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1
Lai, Chi-hsuan. "Neutrino electron plasma instability /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Heron, Heidi. "Techniques to measure the NC background in the SNO experiment." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244578.
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Astier, Pierre. "Recherche d'oscillations de neutrinos dans le canal neutrino-muon vers neutrino-electron aupres de l'accelerateur de brookhaven." Paris 7, 1987. http://www.theses.fr/1987PA077268.
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Ruan, Chong-yu. "From neutrinos to liquid clusters, structure investigations by electron scattering and related methods /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Caravaca, Rodríguez Javier. "Measurement of the electron-neutrino component of the T2K beam and search for electron-neutrino disappearance at the T2K Near Detector." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/283399.
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T2K es un experimento de oscilaciones de neutrinos de largo recorrido en el que por primera vez se
ha observado la aparición de neutrinos electrónicos en un haz de neutrinos muónicos. Así pues, el único ángulo de mezcla que quedaba por conocer, q13, es medido con gran precisión. el background principal de esta medida es la contaminación de neutrinos electrónicos producida en el haz junto con la componente de neutrinos muónicos. Ésta es una componente irreducible que ha de ser medida y controlada.
La componente intrínseca de neutrinos electrónicos es medida antes de las oscilaciones en el detector cercano de T2K confirmando la predicción de la simulación con un precisión del 10%. Se establece que el background de neutrinos electrónicos está bien reproducido y que la principal medida del experimento T2K es exacta.
Por otro lado, estudiar la componente de neutrinos electrónicos es interesante para investigar el comportamiento anómalo de algunos experimentos. Estudios en reactores nucleares y resultados en la calibración de experimentos de neutrinos solares con Galio han observado un déficit de neutrinos electrónicos a cortas distancias de la fuente. Este déficit no es compatible con oscilaciones de neutrinos estándar, pero puede ser conciliado en el marco de las oscilaciones, mediante la introducción de un cuarto neutrino con una masa del orden de 1eV². Este nuevo neutrino no sentiría ninguna fuerza del Modelo Estándar y por ello es comúnmente llamado neutrino estéril. Asumiendo que se mezcla con los neutrinos de tipo electrónico, explicaría la desaparición a cortas distancias de los mismos. El detector cercano de T2K se encuentra a una distancia de la fuente óptima para el estudio de oscilaciones de neutrinos estériles ligeros. El modelo más simple de neutrinos estériles con un sólo neutrino adicional es investigado, definiendo intervalos de confianza para los parámetros de oscilación y comparándolos con la literatura.The T2K experiment is a long baseline neutrino experiment that has observed for first time the appearance of electron-neutrinos in a muon-neutrino beam. Thanks to this analysis, the last unknown neutrino mixing angle q13 is measured with a good precision. The main background to this measurement is the contamination of electron-neutrinos produced in the neutrino beam together with the dominant muon-neutrino component. This is an irreducible component that needs to be measured and controlled. The prediction of this component at SuperKamiokande is based on the constrain of the neutrino flux and cross sections by a muon-neutrino selection at the T2K near detector ND280. To confirm this prediction, we measure the electron-neutrino event rates at ND280 before the oscillations occur, establishing that the electron-neutrino component is correctly reproduced by the simulation at the 10% level. In addition, studying the electron-neutrino component is interesting to investigate the abnormal behaviour of some neutrino experiments. The reactor neutrino experiments as well as the results from calibration with radioactive sources in solar neutrino experiment with gallium have observed a deficit of electron-neutrino at very short distances from the neutrino source. This depletion is not compatible with standard neutrino oscillation, but it can be explained by invoking a fourth neutrino with a mass of the order of 1eV². This neutrino does not feel any force of the Standard Model and hence is called sterile neutrino. Assuming that it mixes with the electron-neutrinos, it would be responsible of the short base-line electron-neutrino disappearance due to neutrino oscillation. The T2K near detector is located at a position short enough to study the light sterile neutrino oscillations. The neutrino model with an additional sterile neutrino apart from the three active species is tested and some constraints to the oscillation parameters are set and compared with the literature.
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Orrell, John Laurence. "A search for an electron antineutrino signal in the Sudbury Neutrino Observatory /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9794.
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Toner, Ruth Bushnell. "Measuring θ₁₃ via muon neutrino to electron neutrino oscillations in the MINOS experiment." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/265528.
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One of the primary goals in neutrino physics at the present moment is to make a measurement of the neutrino oscillation parameter B13 . This parameter, in addition to being unknown, could potentially allow for the introduction of CP violation into the lepton sector. The MINOS long-baseline neutrino oscillation experiment has the ability to make a measurement of this parameter, by looking for the oscillation of muon neutrinos to electron neutrinos between a Near and Far Detector over a distance of 735 km. This thesis discusses the development of an analysis framework to search for this oscillation mode. Two major improvements to pre-existing analysis techniques have been implemented by the author. First, a novel particle ID technique based on strip topology, known as the Library Event Matching (LEM) method, is optimized for use in MINOS. Second, a multiple bin likelihood method is developed to fit the data. These two improvements, when combined, increase MINOS' sensitivity to sin2(W13 ) by 27% over previous analyses. This thesis sees a small excess over background in the Far Detector. A Frequentist interpretation of the data rules out B13 = 0 at 91 %. A Bayesian interpretation of the data is also presented, placing the most stringent upper boundary on the oscillation parameter to date, at sin2 (2B13 ) < 0.09(0.015) for the Normal (Inverted) Hierarchy and 6cp = 0.
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Niederhausen, Hans. "Measurement of the High Energy Astrophysical Neutrino Flux Using Electron and Tau Neutrinos Observed in Four Years of IceCube Data." Thesis, State University of New York at Stony Brook, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10823307.
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The high-energy universe is known to be violent. Ultra High Energy Cosmic Rays (UHECRs) have been observed with kinetic energies exceeding 10 20 eV. Their origin, despite decades of observations, remains elusive. A unique probe of the sources and production mechanisms of these high energy cosmic rays can be neutrinos, since they are inevitably produced when high-energy protons interact. The IceCube Neutrino Observatory, located at the geographical South Pole in Antarctica, continuously monitors a total volume of 1 km 3 of clear Antarctic ice for neutrino interactions. For this purpose, a total of 5160 optical sensors (photomultiplier tubes) have been melted deep into the glacier at depths between 1450m and 2450m. In 2013 IceCube reported one of its biggest discoveries, the observation of highly energetic neutrinos that are consistent with a possible extra-galactic origin.
In this dissertation we use IceCube data (recorded from 2012 to 2015) to study the spectral properties of this astrophysical neutrino flux with focus on electron and tau neutrino flavors. We developed a new neutrino identification and muon background rejection method using state-of-the-art machine-learning techniques, more specifically multi-class gradient boosted decision trees. In addition to enlarging the number of detected neutrino events (>10x increase over previous works), we lowered the energy threshold to below 1 TeV and thereby greatly improved upon the control and treatment of systematic uncertainties. The sample contains ~400 astrophysical electron and tau neutrinos, which increases the significance of the original discovery to beyond 8 standard deviations. We find the astrophysical neutrino flux to be well described by a single power-law consistent with expectations from Fermi-type acceleration of high-energy particles at astrophysical sources and obtain leading constraints on its properties. We further studied the possibility of additional spectral complexity, which significantly increases measurement uncertainties. No evidence for such scenarios was found. Finally we searched for a contribution from atmospheric neutrinos related to heavy meson (charm) decay in Earth's atmosphere and derive a flux upper limit of 4.8 times the benchmark pQCD flux prediction at 90% confidence level, dominated by systematic uncertainties, especially related to photon transport in the glacial ice.
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Roncin, Romain. "From the measurement of the θ₁₃ mixing angle to the search for geo-neutrinos : studying electron antineutrinos with Double Chooz and Borexino." Paris 7, 2014. http://www.theses.fr/2014PA077141.
