Reinterpretation of LHC results for new physics: Status and recommendations after run 2

We report on the status of efforts to improve the reinterpretation of searches and measurements at the LHC in terms of models for new physics, in the context of the LHC Reinterpretation Forum. We detail current experimental offerings in direct searches for new particles, measurements, technical implementations and Open Data, and provide a set of recommendations for further improving the presentation of LHC results in order to better enable reinterpretation in the future. We also provide a brief description of existing software reinterpretation frameworks and recent global analyses of new physics that make use of the current data

Enhanced transfer of organic matter to higher trophic levels caused by ocean acidification and its implications for export production : A mass balance approach

Ongoing acidification of the ocean through uptake of anthropogenic CO2 is known to affect marine biota and ecosystems with largely unknown consequences for marine food webs. Changes in food web structure have the potential to alter trophic transfer, partitioning, and biogeochemical cycling of elements in the ocean. Here we investigated the impact of realistic end-of-the-century CO2 concentrations on the development and partitioning of the carbon, nitrogen, phosphorus, and silica pools in a coastal pelagic ecosystem (Gullmar Fjord, Sweden). We covered the entire winter-to-summer plankton succession (100 days) in two sets of five pelagic mesocosms, with one set being CO2 enriched (similar to 760 mu atm pCO(2)) and the other one left at ambient CO2 concentrations. Elemental mass balances were calculated and we highlight important challenges and uncertainties we have faced in the closed mesocosm system. Our key observations under high CO2 were: (1) A significantly amplified transfer of carbon, nitrogen, and phosphorus from primary producers to higher trophic levels, during times of regenerated primary production. (2) A prolonged retention of all three elements in the pelagic food web that significantly reduced nitrogen and phosphorus sedimentation by about 11 and 9%, respectively. (3) A positive trend in carbon fixation (relative to nitrogen) that appeared in the particulate matter pool as well as the downward particle flux. This excess carbon counteracted a potential reduction in carbon sedimentation that could have been expected from patterns of nitrogen and phosphorus fluxes. Our findings highlight the potential for ocean acidification to alter partitioning and cycling of carbon and nutrients in the surface ocean but also show that impacts are temporarily variable and likely depending upon the structure of the plankton food web.Peer reviewe

Les Houches 2019 Physics at TeV Colliders: New Physics Working Group Report

This report presents the activities of the `New Physics' working group for the `Physics at TeV Colliders' workshop (Les Houches, France, 10--28 June, 2019). These activities include studies of direct searches for new physics, approaches to exploit published data to constrain new physics, as well as the development of tools to further facilitate these investigations. Benefits of machine learning for both the search for new physics and the interpretation of these searches are also presented

A SModelS interface for pyhf likelihoods

SModelS is an automatized tool enabling the fast interpretation of simplified model results from the LHC within any model of new physics respecting a Z_2 symmetry. We here present a new version of SModelS, which can use the full likelihoods now provided by ATLAS in the form of pyhf JSON files. This much improves the statistical evaluation and therefore also the limit setting on new physics scenarios

Evolución microestructural durante la transformación de la estructura pirocloro en perovskita en láminas de (Pb,La)TiO₃

A pyrochlore to perovskite transformation is known to occur during the rapid heating of sol-gel prepared La modified lead titanate ferroelectric thin films. This transformation is not inhibited by the Pb deficiency caused by PbO volatilisation at the initial stages of the thermal treatment. The microstructural evolution associated with this transformation occurring in the Pb deficient film has been studied by transmission electron microscopy. Plan view and cross section specimens were prepared from two films at different stages of the transformation. Experiments showed that the pyrochlore phase was homogenously distributed across the film thickness, with a very similar morphology to that of the ferroelectric phase. The combination of microdiffraction and microanalysis allowed identifying single grains that had not the perovskite structure, and were more Pb deficient than the film. Pore growth, grain growth, and growth of local texturing were observed along with the transformation.<br><br>Es conocido que se produce una transformación de estructura pirocloro a perovskita durante el calentamiento rápido de láminas delgadas ferroeléctricas de titanato de plomo modificadas con La, preparadas por sol-gel. La deficiencia de Pb causada por la volatilización de PbO en los primeros momentos del tratamiento térmico no inhibe la transformación. Se ha estudiado, por microscopía electrónica de transmisión, la evolución microestructural asociada a esta transformación, que ocurre en un medio que en promedio es deficiente en Pb. Con este fin, se prepararon muestras para microscopía, tanto del plano de la lámina como secciones transversales, a partir de dos láminas en las que la transformación se encontraba en estadios diferentes. Los experimentos pusieron de manifiesto que la fase con estructura pirocloro se encontraba homogéneamente distribuida a lo largo del espesor de la lámina, y que su morfología era muy similar a la de la fase ferroeléctrica. La combinación de las técnicas de microdifracción y microanálisis permitió identificar granos individuales que no tenían la estructura perovskita, y establecer que presentaban una deficiencia de Pb mayor que el promedio de la lámina. La microscopía electrónica de transmisión también puso de manifiesto fenómenos de crecimiento de poro, de grano, y del grado de texturación local durante la transformación

micrOMEGAs 6.0: N-component dark matter

International audiencemicrOMEGAs is a numerical code to compute dark matter (DM) observables in generic extensions of the Standard Model of particle physics. We present a new version of micrOMEGAs that includes a generalization of the Boltzmann equations governing the DM cosmic abundance evolution which can be solved to compute the relic density of N-component DM. The direct and indirect detection rates in such scenarios take into account the relative contribution of each component such that constraints on the combined signal of all DM components can be imposed. The co-scattering mechanism for DM production is also included, whereas the routines used to compute the relic density of feebly interacting particles have been improved in order to take into account the effect of thermal masses of t-channel particles. Finally, the tables for the DM self-annihilation - induced photon spectra have been extended down to DM masses of 110 MeV, and they now include annihilation channels into light mesons

micrOMEGAs 6.0: N-component dark matter

International audiencemicrOMEGAs is a numerical code to compute dark matter (DM) observables in generic extensions of the Standard Model of particle physics. We present a new version of micrOMEGAs that includes a generalization of the Boltzmann equations governing the DM cosmic abundance evolution which can be solved to compute the relic density of N-component DM. The direct and indirect detection rates in such scenarios take into account the relative contribution of each component such that constraints on the combined signal of all DM components can be imposed. The co-scattering mechanism for DM production is also included, whereas the routines used to compute the relic density of feebly interacting particles have been improved in order to take into account the effect of thermal masses of t-channel particles. Finally, the tables for the DM self-annihilation - induced photon spectra have been extended down to DM masses of 110 MeV, and they now include annihilation channels into light mesons

micrOMEGAs 6.0: N-component dark matter

International audiencemicrOMEGAs is a numerical code to compute dark matter (DM) observables in generic extensions of the Standard Model of particle physics. We present a new version of micrOMEGAs that includes a generalization of the Boltzmann equations governing the DM cosmic abundance evolution which can be solved to compute the relic density of N-component DM. The direct and indirect detection rates in such scenarios take into account the relative contribution of each component such that constraints on the combined signal of all DM components can be imposed. The co-scattering mechanism for DM production is also included, whereas the routines used to compute the relic density of feebly interacting particles have been improved in order to take into account the effect of thermal masses of t-channel particles. Finally, the tables for the DM self-annihilation - induced photon spectra have been extended down to DM masses of 110 MeV, and they now include annihilation channels into light mesons