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The Wineland parameter aims at detecting metrologically useful entangled states, called spin-squeezed states, from expectations and variances of total angular momenta. Efficient strategies for estimating this parameter in practice have yet to be determined. We here formulate the question of whether a state is spin-squeezed according to the Wineland parameter as an hypothesis test and assess the relevance of experimental outcomes by deriving upper and lower bounds on the p-value. By applying our statistical test to data obtained in multiple experiments, we are unable to reject the hypothesis that non-spin squeezed states were measured with a p-value of 5% or less in most cases. We also find an explicit non-spin squeezed state according to the Wineland parameter reproducing most of the observed results with a p-value exceeding 5%. Our results provide a rigorous method to establish robust statistical evidence of spin squeezing from the Wineland parameter in future experiments, accounting for finite-size effects.

The structural analysis of ultra-lightweight flexible shells and membranes may require the adoption of complex nonlinear strain-displacement relations. These may be approximated and simplified in some circumstances, e.g., in the case of moderately large displacements and rotations, in some others may be not. In this paper, the effectiveness of various geometrically nonlinear strain approximations such as the von Karman strains is investigated by making use of refined shell formulations based on the Carrera Unified Formulation (CUF). Furthermore, geometrical nonlinear equations are written in a total Lagrangian framework and solved with an opportune Newton-Raphson method. Test cases include the study of shells subjected to pinched loadings, combined flexure and compression, and post-buckling including snap-through problems. It is demonstrated that full geometrically nonlinear analysis accounting for full Green-Lagrange strains shall be performed whenever displacements are higher than the order of magnitude of the thickness and if compressive loads are applied.

This article investigates the large deflection and post-buckling of composite plates by employing the Carrera Unified Formulation (CUF). As a consequence, the geometrically nonlinear governing equations and the relevant incremental equations are derived in terms of fundamental nuclei, which are invariant of the theory approximation order. By using the Lagrange expansion functions across the laminate thickness and the classical finite element (FE) approximation, layer-wise (LW) refined plate models are implemented. The Newton-Raphson linearization scheme with the path-following method based on the arc-length constraint is employed to solve geometrically non-linear composite plate problems. In this study, different composite plates subjected to large deflections/rotations and post-buckling are analyzed, and the corresponding equilibrium curves are compared with the results in the available literature or the traditional FEM-based solutions. The effects of various parameters, such as stacking sequence, number of layers, loading conditions, and edge conditions are demonstrated. The accuracy and reliability of the proposed method for solving the composite plates' geometrically nonlinear problems are verified.

For the first time the scientific community in Latin America working at the forefront of research in high energy, cosmology and astroparticle physics (HECAP) have come together to discuss and provide scientific input towards the development of a regional strategy. The present document, the Latin American HECAP Physics Briefing Book, is the result of this ambitious bottom-up effort. This report contains the work performed by the Preparatory Group to synthesize the main contributions and discussions for each of the topical working groups. This briefing book discusses the relevant emerging projects developing in the region and considers potentially impactful future initiatives and participation of the Latin American HECAP community in international flagship projects to provide the essential input for the creation of a long-term HECAP strategy in the region., Comment: 89 pages

The LAGO (Latin American Giant Observatory) observatory is an experiment that spans over Latin America in a wide range of latitudes that gives different rigidity cut offs for the enter of cosmic rays in the atmosphere. The motivation of the Observatory is to study atmospheric radiation and space weather through the measurement of the secondary emission of low energy cosmic rays at ground level using Water Cherenkov Detectors (WCD). This work presents the contributions of the LAGO collaboration to the 2019 36th ICRC., Comment: International Cosmic Ray Conference 2019

The Latin American Giant Observatory (LAGO) is an extended cosmic ray observatory composed by a network of water-Cherenkov detectors spanning over different sites located at significantly different altitudes (from sea level up to more than $5000$\,m a.s.l.) and latitudes across Latin America, covering a huge range of geomagnetic rigidity cut-offs and atmospheric absorption/reaction levels. This detection network is designed to measure the temporal evolution of the radiation flux at ground level with extreme detail. The LAGO project is mainly oriented to perform basic research in three branches: high energy phenomena, space weather and atmospheric radiation at ground level. LAGO is built and operated by the LAGO Collaboration, a non-centralized collaborative union of more than 30 institutions from ten countries. These are the contributions of the LAGO Collaboration to the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands, Comment: 9 proceedings, the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands; in PoS(ICRC2015)