Browsing by Author "Oliveira, M."
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- Depth of maximum of air-shower profiles at the Pierre Auger Observatory. II. Composition implicationsPublication . Pierre Auger collaboration (485 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Oliveira, M.; Pimenta, M.; Santo, C.E.; Santos, E.; Sarmento, R.; Tome, B.Using the data taken at the Pierre Auger Observatory between December 2004 and December 2012, we have examined the implications of the distributions of depths of atmospheric shower maximum (Xmax), using a hybrid technique, for composition and hadronic interaction models. We do this by fitting the distributions with predictions from a variety of hadronic interaction models for variations in the composition of the primary cosmic rays and examining the quality of the fit. Regardless of what interaction model is assumed, we find that our data are not well described by a mix of protons and iron nuclei over most of the energy range. Acceptable fits can be obtained when intermediate masses are included, and when this is done consistent results for the proton and iron-nuclei contributions can be found using the available models. We observe a strong energy dependence of the resulting proton fractions, and find no support from any of the models for a significant contribution from iron nuclei. However, we also observe a significant disagreement between the models with respect to the relative contributions of the intermediate components.
- Highlights from the Pierre Auger ObservatoryPublication . Pierre Auger collaboration (496 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Oliveira, M.; Pimenta, M.; Santo, C.E.; Santos, E.; Tome, B.The Pierre Auger Observatory is the world’s largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km$^{2}$sr and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these, we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our X$_{max}$ data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass-sensitive parameters from the 100 % duty cycle surface detector (SD) data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of ultrahigh-energy cosmic ray (UHECR) sources are briefly discussed.
- The Portuguese Society of Rheumatology position paper on the use of biosimilars – 2017 updatePublication . Araújo, F. C.; Sepriano, A.; Teixeira, F.; Jesus, D.; Rocha, T. M.; Martins, P.; Tenazinha, C.; Cordeiro, A.; Mourão, A. F.; Silva, C.; Vaz, C.; Duarte, C.; Ponte, C.; Santos, F. P. dos; Canhão, H.; Santos, H.; Pimentão, J. B.; Silva, J. C. da; Polido-Pereira, J.; Silva, J. A. P. da; Miranda, L. C.; Oliveira, M.; Saavedra, M. J.; Gonçalves, P.; Falcão, S.; Capela, S.; Fonseca, J. E.