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Double Chooz est une expérience d'oscillation de neutrinos de réacteur qui a pour but de mesurer l'angle de mélange θ₁₃ grâce à deux détecteurs identiques situés à différentes distances des deux réacteurs de la centrale nucléaire de Chooz, dans les Ardennes françaises. Tandis que le détecteur proche commencera à prendre des données à l'automne 2014 afin de normaliser le flux des neutrinos émis par les réacteurs nucléaires, le détecteur lointain fonctionne depuis avril 2011 et permet d'observer la disparition des neutrinos à travers le phénomène d'oscillation de neutrinos. Cette thèse est également consacrée à l'expérience Borexino qui a été conçue afin d'observer les neutrinos solaires. Du fait d'un très faible bruit de fond ainsi que de son emplacement dans un pays sans réacteur nucléaire, l'Italie, Borexino est également sensible aux geo-neutrinos. Cette thèse présente à la fois les expériences Double Chooz et Borexino, de la description des détecteurs jusqu'aux principaux résultats, avec une attention particulière portée au bruit de fond et à sa rejection. Des études sur la directionalité des neutrinos avec ces deux expériences sont aussi détaillées. Pour Double Chooz, puisque les neutrinos proviennent des réacteurs nucléaires, la précision de la méthode d'analyse peut être évaluée. Cette thèse présente également pour la première fois la possibilité de retrouver la direction initiale des neutrinos quand les neutrons créés dans les réactions inverses de désintégration beta sont capturés sur l'hydrogène. Pour Borexino, l'information sur la directionalité des neutrinos pourrait faciliter la discrimination entre geo-neutrinos et neutrinos de réacteurs nucléairesDouble Chooz is a reactor neutrino oscillation experiment which aims at measuring the θ₁₃ mixing angle thanks to two identical detectors located at different distances from the two reactors of the Chooz nuclear power plant, in the French Ardennes. While the near detector will start taking data in fall 2014 to normalize the flux of the neutrinos emitted by the nuclear reactors, the far detector is running since April 2011 and allows to observe the neutrinos disappearance through the neutrino oscillation phenomenon. This thesis is also dedicated to the Borexino experiment which was designed to observe solar neutrinos. Due to its low background level as well as its position in a nuclear free country, Italy, Borexino is also sensitive to geo-neutrinos. This thesis presents both the Double Chooz and Borexino experiments, from the description of the detectors to the main results, with a special attention to the background and its rejection. Studies on the neutrino directionality with these two experiments are also detailed. In the case of Double Chooz, since the neutrinos are coming from the two nuclear reactors, the precision of the analysis method can be assessed. This thesis presents also for the first time the possibility to retrieve the initial direction of the neutrinos when the neutrons created in the inverse beta decay reactions are captured on hydrogen. In the case of Borexino, neutrino directionality information could facilitate the discrimination between geo-neutrinos and neutrinos from nuclear reactors
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Giganti, Claudio. "Particule Identification in the T2K TPCs and study of the electron neutrino component in the T2K neutrino beam." Paris 11, 2010. http://www.theses.fr/2010PA112334.
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Cette thèse est consacrée à la mesure de l'apparition du neutrino électronique avec l'expérience T2K. T2K est une expérience pour la mesure des oscillations de neutrinos installée au Japon. Le faisceau de neutrinos est produit par un accélérateur à JPARC et les neutrinos sont observés avant l'oscillation dans un détecteur proche, ND280, et après l'oscillation dans un détecteur lointain, SuperKamiokande. L'objectif de cette thèse est la mesure, avec le détecteur proche, de la composante intrinsèque de neutrinos électroniques dans le faisceau. Les TPC constituent le détecteur principal utilisé pour cette mesure. La première partie de la thèse décrit la méthode utilisée pour l'identification des particules (PID) : la méthode est basée sur la mesure de la moyenne tronquée de la charge déposée par les particules traversant le milieu gazeux. Les capacités de PID des TPC ont été testées avec des données en faisceau prises à TRIUMF avec un faisceau composé d'électrons, muons et pions ayant une impulsion jusqu'à 400 MeV. L'analyse de ces données confirme que la résolution sur l'énergie déposée dans la TPC est de l'ordre de 7%. Avec les premières données de l'expérience T2K une première mesure de la composante de neutrinos électroniques a été faite. Pour effectuer l'analyse, interactions de neutrinos dans ND280 ont été sélectionnées : cet échantillon est principalement composé par des interactions de neutrinos muoniques car les neutrinos électroniques sont de l'ordre de 1 % du nombre total de neutrinos dans le faisceau. La sélection avec le PID des neutrinos électroniques et muoniques, a permis une première mesure de la composante des neutrinos électroniques dans le faisceau de T2KThis thesis is devoted to the measurement of the electron neutrino appearance with the T2K experiment. T2K is a long baseline neutrino oscillation experiment that is taking data in Japan. The neutrino beam is produced by an accelerator in JPARC and neutrinos are observed in a Near Detector, ND280, before the oscillation and in the far detector, SuperKamiokande, after the oscillation. The aim of this thesis is the measurement of the intrinsic electron neutrino component of the beam with the Near Detector. The main detector used in this measurement is the ND280 TPC. The first part of the thesis describes the method developed for the particle identification in the TPCs: the PID method is based on the measurement of the truncated mean of the charge deposited by the particles crossing the gas. The PID capabilities of the TPCs have been tested analyzing the beam test data: these data have been taken at TRIUMF where we had a beam composed by electrons, muons and pions with momenta up to 400 MeV/c: the analysis of these data confirmed that the resolution on the deposited energy in the TPCs was of the order of 7%. When the first data of the T2K experiment were available, a first measurement of the electron neutrino component in the near detector has been done. To perform the analysis, a sample of neutrino interactions in ND280 was selected: this sample was mainly composed by muon neutrino interactions as the electron neutrino is expected to be 1 % of the total number of neutrinos in the beam. The selection of both, electron and muon neutrinos, allowed a first measurement of the electron neutrino component in the T2K beam
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Ruschmeier, Daniel. "Search for new physics in electron positron interactions with photons in the final state." Doctoral thesis, [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=958731357.
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Hourlier, Adrien. "Background studies for electron anti-neutrino oscillations measurement at the Double Chooz experiment." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC192/document.
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L’expérience Double Chooz étudie les anti-neutrinos électroniques provenant de réacteurs nucléaires pour mesurer le paramètre de mélange θ13 dans le phénomène d’oscillation des neutrinos. Deux détecteurs souterrains identiques sont placés à différentes distances des réacteurs de la centrale de Chooz dans les Ardennes. Le Détecteur Lointain est entré en service en avril 2011, et le Détecteur Proche en janvier 2015. Cette thèse présente une analyse des phases simple et double détecteurs de l’expérience. Les neutrinos sont détectés par désintégration β inverse dans Double Chooz, où un positron et un neutron sont émis, créant deux signaux coïncidents. Différentes analyses ont été menées sur des échantillons dans lesquels le neutron capture sur un atome de gadolinium ou d’hydrogène. Une analyse jointe des deux captures est également présentée. Les bruits de fond proviennent de la radioactivité ambiante et des muons atmosphériques (émetteurs (β-n), neutrons rapides et muons s’arrêtant et se désintégrant dans le détecteur). Cette thèse se focalise sur le développement de techniques pour réduire le bruit de fond lié aux muons se désintégrant dans le détecteur. Avec l’aide de collègues de l’APC et du MIT, un TPC à neutrons a été installé dans les deux laboratoires souterrains à Chooz. Cette chambre à projection temporelle, appelée DCTPC, remplie d’un mélange hélium/CF4 mesure le flux, le spectre en énergie, et la direction des neutrons rapides dans les deux laboratoires avec des blindages différents (respectivement 150 et 300 mètres équivalents d’eau pour le Laboratoire Proche et Lointain)Double Chooz is a reactor anti-neutrino experiment which measures the θ13 mixing parameter in the neutrino oscillation phenomenon thanks to two identical underground detectors located at different distances from the two reactors of the Chooz nuclear power plant in the French Ardennes. The Far Detector started data taking in April 2011 and the Near Detector began operations in January 2015. This thesis presents an analysis of both the single- and twodetector phases. Neutrinos interact in Double Chooz through inverse β decay on protons, where positron and a neutron are emitted, creating two coincident signals. Analyses were performed for each detector on independent samples using the neutron capture on Gadolinium or on Hydrogen. A combined analysis, using both neutron captures is also presented. Backgrounds to the neutrino sample originate from the ambient radioactivity and the abundance of atmospheric muons (cosmogenic (β-n) emitters, fast neutron showers, and muons stopping and decaying inside the detector). This thesis focuses on developing techniques for measuring and reducing the Stopping Muon background. With colleagues from APC and MIT, a 60 litre neutron TPC was installed in both underground laboratories at Chooz. This low pressure He/CF4-based time projection chamber, called DCTPC, measures the flux, energy spectrum and direction of fast neutrons in both locations, with different overburdens (150 and 300 meters water equivalent for the Near and Far Laboratories respectively)
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Fischer, Vincent. "Beta-decay emitted electronic antineutrinos as a tool for unsolved problems in neutrino oscillation physics." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066237/document.
