separation and metrics related to velocities autocorrelation functions compared to the baseline using SSC alone. On the other hand, the inclusion of sea surface temperature (SST) either alone or in combination with SSC generally degrades performance. In B2, using satellite-derived SSH, Ekman and winds velocities improves surface drifters trajectories simulation, particularly in the North East Pacific. While the satellite-derived SST in combination with reanalysis-based SSC configuration leads to better trajectories simulation in the Gulf Stream. Overall, we highlight the added value of combining multiple geophysical fields to improve Lagrangian drift simulation on both numerical and real-world experiments
Gluon splitting at small : a unified derivation for the JIMWLK, DGLAP and CSS equations
No full textInternational audienceWe revisit the calculation of the next-to-leading order (NLO) corrections to dijet production in electron-ion collisions at small . We focus on the back-to-back configuration where the relative transverse momentum of the measured jets is much larger than both their momentum imbalance and the target saturation momentum . In this regime, we present for the first time a complete calculation of the real NLO corrections at leading power in . Our result exhibits TMD factorisation, with the same hard factor as at tree-level and a NLO correction to the Weiszäcker-Williams (WW) gluon transverse momentum dependent (TMD) distribution which involves four Wilson-line operators. By studying different kinematical regimes for and for the radiated gluon, we recover all the quantum evolutions that were previously identified for this process at NLO: the B-JIMWLK high-energy evolution and the CSS evolution of the gluon WW TMD, and the DGLAP evolution of the gluon PDF. When both and the transverse momentum transferred by the target are large compared to , all the Wilson-line operators boil down to the unintegrated gluon distribution and our NLO result for the gluon TMD can be used to isolate the transverse-momentum dependent gluon splitting function
Measurement of the charged-particle-jet transverse-momentum fraction carried by prompt and non-prompt J/ mesons in pp collisions at TeV
No full textInternational audienceThe measurement of the transverse-momentum fraction () carried by prompt and non-prompt J/ in charged-particle jets in proton--proton collisions with a center-of-mass energy TeV is reported by the ALICE Collaboration at the CERN Large Hadron Collider. The measurement is based on a Transition Radiation Detector triggered data sample corresponding to an integrated luminosity of pb. Inclusive J/ mesons with transverse momentum () above 1 GeV/ are reconstructed at midrapidity through the electron--positron decay channel. The prompt and non-prompt J/ contributions are separated using the secondary vertices from beauty-hadron decays. Jets are reconstructed from J/-meson candidates and charged particles using the anti- algorithm with jet resolution parameter in the pseudorapidity range . The distribution of the charged-particle jet fraction carried by the prompt and non-prompt J/ mesons, , is measured in the range for the jet- range GeV/. The measured distributions for prompt and non-prompt J/ are compared to pQCD calculations and PYTHIA 8 simulations. Prompt and non-prompt J/ production within charged-particle jets are found to be qualitatively well reproduced by PYTHIA 8 for , however, as approaches one, the simulations overshoot the measured data, indicating an overestimation of the fraction of isolated J/. This observed tension between data and simulations in the highest bins reflects the challenge of simulating hadronization of low-momentum jets