Test beam Characterizations of 3D Silicon Pixel detectors

3D silicon detectors are characterized by cylindrical electrodes perpendicular to the surface and penetrating into the bulk material in contrast to standard Si detectors with planar electrodes on its top and bottom. This geometry renders them particularly interesting to be used in environments where standard silicon detectors have limitations, such as for example the radiation environment expected in an LHC upgrade. For the first time, several 3D sensors were assembled as hybrid pixel detectors using the ATLAS-pixel front-end chip and readout electronics. Devices with different electrode configurations have been characterized in a 100 GeV pion beam at the CERN SPS. Here we report results on unirradiated devices with three 3D electrodes per 50 x 400 um2 pixel area. Full charge collection is obtained already with comparatively low bias voltages around 10 V. Spatial resolution with binary readout is obtained as expected from the cell dimensions. Efficiencies of 95.9% +- 0.1 % for tracks parallel to the electrodes and of 99.9% +- 0.1 % at 15 degrees are measured. The homogeneity of the efficiency over the pixel area and charge sharing are characterized.Comment: 5 pages, 7 figure

Recent results on GaAs detectors - 137

The present understanding of the charge collection in GaAs detectors with respect to the materials used and its processing are discussed. The radiation induced degradation of the charge collection efficiency and the leakage current of the detectors are summarised. The status of strip and pixel detectors for the ATLAS experiment are reported along with the latest results from GaAs X-ray detectors for non-high energy physics applications.Comment: 7 pages. 4 postscript figures + 1 postscript preprint logo + 1 LaTeX file + 1 style file. Also available at http://ppewww.ph.gla.ac.uk/preprints/97/05

Cartografia dos trabalhos de conclus?o de curso da Pedagogia da UFFS-Chapec? (SC)

This research exercise answers to the following problem: "What characteristics and contributions to teaching practice have marked the academic production within the framework of the Pedagogy Course Conclusion Work from Federal University of the Southern Frontier - Campus Chapec? (SC)?" Its purpose is to map the academic productions characterized as TCC. Methodologically, this is a qualitative / quantitative research, fulfilled with the documents already announced, covering the period from 2014 to 2017. The analysis and interpretation of the results was based on the contributions of Bardin (1977) and, more specifically, on the synthesis proposed by Trivi?os (1987), characterized by the processes of pre-analysis, categorical analysis and inferential analysis. The inventory was done from the available register in the institutional repository, systematizing it in a synoptic table, followed by the complete reading of the products, aiming, a posteriori, to identify which teaching learning were highlighted in the link with the profile of the pedagogue. Therefore, we listed 119 works registered as scientific articles considering that, in addition to the cartography, we proposed to find the contributions of the studies about teaching, we based it in the contributions of Arruda, Passos, Fregolente (2012), which referenced the FAD. It is worth mentioning that of the 119 (one hundred and nineteen) papers analyzed, 33 (thirty-three) of them present one or more focuses of teacher learning, thus, 27.73% of the mapped production is contemplated. In addition to this characteristic, the studies reveal directions, intentionalities, theoretical / methodological movements, in short a formative movement that deserves new studies, given the peculiarities of the course and institution.Este exerc?cio de pesquisa responde ao seguinte problema: ?Que caracter?sticas e contribui??es t?m marcado a produ??o acad?mica no ?mbito dos Trabalhos de Conclus?o de Curso de Pedagogia da Universidade Federal da Fronteira Sul - Campus Chapec? (SC)??. ? prop?sito deste, cartografar e apresentar as caracter?sticas e contribui??es das produ??es acad?micas caracterizadas como TCC. Metodologicamente, trata-se de uma pesquisa quali/quanti, realizada com os documentos j? anunciados, relativos ao per?odo de 2014 a 2017. A an?lise e interpreta??o dos resultados deram-se a partir das contribui??es de Bardin (1977) e, mais especificamente, a partir da sintetiza??o proposta por Trivi?os (1987), caracterizada como pr?an?lise, an?lise categorial e an?lise inferencial. Fez-se inicialmente o invent?rio a partir do registro dispon?vel no reposit?rio institucional, sistematizando-o em um quadro sin?ptico. Na sequ?ncia fez-se a leitura integral dos produtos, tendo em vista, identificar aprendizagens docentes que mereceram destaque em aten??o ao perfil do/a pedagogo/a. Por conseguinte, inventariamos 119 trabalhos registrados como artigos cient?ficos, cujas caracter?sticas traduzem movimentos reflexivos inerentes ? pr?ticas de ensino, pesquisa e extens?o. Mais especificamente, sendo curso de forma??o inicial damos centralidade aos Focos de Aprendizagem Docente, aportados nos estudos de Arruda, Passos, Fregolente (2012), os quais referenciaram os FAD. ? merit?rio destacar que dos 119 (cento e dezenove) trabalhos analisados, 33 (trinta e tr?s) deles apresentam um ou mais focos de aprendizagem docente, logo, contempla-se 27,73% da produ??o cartografada. Al?m desta caracter?stica, os estudos revelam rumos, intencionalidades, movimentos te?rico/metodol?gicos, enfim um movimento formativo que merece novos estudos, dadas ?s peculiaridades do curso e da institui??o

First fabrication of full 3D-detectors at SINTEF

International audienceA knowledge of the mechanical properties of bacterial biofilms is required to more fully understand the processes of biofilm formation such as initial adhesion or detachment. The main contribution of this article is to demonstrate the use of homogenization techniques to compute mechanical parameters of Pseudomonas aeruginosa PAO1 biofilms. For this purpose, homogenization techniques are used to analyze freeze substitution electron micrographs of the biofilm cross-sections. The concept of a representative volume element and the study about his representativeness allows us to determine the optimal size in order to analyze these biofilm images. Results demonstrate significant heterogeneities with respect to stiffness and these can be explained by varying cell density distribution throughout the bacterial biofilms. These stiffness variations lead to different mechanical properties along the height of the biofilm. Moreover, a numerical shear stress test shows the impact of these heterogeneities on the detachment process. Several modes of detachment are highlighted according to the local strain energy in the different parts of the biofilm. Knowing where, and how, a biofilm may detach will allow better prediction of accumulation and biomass detachment

R&D Paths of Pixel Detectors for Vertex Tracking and Radiation Imaging

This report reviews current trends in the R&D of semiconductor pixellated sensors for vertex tracking and radiation imaging. It identifies requirements of future HEP experiments at colliders, needed technological breakthroughs and highlights the relation to radiation detection and imaging applications in other fields of science.Comment: 17 pages, 2 figures, submitted to the European Strategy Preparatory Grou

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Optoelectronic analogue signal transfer for LHC detectors, 1991

We propose to study and develop opto-electronic analogue front-ends based on electro-optic intensity modulators. These devices translate the detector electrical analogue signals into optical signals which are then transferred via optical fibres to photodetector receivers at the remote readout. In comparison with conventional solutions based on copper cables, this technique offers the advantages of high speed, very low power dissipation and transmission losses, compactness and immunity to electromagnetic interference. The linearity and dynamic range that can be obtained are more than adequate for central tracking detectors, and the proposed devices have considerable radiation- hardness capabilities. The large bandwidth and short transit times offer possibilities for improved triggering schemes. The proposed R&D programme is aimed at producing multi-channel "demonstrator" units for evaluation both in laboratory and beam tests. This will allow the choice of the most effective technology. A detailed study will also be carried out on packaging and interconnection to large arrays of fibres, as well as on the optimization of the processes for the production of large quantities

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13