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Le cadre global des oscillations de neutrinos est maintenant bien compris et nous quittons une ère d'exploration pour une ère de précision. L'expérience Double Chooz a pour but de mesurer l'angle de mélange theta13 par l'étude des oscillations des antineutrinos électroniques produits par les réacteurs de la centrale nucléaire de Chooz. Dans cette thèse, une sélection préliminaire des neutrinos détectés dans le détecteur proche est présentée. Les résultats les plus récents de Double Chooz, desquels sont extraits la mesure de theta13 la plus précise que l'expérience peut fournir à ce jour, seront également discutés. La géométrie de l'expérience, relativement simple, représente un avantage considérable afin d'effecteur des études de directionalité des neutrinos dont les résultats, obtenus en analysant les jeux de données les plus récents avec captures sur Gd et H, sont présentés. Ce concept de directionalité peut être appliqué à l'astronomie/astrophysique en offrant la possibilité de localiser des supernovas après détection de leurs neutrinos. Les résultats de simulations de directionalité effectuées avec différentes combinaisons de détecteurs seront présentées. Enfin, plusieurs anomalies pourraient s'expliquer par l'existence de nouveaux états, stériles, de neutrinos. Le but de l¿expérience CeSOX est de confirmer ou réfuter cette hypothèse en déployant une source radioactive à coté d'un grand détecteur comme KamLAND ou Borexino. Dans cette thèse seront présentés les résultats des simulations de signaux et de bruits de fond effectuées afin de valider le principe de l'expérience et de s'assurer de sa sensibilité à l'observation d'une oscillation vers un neutrino stérileThe framework of neutrino oscillations is quite well-understood and now requires precision rather than exploration. The Double Chooz experiment aims at measuring the theta13 mixing angle through the oscillations of electronic antineutrinos produced by the reactors of the Chooz nuclear power plant. The comparison of the interaction rates and spectral shapes in the two Double Chooz's detectors allows the observation of a disappearance and a spectral distortion, both driven by theta13. In this thesis, a preliminary neutrino selection with the near detector, whose data taking started in December 2014, has been performed. The most recent results of Double Chooz, providing the most precise measurement of the experiment, are presented as well.The simple layout of Double Chooz is a strong advantage to conduct directionality studies. Results of these studies using the most recent neutrino candidates with neutron captures on Gd and H are showed. Neutrino directionality can be applied to astronomy, with the localization of core-collapse supernovae. To this purpose, results of directionality measurements performed with combinations of large neutrino detectors over the globe are presented.Finally, recent anomalies observed in short baseline experiments provided hints of the hypothetical existence of additional sterile neutrino states. The goal of the CeLAND/CeSOX experiment is to test this hypothesis by deploying a radioactive source next to a large liquid scintillator detector such as KamLAND or Borexino. In this thesis, are presented results of signal and background simulations performed to validate the design and assess the sensitivity of such an experiment
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Dhen, Mikaël. "Muon to electron conversion, flavored leptogenesis and asymmetric dark matter in minimal extensions of the Standard Model." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/217745.
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Il est clair que le Modèle Standard des particules élémentaires n'est pas complet. Parmi tous les indices d'une physique au-delà du Modèle Standard, la masse des neutrinos, l'asymétrie matière-antimatière de notre Univers et la matière noire constituent les trois contextes généraux de cette thèse.Le fait que les neutrinos soient massifs constitue la plus claire évidence d'une physique au-delà du Modèle Standard. La masse des neutrinos peut trouver une explication notamment dans le cadre des modèles favoris dits "modèles Seesaw". Ces modèles, en plus de générer une petite masse pour les neutrinos, génèrent aussi des processus dans lesquels la saveur d'un lepton chargé est changée, comme la désintégration d'un muon en un électron et un photon, ou la conversion d'un muon en un électron au sein d'un atome sans émission de neutrino. Ces processus sont importants car les expériences futures devraient atteindre des sensibilités impressionnantes sur leurs taux, mais aussi parce que leur observation confirmerait l'existence d'une physique nouvelle et pourrait peut-être discriminé parmi les différents modèles. Il est donc important d'avoir une expression analytique fiable du taux de ces processus dans le cadre de ces modèles Seesaw favoris. Dans la première partie de cette thèse, nous calculons l'expression du taux de conversion d'un muon en un électron au sein d'un atome dans le cadre des modèles Seesaw de type 1, et analysons la phénoménologie s'y rapportant. Ces modèles Seesaw, en plus de générer une petite masse pour les neutrinos et des processus changeant la saveur leptonique, permettent aussi la création de l'asymétrie matière-antimatière dans l'Univers, à travers le mécanisme dit de "leptogenèse". Selon ce mécanisme, une asymétrie leptonique aurait d'abord été créée, avant d'être partiellement transférée en une asymétrie baryonique. Dans la seconde partie de cette thèse, nous calculons et analysons la leptogenèse dans le cadre des modèles Seesaw de type 2 avec, pour la première fois, la prise en compte des effets de saveurs.Finalement, la troisième et dernière partie de cette thèse se concentre sur la possibilité de générer non seulement la matière baryonique à partir d'une asymétrie, mais aussi la matière noire. A cette fin, nous considérons le modèle dit "doublet inerte'', car il contient une interaction qui pourrait à priori générer de la matière noire à partir d'une asymétrie. Nous adressons dès lors la question suivante et y répondons: est-il possible de générer toute la matière noire à partir d'une asymétrie de matière noire dans le contexte du modèle doublet inerte ?Option Physique du Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Martins, Mauro Sebastião. "História das partículas: de elétrons aos quarks." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/13384.
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Previous issue date: 2008-05-13This Work, a thesis in history of subatomic particles, is an historic and epistemological development study of the theoretical and experimental subatomic particles and antiparticles from the early Dirac s quantum theory of the electron, published in a year of 1928, until the publications of the theories of the quarks in a decade of the sixths, the Gell Mann theory of quarks include. That research studies was made in primaries and secondary bibliographies, didactic manuals, articles of scientific journals and scientific magazines, history and philosophy of science books and history of particles books. This studies show that in the delimitated period of study, the paradigmatic theories and experiments appear in the period call of common science, in suite the scientific period is the crisis, so, have a concurrency theories and experimental models period, finally appear a paradigmatic theory and experimental model, like the Khun historical analyses. The paradigmatic particles theories and experimental models, appear a manner of broke up whit of old scientific know, like understood of Bachelard analysis. In the daily period the candidate of paradigmatic theory of particles is the supercordas theory. However, ours studies are conclusive that it have a periodic cycle, into theirs, appear the paradigmatic theoretical and experimental models and had surpassed in the suite period by others paradigmatic theoretical and experimental models, and other periodic cycle occur when of paradigmatic theories and experimental models appear, and so on
Este trabalho, uma tese em história das partículas subatômicas, é um estudo da evolução histórica e epistemológica das teorias e experimentos em partículas e antipartículas, desde o advento da teoria quântica do elétron de Dirac, no ano de 1928, até as publicações das teorias sobre os quarks da década de sessenta, incluindo, nestas, a teoria dos quarks de Gell Mann. Os estudos foram embasados nos levantamentos de bibliografias primárias e secundárias: manuais didáticos, artigos de revistas e jornais científicos, obras em história e filosofia da ciência e em história das partículas. Ele demonstra que o período delimitado para o estudo revela que as teorias e experimentos paradigmáticos surgem após um período de ciência normal, seguido de crise e concorrência entre as teorias e modelos experimentais, como compreendido pela análise histórica de Thomas Khun. As teorias e experimentos paradigmáticos, em partículas, surgem de rupturas com o velho conhecimento estabelecido, como entendido pela análise epistemológica de Bachelard, do desenvolvimento do conhecimento científico. No período atual a candidata à teoria paradigmática em partículas, segundo a manifestação da comunidade científica dos pesquisadores em física de partículas, é a teoria das supercordas. Entretanto, os estudos são conclusivos, quanto à existência de ciclos periódicos, nos quais, as teorias e modelos paradigmáticos aparecem e são superados por outras teorias e modelos paradigmáticos emergentes
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Hollnagel, Annika [Verfasser], and Caren [Akademischer Betreuer] Hagner. "Energy reconstruction of electron neutrino events and muon neutrino-to-electron neutrino appearance search in the OPERA detector / Annika Hollnagel ; Betreuer: Caren Hagner." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1164158724/34.
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Tenti, Matteo <1982>. "Electron identification and reconstruction with the OPERA ECC bricks and search for muon neutrino to electron neutrino oscillations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4294/.
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The procedure for event location in OPERA ECC has been optimazed for penetrating particles while is less efficient for electrons.
For this reason new procedure has been defined in order to recover event with an electromagnetic shower in its final state not located with the standard one. The new procedure
include the standard procedure during which several electromagnetic shower hint has been defined by means of the available data. In case the event is not located, the presence of an electromagnetic shower hint trigger
a dedicated procedure. The old and new location procedure has been then simulated in order to obtain the standard location efficiency and the possible gain due to the new one for the events with electromagnetic shower. Finally a Data-MC comparison has been performed for the 2008 and 2009 runs for what concern the NC in order to validate the Monte Carlo. Then the expected electron neutrino interactions for the 2008 and 2009 runs has been evaluated and
compared with the available data.
