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Search for Contact Interactions with Dimuons at the Atlas DetectorThompson, Emily 01 September 2011 (has links)
The Standard Model has been very successful over the last few decades in its agreement with experimental evidence; however there are some remaining puzzles in our understanding of the Universe which have yet to be solved. Even if the Higgs boson and Super Symmetry are discovered, questions still arise, such as why Nature is primarily made of matter when antimatter should have been produced in equal amounts at the beginning of the Universe, why the fundamental particles have the mass hierarchy that they do, what the nature of dark matter is, or whether or not quarks and leptons are themselves made of constituent parts, just to name a few. Theories Beyond the Standard Model attempt to tackle these questions, and also provide alternative explanations for electroweak symmetry breaking in case the Higgs mechanism in the Standard Model contradicts what is observed. The ATLAS detector was built to discover new physics from high-energy proton-proton collisions delivered by the Large Hadron Collider and to probe the electroweak scale with hard interactions at energies near ~1 TeV. While searching for new physics processes occurring at a much higher invariant mass than available at previous colliders, understanding the performance of the detector is crucial, especially during the first few months of running. This thesis presents a motivation for using dimuons to search for new physics in early ATLAS data, a measurement of the Z0/γ ->μμ cross section as a first test of Standard Model theoretical predictions at √s =7 TeVqqμμ, and finally a search for new physics via a four-fermion contact interaction in the dimuon channel (qqμμ) using the full 2010 data set.
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A Measurement of the W/Z Cross Section Ratio as a Function of Hadronic Activity with the ATLAS DetectorMeade, Andrew Robert 01 May 2013 (has links)
Hadronic collisions at the LHC at CERN probe particle interactions at the highest energy scale of any experiment to date. We present a research program measuring Rjet = &sigmaWBR(W&rarr&mu&nu) / (&sigmaZBR(Z&rarr&mu&mu)) as a function of a number of hadronic variables. The measurements are performed with the ATLAS detector at the LHC, using the 2011 data set, consisting of 4.64 fb-1 of pp collisions at a center of mass energy of 7 TeV. This measurement is a robust way to test the Standard Model and the modeling of perturbative QCD, and is sensitive to a wide variety of possible new physics in events with high jet ET, including some variations of Supersymmetry. By taking the ratio of W/Z production, a large number of systematic uncertainties cancel, including those associated with luminosity, jet energy scale and resolution, and many theoretical uncertainties.
The measurement of Rjet is performed as a function of the pT and rapidity of the 1st-4th leading jet, ST, HT, and a number of dijet variables, including invariant mass and angular separations. The measurements are compared with NLO theoretical predictions from Blackhat+Sherpa, as well as using leading order simulations from Alpgen and Sherpa. Over most of the kinematic phase-space, there is good agreement between the data and theoretical predictions. There is a significant deviation for exactly one selected jet above 30 GeV, where Blackhat+Sherpa over-estimates the ratio Rjet by 12%.
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Modelling of GaN Power SwitchesJogi, Sreeram January 2015 (has links)
No description available.
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Les climats et les étages végétaux de l'Atlas BlidéenAbdelkader, Halimi. 08 October 2024 (has links)
Dans ce mémoire, nous étudions, d'un point de vue géographique, le climat régional et ses relations avec la végétation dans l'Atlas Blidéen en Algérie, région montagneuse, où viennent converger les influences maritimes et continentales. Notre travail est subdivisé en trois partie*; observations météorologiques et types de temps, les bilans énergétiques et hydriques, les rapports climat-végétation. Dans la première partie, nous exposons et nous appliquons plusieurs méthodes pour homogénéiser les données d'observation. De plus, nous utilisons les types de temps pour comprendre les problèmes climatiques, en considérant pour ce faire des états globaux du milieu atmosphérique. La deuxième partie est consacrée au potentiel climatique de la région, formé des deux bilans énergétique et hydrique. Nous étudions d'abord en détail les températures et le rayonnement solaire, paramètres principaux du bilan énergétique. Nous nous consacrons ensuite à l'analyse des précipitations, premier élément du bilan d'eau et de l'évaporation, calculée suivant différentes méthodes, celle de Turc ayant finalement été retenue. Enfin, le bilan hydrique a été dressé pour les trois stations de Blida, Chrea et Medea, stations bien représentatives des différents secteurs régionaux et qui possèdent suffisamment de données. La troisième partie est une approche des rapports entre le climat et la végétation, rapports complexes et réciproques, dont nous retenons surtout l'influence générale du climat sur les étages de végétation. Nous exposons différents indices d'aridité simples ou composés et nous examinons leur importance non seulement sur le développement végétal mais aussi sur la croissance et la productivité potentielle agricole et forestière de la région. Enfin, notre analyse régionale nous a permis de délimiter six étages de végétation associés à autant de climats où se développent les principales associations végétales de l'Atlas: Pznetwn Halpensis, Cédretwn, Quercetum, Oteo-Leniicetwn.