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Holin, A. M. "Electron neutrino appearance in the MINOS experiment." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/20223/.
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The MINOS experiment is a long-baseline neutrino oscillation experiment which sends a high intensity muon neutrino beam through two functionally identical detectors, a Near detector at the Fermi National Accelerator Laboratory in Illinois, 1km from the beam source, and a Far detector, 734km away, in the Soudan Mine in Minnesota. MINOS may be able to measure the neutrino mixing angle parameter sin{^2}2\theta{_1_3} for the first time. Detector granularity, however, makes it very hard to distinguish any \nu{_e} appearance signal events characteristic of a non-zero value of \theta{_1_3} from background neutral current (NC) and short-track \nu{_\mu} charged current (CC) events. Also, uncertainties in the hadronic shower modeling in the kinematic region characteristic of this analysis are relatively large. A new data-driven background decomposition method designed to address those issues is developed and its results presented. By removing the long muon tracks from \nu{_\mu}-CC events, the Muon Removed Charge Current (MRCC) method creates independent pseudo-NC samples that can be used to correct the MINOS Monte Carlo to agree with the high-statistics Near detector data and to decompose the latter into components so as to predict the expected Far detector background. The MRCC method also provides an important cross-check in the Far detector to test the background in the signal selected region. MINOS finds a 1.0-1.5 \sigma\nu{_e}-CC excess above background in the Far detector data, depending on method used, for a total exposure of 3.14x10{^20} protons-on-target. Interpreting this excess as signal, MINOS can set limits on sin{^2}2\theta{_1_3}. Using the MRCC method, MINOS sets a limit of sin{^2}2\theta{_1_3} < 0:265 at the 90% confidence limit for a CP-violating phase \delta = 0.
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Liu, Ji. "Electron Neutrino Appearance in the Nova Experiment." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1499449859.
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The NuMI off-Axis $\nu_e$ Appearance (NO$\nu$A) experiment is a long baseline, off-axis neutrino oscillation experiment. It is designed to search for oscillations of $\nu_\mu$ to $\nu_e$ by comparing measurements of the NuMI beam composition in two detectors. These two detectors are functionally identical, nearly fully-active liquid-scintillator tracking calorimeters and located at two points along the beam line to observe the neutrinos. The Near Detector (ND), situated \unit[1]{km} away from the proton target at Fermilab, measures neutrinos prior to oscillation. Then the Far Detector (FD), located 810 km away at Ash River, Minnesota, measures the neutrinos after they have traveled and potentially oscillated. The neutrino beam is generated at Fermi National Accelerator Laboratory in Batavia, Illinois by the Neutrinos at the Main Injector (NuMI) facility. By observing the $\nu_\mu\to\nu_e$ oscillation, NO$\nu$A is capable of measuring the neutrino mass hierarchy, CP violation and the octant of mixing angle $\theta_{23}$. This thesis presents the first measurement of $\nu_e$ appearance in the NO$\nu$A detectors with $3.52\times10^{20}$ protons-on-target (POT) data accumulated from February 2014 till May 2015. In this analysis the primary $\nu_e$ CC particle selection LID observes 6 $\nu_e$ like events in the far detector with a background prediction of $0.99\pm0.11$ (syst.), which corresponds to a $3.3\sigma$ excess over the no-oscillation hypothesis. This results disfavors $0.1\pi < \delta_{cp} < 0.5\pi$ in the inverted mass hierarchy at $90\%$ C.L with the reactor constrain on $\theta_{13}$.
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Mohanmurthy, Prajwal. "Topics on electron,neutrino and axion scattering." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/103161.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Physics, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 61-64).
Under the broad topic of scattering, in this thesis we particularly investigate Lorentz invariance using Compton Scattering at the Compton Polarimeter located in Hall-C at Thomas Jefferson National Accelerator Facility. The Mississippi State Axion Search, an axion search experiment which uses light shining through a wall technique is described in detail, including its instrumentation, initial tests and future impact. Furthermore, a novel method of detection of solar anti-neutrinos based on coherent neutrino scattering is described. Additionally, on the instrumentation side, development of a multi-purpose beam instrument based on synchrotron light to measure the electron beam polarization, beam profile and intensity at the future Electron Ion Collider is presented.
by Prajwal Mohanmurthy.
S.M.
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Yang, Tingjun. "A study of muon neutrino to electron neutrino oscillations in the MINOS experiment /." May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Deniz, Muhammed. "Measurement Of Sm Electro-weak Parameters In Reactor Antineutrino-electron Scattering In Texono Experiment." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608386/index.pdf.
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In this thesis a search for electron type neutrino-electron scattering cross-section and Weinberg
Angle measurements were performed at KS Nuclear Power Station with 200 kg CsI(Tl) scintillating crystal detector located at a distance of 28 m from the 2.9 GW reactor core giving total flux of 6:52X10^12 cm^-2s^-1 in average at
the experimental site. New analysis techniques and background suppression methods were developed. In the region of 3-8 MeV a measurement of SM cross section of (1:235+-0.577) XR_SM and Weinberg Angle of 0:264 +-0.075
which is quite consistent with the SM value of 0.23120(15)were obtained. These are the best results with wold wide level sensitivities at untested low energy region by using reactor anti-neutrinos.
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Bay, Muhammet Fatih. "Study Of Electron Identification In The Opera Detector." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609649/index.pdf.
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The OPERA experiment is designed to perform first direct observation
of $nu_{tau}$ appearance in an almost pure $nu_{mu}$ beam. The
OPERA detector is a hybrid set-up which combines a lead/emulsion
target with various electronic detectors. It is located in Gran
Sasso Laboratory (LNGS), 730 km away from CERN where neutrino beam
is produced. A good electron identification in the ECC brick would
also allow OPERA to search for $nu_{mu}rightarrownu_{e}$
oscillations. We have studied electron identification in the
Emulsion Cloud Chamber (ECC) brick which was exposed to CERN SPS H4
electron beam. Emulsion scanning was performed in LNGS scanning
laboratory. FEDRA framework was used for the data analysis. In
total, we have found 30 electron showers in the brick. The
characteristics of each shower have been studied. The background
base-track contamination in the shower was estimated as $20pm 4$.
This is mainly due to shower overlap of electrons and passing
through cosmic rays.
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Jillings, Christopher James. "The electron scattering reaction in the Sudbury Neutrino Observatory." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0006/NQ42947.pdf.
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Hoenes, Michael. "Potential of harvesting solar neutrinos to power electric cars." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264284.
Full textAbstract:
Imminent penalties for excess emissions force the automotive industry to radically rethink how to power vehicles. Novel concepts are needed to facilitate these changes, which might be found by scouting patents of emerging and established companies. During their patent search, Daimler AG has come across a patent of the startup Neutrino Energy GmbH, which reveals a device designed to harvest solar neutrinos for electricity generation purposes. From here the question arises: Is it possible to harvest solar neutrinos to power electric consumers, such as cars? To answer this question, this study analyzes the solar neutrino flux on Earth’s surface and the state-of-the-art solar neutrino technology (including solar neutrino detectors used in research and the solar neutrino converter proposed by Neutrino Energy GmbH). The energy inherent to the solar neutrino flux is computed based on the solar neutrino spectrum found in literature. Solar neutrino detectors are analyzed on their ability to harvest solar neutrinos by consulting literature and by estimating their power output. In case of the graphene based converter by Neutrino Energy GmbH, the threshold energies of neutrino-graphene interactions are compared to the energies of incoming neutrinos to estimate an upper limit for the power output. Results from the analysis of the solar neutrino flux show that the energy inherent to solar neutrinos is too low to power an electric vehicle, even if it could be fully exploited. In fact, only a tiny fraction of the solar neutrino energy flux can be converted into electricity as neutrinos barely interact with matter. The analysis of the state-of-the-art solar neutrino research shows that detectors with a weight of several tonnes are constructed to capture signals from solar neutrinos. Still, the power output of such detectors is several orders of magnitude lower than the demand of an electric vehicle. Analyzing the concept developed by Neutrino Energy GmbH shows that only a small part of the solar neutrino flux can be harvested, insufficient to generate a significant amount of electricity. Hence, the conclusion is drawn, that solar neutrino conversion technology is no suitable candidate to enable sustainable mobility.
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Li, Gang. "Electron-neutrino angular correlation measurement in the decay of lithium-8." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110473.
Full textAbstract:
The Standard Model has been very successful in describing existing experimental data in nuclear and particle physics, but it still depends on numerous experiments for the determination of several important properties. For example, the assumption that only Vector(V) and Axial-Vector(A) interactions are present out of five possible types of weak interactions: V, A, Scalar(S), Pseudoscalar(P) and Tensor(T) is based on experimental results. The ion trap is an promising way for precise measurement of the beta-neutrinoangular correlation parameter "a" in beta decay. The unperturbed observation of the recoiled nucleus and electron allows reconstruction of the full decay kinematics. The goal of the BPT (Beta-decay Paul Trap) project is to measure "a" in the decay of 8Li. A deviation from the predicted value a =―1/3 would be an indication of a tensor contribution. 8Li was produced at the Argonne National Laboratory and about 20,000 events were recorded. By measuring the energy shift of the alpha particles in the 8Li decay, "a" is determined to be a =―0.329±0.009. This measurement is consistent with the Standard Model prediction. Upgrade of the system for a higher precision measurement is discussed.Le Modèle Standard a connu un très grand succès pour décrire les mesures expérimentales autant en physique nucléaire qu'en physique des particules. Cependant, plusieurs expériences tentent toujours de vérifier certaines de ses hypothèses de base. Par exemple, c'est grace à des résultats expérimentaux, que l'on sait que seules les interactions de type Vecteur (V) et Axial-Vecteur (A) sont présentes dans le Modèle Standard, bien qu'il y a théoriquement trois autres types d'interactions faibles possibles : Scalaire (S), Pseudoscalaire (P) et Tenseur (T). Les pièges d'ions sont une avenue prometteuse pour mesurer précisément le paramètre de correlation angulaire bêta-neutrino, "a", des désintégrations bêta. L'observation du noyau de recul et de l'électron en l'absence de perturbations externes permet la reconstruction de la cinématique complète des désintégrations. Le but du projet BPT (Beta-decay Paul Trap) est de mesurer "a" à partir de désintégrations d'ions 8Li. Toute déviation des mesures par rapport à la valeur théorique a = ―1/3 serait une indication d'une contribution d'interactions de type Tenseur. Des ions 8Li ont été produits au Argonne National Laboratory, où prês de 20 000 événements ont été enregistrés. En mesurant le décalage énergétique des particules alpha originant de désintégrations 8Li, une valeur de a =―0.329±0.009 a été déterminée pour le paramètre de corrélation angulaire. Cette valeur est en accord avec la prédiction du Modèle Standard. Une amélioration du dispositif pour permettre des mesures de plus grande précision est discutée.
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Alizadeh, Ramin. "A new upper limit on the electron anti-neutrino rest-mass." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236237.
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Lasorak, Pierre. "A search for neutrino-induced single photons and measurement of oscillation analysis systematic errors with electron and anti-electron neutrino selections, using the off-axis near detector of the Tokai to Kamioka experiment." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/39755.
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This thesis describes the search for neutrino-production of single photons using the off-axis near detector at 280 metres (ND280) of the T2K experiment. A photon selection is used to perform the searches using the first Fine Grained Detector (FGD1) of the ND280. The thesis also highlights the importance of systematic uncertainties in the analysis, since the selection is background dominated. After careful characterisation of the systematic uncertainties and estimation of the efficiency, it is concluded that, with the selected 39 data events and the expected background of 45 events, the limit for neutrino-induced single photons, at T2K energies, is 0:0903 x 10-38cm2/nucleon. This result can be compared with the expected limit of 0:1068 x 10-38cm2/nucleon. Using ND280's neutrino energy distribution (peaked at 600 MeV), NEUT predicts a flux-averaged cross section of 0:000239 x 10-38cm2/nucleon. A fit to the muon and electron (anti-) neutrinos selections in the ND280 was performed. The aim of this analysis is to use a data-driven method to constrain the electron (anti-) neutrinos background events at SK, the far detector and electron neutrino cross section parameters for oscillation analyses. These are fundamental inputs in the context of the searches for Charge-Parity (CP) violation in the neutrino sector. After a fit to the nominal Monte Carlo was realised, the electron neutrino and anti-neutrino cross section normalisation uncertainties are found to be 7.6% and 19.3%, repectively. Although these numbers are much higher than the assumed 3% uncertainty of all the CP violation searches performed at T2K up to now, the difference in the δCP log-likelihood is found to be acceptable as the one sigma contours are not very different and the exclusion of the δCP = 0 is roughly the same.
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Murphy, Matthew Douglas. "Inclusive and exclusive electron scattering data analysis from Jefferson Lab experiment E12-14-012." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/101964.
Full textAbstract:
Since the first observations of neutrino oscillation, neutrino experiments have come a long way toward precise measurements of the neutrino oscillation parameters, but some obstacles still remain. The next generation of oscillation experiments, including the Deep Underground Neutrino Experiment (DUNE), will be using the Liquid Argon Time Projection Chambers (LArTPCs) with natural argon as the neutrino target material. A precise model of the neutrino cross section on argon does not exist, which is a source of significant uncertainty in such experiments. The E12-14-012 experiment at Jefferson Lab seeks to help remedy this via electron scattering measurements on argon and titanium targets. The experiment collected both inclusive (e,e') and exclusive (e,e'p) data at a wide range of kinematics with the intent to measure the electron-nucleus cross section and thus derive a spectral function for argon that can be used with neutrino experiments. The use of titanium in this experiment stems from the equivalent shell structure that its protons share with the neutrons in argon, which will be crucial in oscillation experiments but cannot be measured directly in electron scattering. This thesis collects several papers which present results from the E12-14-012 experiment. These results include the inclusive (e,e') cross sections for carbon, titanium, argon, and aluminum at a beam energy of 2.22 GeV and a scattering angle of 15.54 deg with uncertainty of less than 5%. Also included are the first results of the exclusive (e,e'p) cross section on argon and titanium.Doctor of Philosophy
Since the first observations of neutrino oscillation, neutrino experiments have come a long way toward precise measurements of the neutrino oscillation parameters, but some of the properties of neutrinos still remain uncertain. The next generation of neutrino oscillation experiments, including the Deep Underground Neutrino Experiment (DUNE), will be using the Liquid Argon Time Projection Chambers (LArTPCs) with natural argon as the neutrino target material. A precise model of the neutrino cross section on argon does not exist, which will reduce the opportunity for DUNE to measure the neutrino properties with high precision. The E12-14-012 experiment at Jefferson Lab seeks to help remedy this via electron scattering measurements on argon and titanium targets. The experiment collected both inclusive (e,e') and exclusive (e,e'p) data.The goal of this experiment is measure the electron-nucleus interactions and provide a nuclear model for electron and neutrino interactions. This Ph.D. thesis collects several papers which present the results from the Jefferson lab E12-14-012 experiment.
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Rayyan, Saifuddin Ramadan. "Phenomenological Consequences of Heavy Right Handed Neutrinos." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27879.
Full textAbstract:
The discovery of neutrino mixing provides the possibility of a non vanishing CP violating phase in the neutrino mixing matrix. CP violation in the leptonic sector can be large enough to explain the matter-antimatter asymmetry in the universe. An indirect probe of CP violation is the experimental measurement of Electric Dipole Moment (EDM). CP violation has been discovered in the quark sector,but it contributes to lepton EDM at the 3-loop level.
Neutrino masses can be generated in the standard model via the see-saw mechanism where heavy right-handed neutrinos mix with the weak-basis states. The Majorana nature of the seesaw type neutrinos generates new 2-loop diagrams that lead to a non-vanishing lepton EDM. Only estimates of the resulting EDM have been done in the literature. A full calculation of the 2-loop diagrams and the exact result is presented.Ph. D.
31
Cox-Mobrand, Gary A. "Data integrity and electronic calibrations for the neutral current detector phase measurement of the 8B solar neutrino flux at the Sudbury Neutrino Observatory /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/9647.
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Sabetfakhri, Ali. "A search for electron and neutrino compositeness in ep collisions at HERA." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ53842.pdf.
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Voigt, Bernhard. "Sensitivity of the IceCube detector for ultra-high energy electron-neutrino events." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2008. http://dx.doi.org/10.18452/15850.