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The case of Atlas Copco in Iran : An explorative study on market commitment and re-entry when facing economic sanctionsWalian, Martin January 2016 (has links)
No description available.
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Inbound Logistics Cost and CO<sub>2</sub> CalculationsKökler, Cihan January 2010 (has links)
<p>Business has globalized rapidly during the last decades. Distances between point of origin and point of consumption have increased as a result of globalization. Today’s increased distances mean that companies require faster logistic responses. Air transportation is preferred because it’s worldwide lead-time, of just 1-2 day, fulfill business expectations. However, transportation operation costs have risen dramatically and there are growing concerns about the high CO<sub>2</sub> emission levels associated with air transportation. These issues have recently become a point of focus for most globalized companies.</p><p>Currently, Atlas Copco Rock Drills AB, in Örebro is mostly using air transportation for their inbound logistics flow from North America <em>Shared Distribution Center </em>(SDC). In this thesis, sea transportation is surveyed to asses it’s suitability as a replacement in both economic and environmental terms. The formulated questions are:</p><p>(1) For which items can SDC use sea transportation instead of air transportation at the lowest cost and with the lowest risk?</p><p>(2) How much can SDC reduce their CO2 emission with the new setup? Does it comply with the ”environmental targets” of Atlas Copco Rock Drills AB?</p><p>(3) How would SDC make decisions about suitable transportation setups for additional items in the future?</p><p>When the transportation method is changed from air to sea more than one of the total logistics costs are affected. In reflection of the longer lead-times connected with sea transportation warehousing costs will increase. Therefore, when researching the ”lowest cost” we must consider the lowest total logistics cost. Extended lead-times also decrease the companies’ capability for flexibility; additionally, there will be heightened risk in connection with product life cycles. The possible environmental effects of sea transportation are considered carefully before an item’s transportation method change is suggested to the company. All calculations of CO<sub>2</sub> emissions have been done in accordance with <em>Nätverk </em><em><em></em></em><em><em>för Transporter och Miljö ’s (Network for Transporter and Environment) (NTM) formula </em></em>in order to reach a credible result. The findings are compared with the company’s environmental policy. An excel model has been developed to calculate results for extra items which may be added to the product range in the future.</p><p>As a result of the research analysis it has been shown possible to reduce total logistic cost up to, 33%, 3.247.000 SEK. By changing transportation mode, the CO<sub>2</sub> emission levels for transportation per item for these can even be reduced by up to 97%. Additionally, the excel model can be used internally to implement future changes.</p>
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The Geology of the Atlas Mine Area, Pima County, ArizonaAgenbroad, Larry D. January 1962 (has links)
The Atlas Mine is located on the northwest flank of the Silver Bell mountains; Silver Bell mining district, Pima County, Arizona. The deposit is high grade (?) sine-copper mineralization in an altered sedimentary sequence. Rocks in the area include Precambrian (?) alaskite; Permian (?) limestone, quartzite and siltstone; Tertiary (?) monzonite, quartz monzonite, quarts latite porphyry and dacite porphyry; and Quaternary alluvium. The limestone has been largely metamorphosed to a mass of tactite, siltstone has been locally metamorphosed to hornfels, and the quartzite has been silicified, locally shattered and altered. Mineralization is related to NE and E-W trending fault systems, and similarly trending intrusive dikes. Predominate ore minerals are sphalerite and chalcopyrite, associated with pyrite, specular hematite and “high temperature" silicates. Copper mineralization is related to the silicified sediments. Zinc mineralization is present in silicates but is more predominate in areas of recrystallized calcite and extensive garnetization, suggesting incomplete replacement of the original sediments by the silicates. Further exploration and development should be undertaken in areas of favorable structural control, and adjacent to favored intrusives.
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Lietuvos tvenkinių galimų panaudoti hidroenergetikai interaktyvus atlasas / Interactive map of Lithuania water reservoirs suitable for water-powerBalčiūnas, Tomas 16 June 2014 (has links)
Tiriamojo darbo objektas: Lietuvos tvenkiniai.
Tiriamojo darbo tikslas: nustatyti ir vizualizuoti potencialius tvenkinius (su pagrindinėmis techninėmis charakteristikomis), kuriuos būtų galima pritaikyti mažosios hidroenergetikos plėtojimui Lietuvoje, sudaryti Lietuvos tvenkinių interaktyvųjį atlasą.