Full textAbstract:
Zur Zeit wird das IceCube Neutrino-Teleskop am Südpol im Eis der Antarktis installiert, die Hälfte des Detektors ist bereits im Betrieb. Bei Fertigstellung im Jahr 2011 wird mehr als 1 km^3 Eis mit Photovervielfachern instrumentiert sein. IceCube bietet damit eine einzigartige Möglichkeit, die Quellen der kosmischen Strahlung mit Hilfe hochenergetischer Neutrinos zu finden. Im Rahmen dieser Arbeit wurde die Sensitivität des kompletten Icecube Detektors für den Nachweis eines diffusen Flusses von Elektronneutrinos bestimmt. Ziel war es, die Eigenschaften des Detektors für Energien oberhalb von einem PeV zu bestimmen. Besonderes Augenmerk wurde dabei auf die Simulation von elektromagnetischen Kaskaden gelegt, die in Neutrino-Nukleon-Wechselwirkungen auftreten. Da existierende Parametrisierungen die Unterdrückung der Wechselwirkungsquerschnitte durch den LPM-Effekt nicht beinhalten, wurde eine Simulation des Energieverlustes von elektromagnetischen Kaskaden für Energien oberhalb von 1 PeV entwickelt, die entsprechend modifizierte Wirkungsquerschnitte verwendet. Die Analyse, die in dieser Arbeit vorgestellt wird, nutzt die komplette Information des durch einen Photovervielfacher aufgezeichneten Ladungsverlaufes aus, die mit der Datennahme des IceCube Detektors zur Verfügung steht. Es werden neue Methoden entwickelt, um zwischen atmosphärischen Myonen-Hintergrund- und Signalereignissen von Kaskaden aus Neutrino-Nukleon-Wechselwirkungen zu unterscheiden. Die erreichbare Sensitivität innerhalb einer Laufzeit von einem Jahr ist 1.5*10^-8 E^-2 GeV/(cm^2 sr s) in einem Energiebereich von 16 TeV bis 13 PeV für den Nachweis von Elektronneutrinos eines diffusen Flusses. Eine Verbesserung von mindestens einer Größenordnung wird erwartet, wenn alle Neutrinofamilien in die Analyse einbezogen werden. Damit sollte eine Sensitivität erreicht werden, die auf dem gleichen Niveau einer diffusen Myonenanalyse liegt.IceCube is a neutrino telescope currently under construction in the glacial ice at South Pole. At the moment half of the detector is installed, when completed it will instrument 1 km^3 of ice providing a unique experimental setup to detect high energy neutrinos from astrophysical sources. In this work the sensitivity of the complete IceCube detector for a diffuse electron-neutrino flux is analyzed, with a focus on energies above 1 PeV. Emphasis is put on the correct simulation of the energy deposit of electromagnetic cascades from charged-current electron-neutrino interactions. Since existing parameterizations lack the description of suppression effects at high energies, a simulation of the energy deposit of electromagnetic cascades with energies above 1 PeV is developed, including cross sections which account for the LPM suppression of bremsstrahlung and pair creation. An attempt is made to reconstruct the direction of these elongated showers. The analysis presented here makes use of the full charge waveform recorded with the data acquisition system of the IceCube detector. It introduces new methods to discriminate efficiently between the background of atmospheric muons, including muon bundles, and cascade signal events from electron-neutrino interactions. Within one year of operation of the complete detector a sensitivity of 1.5*10^-8 E^-2 GeV/(cm^2 sr s) is reached, which is valid for a diffuse electron-neutrino flux in the energy range from 16 TeV to 13 PeV. Including all neutrino flavors in this analysis, an improvement of at least one order of magnitude is expected, reaching the anticipated performance of a diffuse muon analysis.
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UROS, CORRALES VICTOR. "Experience nomad de recherche d'oscillations neutrino muon a neutrino tau : etude de la radiation de photons reels durs dans la diffusion par courant charge neutrino electron-nucleon." Paris 6, 1995. http://www.theses.fr/1995PA066223.
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Nomad est une experience de recherche d'oscillation entre le neutrino muon et le neutrino tau aupres d'un accelerateur (sps au cern). Pour l'identification des interactions par courant charge du neutrino tau on utilise des criteres purement cinematiques. Parmi les canaux de desintegration du tau le canal en electron est l'un des plus sensibles. Dans cette these on etudie en detail l'une des sources de bruit de fond potentielles dans ce canal, a savoir, la diffusion par courant charge des neutrinos electron avec emission d'un photon dur. Notre travail nous a amenes, d'abord, a calculer la section efficace radiative, et ensuite, a developper un generateur d'evenements radiatifs. Cela nous a permis d'etudier la cinematique de ces evenements, de montrer leur specificite par rapport au bremsstrahlung de l'electron dans la cible, et, finalement, d'estimer le bruit de fond recherche. Les resultats de notre analyse montrent que cette nouvelle source de bruit de fond est peu importante par rapport aux sources deja etudiees (elle contribue dans une proportion de l'ordre de 10% du fond total). Nous avons remarque que le bruit de fond du a la production directe d'electrons par la diffusion par courant charge des neutrino electron est produit a un transfert d'impulsion inferieur a 4 gev#2. Notre generateur, qui utilise le modele des partrons, n'est pas l'outil adequat pour simuler cette physique a des valeurs si faibles du transfert. Un generateur specifique se revele necessaire et est a l'etude dans le cadre de la collaboration
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Bilmis, Selcuk. "Study On Non Standard Interaction Of Neutrino And Unparticle Physics With Neutrino-electron Scattering Data At Low Energy In Texono Experiment." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612495/index.pdf.
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Neutrino-electron scatterings are purely leptonic processes with robust Standard Model (SM)
predictions. Their measurements can therefore provide constraints to physics beyond SM.
The &nue &minus
e&minus
data taken at the Kuo-Sheng Reactor Neutrino Laboratory were used to probe two sceneria: Non-Standard Neutrino Interactions (NSI) and Unparticle Physics. New constraints were placed to the NSI parameters (&epsilon
eL , &epsilon
eR ), (&epsilon
eL , &epsilon
eR ) and (&epsilon
eL , &epsilon
eR ) , as well as to the coupling constants for scalar (&lambda
0 ) and vector (&lambda
1 ) unparticles to the neutrinos and electrons.
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Niner, Evan. "Observation of electron neutrino appearance in the NuMI beam with the NOvA experiment." Thesis, Indiana University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3722542.
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NOvA is a long-baseline neutrino oscillation experiment that uses two functionally identical detectors separated by 810 kilometers at locations 14 milliradians off-axis from the NuMI muon neutrino beam at Fermilab. At these locations the beam energy peaks at 2 GeV. This baseline is the longest in the world for an accelerator-based neutrino oscillation experiment, which enhances the sensitivity to the neutrino mass ordering. The experiment studies oscillations of the muon neutrino and anti-neutrino beam that is produced. Both detectors completed commissioning in the summer of 2014 and continue to collect data. One of the primary physics goals of the experiment is the measurement of electron neutrino appearance in the muon neutrino beam which yields measurements of the oscillation parameters $\sin
{2}2\theta_{13}$, $\delta$, and the neutrino mass ordering within the standard model of neutrino oscillations. This thesis presents the analysis of data collected between February 2014 and May 2015, corresponding to $3.52\times 10
{20}$ protons-on-target. In this first analysis NOvA recorded 6 electron neutrino candidates which is a $3.3\sigma$ observation of electron neutrino appearance. The T2K experiment performs the same measurement on a baseline of 295 kilometers and has a $1~\sigma$ preference for the normal mass ordering over the inverted ordering over the phase space of the CP violating parameter $\delta$, which is also weakly seen in the NOvA result. By the summer of 2016 NOvA will triple its statistics due to increased beam power and a completed detector. If electron neutrinos continue to be observed at the current rate NOvA willl be able to establish a mass ordering preference at a similar confidence level to T2K.
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Gu, Linjie. "JLab E12-14-012 (e,e'p) cross section measurements for Ar and Ti." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/104091.
Full textAbstract:
In recent years, many high precision experiments were carried aiming to improve the accuracy on the measurements of the neutrino oscillation parameters. One of the main source of uncertainty for neutrino oscillation experiments is due to the lack of a comprehensive theoretical description of neutrino-nucleus interactions. The US Deep Underground Neutrino Oscillation Experiments (DUNE) will deploy a series of detectors using Liquid Argon Time Projection Chambers (LArTPCs). A fully consistent parameter-free theoretical neutrino-nucleus scattering model on argon does not exist. The first step towards constructing a nuclear model will be to determine the energy and momentum distribution of protons and neutrons inside the argon nucleus. The JLab E12-14-012 experiment performed at Jefferson Laboratory in Newport News, Virginia, ran in 2017 and will provide such measurements in Argon and Titanium using electron scattering (e,e'p). The data collected by the experiment covers a wide range of energy transfers and also includes several other targets like aluminum and carbon. This Ph.D. thesis will present details of the JLab E12-14-012 experiment, together with first data analysis results of the exclusive (e,e'p) data on Argon and Titanium.Doctor of Philosophy
Neutrino, a tiny, nearly massless particle was discovered about one hundred years ago. Neutrinos are everywhere around us. If you put your hands under the sunlight, each second, there will be about one billion neutrinos pass through them. As the second most abundant particle in the universe, it is extremely important to study neutrinos as they affect many fundamental aspects of our lives. For examples, neutrinos could help us study the nucleons' structure, and how the matter evolved from one particle to many. Since neutrinos are produced in nuclear fusion processes from the sun and stars, we could also understand the sun and universe better by studying the property of neutrinos. Neutrinos have three flavors, and they could change flavors through neutrino oscillation. Measuring the neutrino oscillation parameters is one of the priority tasks for the physics society. Lots of experiments were carried aiming to enhance the understanding of neutrinos and improve the neutrino oscillation measurements accuracy. The most exciting and famous one is the Deep Underground Neutrino Experiment (DUNE) that will be carried in Fermilab. DUNE is an accelerator based experiment that will use Argon as the neutrino target to study the neutrino oscillation. In order to improve the measurement accuracy of the oscillation parameters for the DUNE, a well defined theoretical model for neutrino interaction on Argon is needed. Thus, the JLab E12-14-012 experiment was performed in Hall A at Jefferson Lab in Newport, News, VA to help people get ready for this through electron scattering. The primary goal of this experiment is to measure the electron-nucleus interaction through (e,e$^\prime$p) reactions and further develop a electron-nucleus model to be used in the future neutrino experiments. This thesis will present an overview of the experimental setup and results from the data analysis.
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Costa, José Abritta. "Eletrônica de front-end do experimento Neutrinos-Angra." Universidade Federal de Juiz de Fora (UFJF), 2014. https://repositorio.ufjf.br/jspui/handle/ufjf/4165.
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O experimento Neutrinos Angra visa desenvolver um detector compacto e novas técnicas para medir o fluxo de antineutrinos das reações nucleares que ocorrem no interior dos reatores de usinas nucleares, permitindo o monitoramento da sua dissipação de energia instantânea e revelando a composição físsil de combustível nuclear. Este trabalho apresenta o desenvolvimento da eletrônica de front-end do Detector Neutrinos Angra. Esta eletrônica deve realizar o condicionamento dos sinais provenientes de tubos fotomultiplicados, visando fornecer ao sistema de aquisição de dados um pulso que facilite a identificação do fluxo de antineutrinos que passa pelo detector. Neste trabalho, as especificações do front-end foram definidas com base nos requisitos do experimento, que são: faixa linear de operação de 0 a 50 fótons; capacidade para identificar um fóton; duração do pulso menor do que alguns µs; largura de banda do pulso menor do que 60 MHz; excursão máxima na saída de até 2 V. Para isto, uma topologia do circuito de front-end foi proposta, sendo composta por quatro subsistemas: circuito de alimentação; circuito de condicionamento do sinal; circuito de controle de offset na saída e de limiar de tensão; e circuito discriminador. Oito módulos foram produzidos para equipar o detector. Neste trabalho, três módulos foram avaliados. Os testes mostraram que o desempenho dos três módulos atenderam as especificações, apresentando uma calibração média de 7,4±0,6 V/V , tempo de subida de 26±1 ns, tempo de descida de 81 ±2,5 ns, largura a meia altura de 74±1 ns, não-linearidade menor do que 2,2% para toda a faixa dinâmica de entrada e a saturação iniciando em aproximadamente 1,4 V.
The Neutrinos Angra Experiment aims to develop a compact detector and new techniques to measure the antineutrinos flow of nuclear reactions occurring inside the nuclear power plant reactors, allowing monitoring of its instant energy dissipation and revealing the composition of fissile nuclear fuel. This study presents the development of the Front-end electronics of the Neutrinos Angra detector. The electronics should perform the conditioning of the signals from photomultiplier tubes, aiming to provide a fast pulse for the data acquisition system whitch could facilitate the identification of the antineutrinos flow through the detector. In this work, the specifications of the front-end were defined based on the experiment requirements, which are: linear operating range 0-50 photons; ability to identify a single photon; the pulse duration less than a few µs; bandwidth of the pulse smaller than 60 MHz; maximum range in the output up to 2 V. For this, a topology of the front-end circuit has been proposed, consisting of four subsystems: power circuit; signal conditioning circuit; offset control circuit and discriminator circuit. Eight modules were produced to equip the detector. In this study three modules were evaluated. Tests showed that the performance of three modules met the specifications, with an average calibration of 7.4±0.6 V/V , rise time of 26 ±1 ns, falltime of 81 ±2.5 ns, width at half height of 74±1 ns, linearity better than 2.2% and saturation starting around 1.4 V.
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Dai, Hongxia. "Measurement of the (e,e') cross section for 12C, 48Ti, 27Al and 40Ar." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/94050.
Full textAbstract:
In the upcoming deep underground neutrino experiment (DUNE), Liquid Argon Time Projection Chambers (LArTPCs) will be used as the detector technology, and argon will be used as the nuclear target. In order to reduce the systematic uncertainties on the extracted oscillation parameters, a more precise description of the argon nuclear structure is needed. Electron scattering has been one of the most powerful methods of studying the nuclear structure of a target. Therefore we performed an electron scattering experiment E12-14- 012 in Hall A at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). In the E12-14-012 experiment, we collected data for the inclusive (e,e′) and exclusive (e,e′p) processes for a variety of targets (argon, titanium, aluminum, carbon) at a wide range of kinematics. This thesis presents the measurements of the double differential cross sections for carbon, titanium, aluminum and argon at beam energy E = 2.222 GeV and scattering angle θ = 15.541◦Doctor of Philosophy
In the upcoming deep underground neutrino experiment (DUNE), Liquid Argon Time Projection Chambers (LArTPCs) will be used as the detector technology, and argon will be used as the nuclear target. In order to reduce the systematic uncertainties on the extracted oscillation parameters, a more precise description of the argon nuclear structure is needed. Electron scattering has been one of the most powerful methods of studying the nuclear structure of a target. Therefore we performed an electron scattering experiment E12-14- 012 in Hall A at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). In the E12-14-012 experiment, we collected data for the inclusive (e,e′ ) and exclusive (e,e′p) processes for a variety of targets (argon, titanium, aluminum, carbon) at a wide range of kinematics. This thesis presents the measurements of the double differential cross sections for carbon, titanium, aluminum and argon at beam energy E = 2.222 GeV and scattering angle θ = 15.541◦ .
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Whitehead, Leigh. "A measurement of the electron neutrino component of the T2K beam using the near detector." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/51675/.
Full textAbstract:
T2K is a long baseline neutrino oscillation experiment located in Japan, with a 295km baseline and peak neutrino energy of 0:6 GeV. It is the first off-axis neutrino experiment where the beam is directed approximately 2.5° away from the detectors in order to produce a narrow-band neutrino beam. The experiment was designed to measure the mixing angle θ13 by measuring the neutrino oscillation process vμ -> ve. This measurement relies on the detection of electrons at the far detector from oscillations, and so it is vital to understand the size of the intrinsic ve component of the beam. A measurement of the intrinsic ve component of the T2K beam was performed using the ND280. An analysis that used all of the data taken by the ND280 from February 2010 until March 2011, a total of 1.09 x 10 20 POT, measured 67.7 +- 12.9(stat) +- 5.2(syst) CC ve interactions. The number of events corresponds to a ratio between data and simulation of 0.983+-0.191(stat)+-0.076(syst) and provides strong evidence that the neutrino flux is well simulated. The simulation from the intrinsic ve measurement was then combined with an analysis of vμ interactions in the ND280 to constrain the neutrino flux uncertainties. An idealised study that considered only statistical and flux systematic uncertainties concluded that the intrinsic ve analysis improved the constraint on the flux uncertainties compared to considering only the ND280 vμ analyses, with the effect most prominent at neutrino energies greater than 1 GeV.
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Cicenas, Blake John. "Optimization of a fiducial volume for a 10 kiloton water Cerenkov detector for geo-neutrinos." Thesis, Wichita State University, 2013. http://hdl.handle.net/10057/10629.
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A fiducial volume is crucial in particle physics when trying to choose the shape and size of a particle detector. The fiducial volume is defined as the volume at which a specified number of energy events are to be accepted. Fiducial volumes are impacted by aspects such as size and geometry. The fiducial volume in this study is optimized to contain the highest number of events generated from geo-neutrinos for the Hawaii Anti-Neutrino Observatory Project (HANOHANO). Geo-neutrinos are defined as anti-neutrinos coming from the earth either through radioactive decay or from a hypothetical nuclear reactor (geo-reactor). Five different volume types were tested and each type was able to contain at least 98% of anti-neutrino events. This study will demonstrate that an elliptical-cylinder is the best fiducial volume geometry for the HANOHANO project.Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Geology
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Cerna, Cédric. "MUNU : étude de la diffusion neutrino-électron." Université Joseph Fourier (Grenoble), 2000. http://www.theses.fr/2000GRE10197.