Tiriamojo darbo uždaviniai:
1. Apžvelgti sudarytus ir veikiančius hidroenergetikos interaktyvius atlasus pasaulyje;
2. Palyginti ir išanalizuoti pasaulyje sukurtus atlasus;
3. Surinkti Lietuvos tvenkinių morfometrines, hidrologines ir kitas charakteristikas;
4. Sudaryti Lietuvoje esančių tvenkinių GIS duomenų bazę;
5. Išanalizuoti tvenkinių hidroenergetinius ir kitus parametrus;
6. Sukurtą tvenkinių atlasą palyginti su kitose šalyse egzistuojančiais atlasais.
Tiriamojo darbo metodika: Pagrindinis šaltinis, kuriuo buvo pasinaudota sudarant vandens jėgainių atstatymo vietų duomenų bazę, – Vandens išteklių instituto Microsoft Excel failu su istoriniais vandens tvenkinių duomenimis. Duomenys buvo papildyti ir atnaujinti pagal naujausią turimą informaciją. Atlasas sudarytas pasinaudojant ArcGIS 10.2 programine įranga ant GIS platformos. Sudarytas Vandens jėgainių atstatymo vietų interaktyvus žemėlapis buvo lyginamas su kitais, panašios tematikos, interaktyviais atlasais.
Tiriamojo darbo rezultatai:
1. Tyrimo metu buvo nustatytos 125 tvenkinių, kurių galia didesnė nei 10 kW vietos ir įvertinta kiek šių tvenkinių patenka į saugomas teritorijas. Daugiausia tvenkinių yra regioniniuose... [toliau žr. visą tekstą] / Object of the research: Lithuanian ponds
Aim of the research: to determine and visualize potential localities (with technical characteristics), which would be proper for development of small hydro energy in Lithuania, make an interactive water reservoirs atlas.
Objectives of the research:
1. To perform literature analyses, focusing on review of the existing hydropower interactive atlases;
2. To compare and analyze worlds existing atlases;
3. To collect the hydrological and other information of existing ponds;
4. To create GIS database of the existing ponds in Lithuania;
5. To analyze the hydro energetic parameters of the ponds;
6. To compare the created atlas with the other atlases in foreign countries.
Research methodology: the primary source, which have been used for reconstruction of water power sites database - the Microsoft Excel file from Water Resources Institute with historical data of water ponds. The data have been supplemented and updated according to the latest available information. Atlas was drawn up using the ArcGIS software 10.2 on a GIS platform. Reconstruction of water power sites composed of the interactive map was compared with other similar-themed, Interactive atlases.
Research results:
1. During the research it was found 125 ponds, with a power greater than 10 kW and it was rated how much of these ponds falls into the protected areas. Most ponds are in regional parks - 8 ponds and 4 ponds in Natūra 2000 territories.
2. The investigation estimated that... [to full text]
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Mise en oeuvre de l'étiquetage des jets issus de quarks beaux dans l'exprérience ATLAS au LHC / Commissioning of b-tagging in the ATLAS experiment at the LHCLapoire, Cécile 22 September 2010 (has links)
Le Modèle Standard de la physique des particules prédit l'existence du boson de Higgs,dont le canal de désintégration privilégié à basse masse est la production de paires de quarks beaux. L'identification des jets issus de tels quarks dans le détecteur ATLAS, situé sur l'anneau du LHC, tient donc un rôle majeur dans la physique des particules moderne.Dans ce document, un aperçu des méthodes d'étiquetage de ces jets b utilisées dans ATLAS ainsi que l'optimisation d'un algorithme en particulier, JetProb, sont présentés. La préparation à la mesure de l’efficacité de ces algorithmes dans les données est également développée. Enfin, après la prise de données à 900 GeV au centre de masse puis à l'énergie record de 7 TeV en 2009-2010, les premiers résultats concernant l'étude des traces chargées et la mise en place de l'étiquetage des jets b dans les données ont été obtenus et sont rassemblés ici. La comparaison avec la simulation montre un bon accord et les premiers candidats jets b et événements top observés sont étudiés. / The Standard Model of particle physics predicts the existence of the Higgs boson,which preferentially decays to b quark pairs at low mass. The identification of jets stemming from such quarks in the ATLAS detector, placed at the LHC, is thus one of the keysto modern particle physics.In this document, an overview of the b-tagging methods used in ATLAS as well as the optimization of a specific algorithm, JetProb, are presented. The preparation to the measurement of these algorithms efficiency in data is also developed. Finally, after the first datataking at 900 GeV and then at the record energy of 7 TeV in 2009-2010, the first results on charged track studies and b-tagging commissioning were obtained and are gathered together here. Comparison with simulation shows a good agreement and the first b-jet and top events candidates are studied.
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Étude de la production associée ZH/WH, H - ±gamma gamma» avec le détecteur ATLASBrelier, Bertrand January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.
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