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Munu est une experience dediee a l'etude de la diffusion neutrino-electron de laquelle peut etre deduite une limite sur le moment magnetique du neutrino. L'experience est situee aupres d'un reacteur de la centrale nucleaire de bugey (france). La detection est basee sur une chambre a projection temporelle (tpc) immergee dans 10 tonnes de scintillateur liquide agissant comme blindage actif anti-compton. La signature d'une diffusion neutrino-electron est un unique electron de recul completement contenu dans la tpc. L'interet physique d'une telle recherche est decrit dans une premiere partie, ainsi que la conception generale du detecteur. Les principes de la calibration de l'anti-compton ainsi que leurs resultats sont exposes. Ils incluent le controle en ligne de la reponse des photomultiplicateurs ainsi que le suivi de la transparence du scintillateur. Les performances attendues et observees de la tpc fonctionnant avec du cf4 sont passees en revue. La discrimination des evenements est faite en utilisant l'emission de lumiere et la collection des charges ainsi que la topologie des traces. Une estimation de l'activite des materiaux basee sur des evenements alpha et beta est donnee. Ces evenements sont aussi ulitises pour mesurer certains parametres de la tpc comme la carte de gain de l'anode, la longueur de derive ou la longueur d'absorbtion des electrons. Il est montre dans quelle mesure les electrons simples partiellements contenus peuvent etre rejetes. Une premiere analyse dans une gamme d'energie sub-mev des electrons simples totalements contenus est faite en terme de section efficace faible et en terme de moment magnetique du neutrino. Enfin une estimation preliminaire de l'activite du detecteur apres sa remise a niveau
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Marzioni, Maria Francesca. "Axion dark matter and two-neutrino double electron capture searches in the Large Underground Xenon experiment." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31054.
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The hunt for Dark Matter plays a truly critical role in contemporary physics. At both the largest and smallest scales, deep questions are being raised about the fundamental nature of the universe - questions that confirmation and then characterisation of particle dark matter will provide many answers to. This thesis presents some of the world's most sensitive searches to date for certain types of axion dark matter, axion-like particles, and two-neutrino double electron capture. These have been conducted using the Large Underground Xenon (LUX) experiment. Evidence for dark matter and physics beyond the Standard Model of particle physics is described in Chapter 1, while Chapter 2 gives an overview of proposed candidates for particle dark matter. The various experimental approaches being used to detect particle dark matter are presented in Chapter 3. Direct detection with time projection chambers plays a major role in this thesis, with particular interest in the LUX detector, that is described in its components and operations. Chapter 4 presents LUX direct searches for weakly interacting massive particles. Although I have contributed to these analyses, they are included for completeness only, as they are not part of my central work. The LUX collaboration's searches for axion dark matter and axion-like particle have delivered world-leading results on the axion-electron coupling constant. These results, that I personally led and which have been published in Physics Review Letters, are presented in Chapter 5, along with sensitivity studies, also led by me, made for the future LUX-ZEPLIN experiment. Finally, a search for two-neutrino double electron capture of 124Xe, that I performed using LUX data to extract a limit on the half life of the process, is presented in Chapter 6. Although being allowed by the Standard Model, two-neutrino double electron capture shares the matrix element calculation framework with the neutrinoless channel of the same process, becoming of great interest in the scope of neutrino physics. Conclusions follow and close the thesis.
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Smith, Benjamin Mark. "Measurement of the electron neutrino charged-current inclusive cross-section on carbon using the T2K near detector." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/23284.
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T2K is a long baseline neutrino oscillation experiment which uses a beam of muon neutrinos to study muon neutrino disappearance and electron neutrino appearance. The measurement of v_e appearance is sensitive to CP violation, and reducing the systematic uncertainties is critical to enabling experimental determination of whether there is CP violation in the lepton sector. This thesis describes the first measurement of the v_e CC inclusive cross-section on carbon at energies relevant to T2K and other long baseline neutrino oscillation experiments. The T2K near detector, ND280, is used to select a sample of v_e events, and a Bayesian unfolding technique is used to extract differential cross-sections as a function of electron momentum, electron angle and Q^2. The total flux-averaged cross-section is also extracted, and is found to be 1.11 ± 0.20 x 10^{-38} cm^2/nucleon, which agrees well with both the NEUT neutrino interaction generator prediction of 1.23 x 10^{-38} cm^2/nucleon and the GENIE prediction of 1.08 x 10^{-38} cm^2/nucleon. A restricted phase-space analysis is also performed, in which only events where the ejected electron has momentum greater than 550 MeV/c and cos(θ_e) > 0.72 are selected. In this case, the flux-averaged cross-section is found to be 6.54 ± 1.22 x 10^{-39} cm^2/nucleon, again in good agreement with both the NEUT prediction of 7.38 x 10^{-39} cm^2/nucleon and the GENIE prediction of 6.41 x 10^{-39} cm^2/nucleon.
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Laborie, Jean-Marc. "Expérience de diffusion neutrino-électron auprès d'un réacteur nucléaire : étude et développement du détecteur anti-Compton." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10036.
Full textAbstract:
L'experience munu consiste a mesurer la diffusion neutrino-electron aupres d'un reacteur nucleaire du centre de production electrique du bugey. Le detecteur central est une chambre a projection temporelle contenant 1 m#3 de cf#4 gazeux sous 5 bars et le seuil de detection des electrons de recul est place a 500 kev. La chambre est entouree d'un detecteur anti-compton et de blindages passifs. Le detecteur anti-compton est fait de 8 m#3 de scintillateur liquide et de 48 photomultiplicateurs de 20 cm de diametre, avec un seuil en energie de 100 kev. Il permet de detecter la plupart des photons ayant interagi dans le gaz et de porter le taux de bruit de fond a un niveau comparable a celui du signal. D'une part les photomultiplicateurs et l'electronique logique et analogique associee ont ete mis en oeuvre, l'anti-compton a ete assemble et teste. D'autre part, un code de simulation a ete developpe : la collection de lumiere dans l'anti-compton a ete etudiee, l'influence des conditions electroniques de prise de decision sur son efficacite a ete estimee, une methode d'etalonnage a ete proposee.
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Vertongen, Gilles. "The fall and rise of antimatter: probing leptogenesis and dark matter models." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210200.
Full textAbstract:
Big Bang Nucleosynthesis (BBN), together with the analyses of the Cosmic Microwave Background (CMB) anisotropies, confirm what our day to day experience of life attests :antimatter is far less present than matter in the Universe. In addition, these observables also permit to evaluate that there exists about one proton for every 10^{10} photons present in the Universe. This is in contradiction with expectations coming from the standard hot big bang, where no distinction between matter and antimatter is made, and where subsequent annihilations would lead to equal matter and antimatter contents, at a level 10^{−10} smaller than the observed one. The Standard Model of fundamental interactions fails to explain this result, leading us to search for ‘Beyond the Standard Model’ physics.Among the possible mechanism which could be responsible for the creation of such a matter asymmetry, leptogenesis is particularly attractive because it only relies on the same ingredients previously introduced to generate neutrino masses. Unfortunatelly, this elegant proposal suffers from a major difficulty :it resists to any tentative of being probed by our low energy observables. In this thesis, we tackle the problem the other way around and propose a way to falsify this mechanism. Considering the type-I leptogenesis mechanism, i.e. a mechanism based on the asymmetric decay of right-handed neutrinos, in a left-right symmetric framework, we show that the observation of a right-handed gauge boson W_R at future colliders would rule out any possibility for such mechanism to be responsible of the matter asymmetry present in our Universe.
Another intriguing question that analyses of the anisotropies of the CMB confirmed is the presence of a non-baryonic component of matter in our Universe, i.e. the dark matter. As hinted by observations of galactic rotation curves, it should copiously be present in our galactic halo, but is notoriously difficult to detect directly. We can take advantage on the fact that antimatter almost disappeared from our surroundings to detect the contamination of cosmic rays from standard sources the annihilation products of dark matter would produce.
The second subject tackled in this work is the study of the imprints the Inert Doublet Modem (IDM) could leave in (charged) cosmic rays, namely positrons, antprotons and antideuterons. This model, first proposed to allow the Bout-Englert-Higgs particle to evade the Electroweak Precision Test (EWPT) measurements, introduces an additional scalar doublet which is inert in the sense that it does not couple directly to fermions. This latter property brings an additional virtue to this additional doublet :since it interacts weakly with particles, it can play the role of dark matter. This study will be done in the light of the data recently released by the PAMELA, ATIC and Fermi-GLAST collaborations, which reported e^± excesses in two different energy ranges.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Christodoulou, Georgios. "A measurement of the electron neutrino component in the T2K beam using the tracker detectors and the electromagnetic calorimeter at the near detector ND280." Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569512.
Full textAbstract:
Starting with a muon neutrino (vμ) beam T2K is searching for electron neutrino (ve) ap- pearance in the Far Detector (Super-Kamiokande) and aims to produce the first measure- ment of the neutrino mixing angle e13. Beam contamination of Ve is one of the main background components. The Near Detector, ND280, is optimized for measuring the u; contamination through the reconstruction of Ve interactions. The u; beam contamination is studied in this thesis. The total number of Ve beam events reconstructed in ND280 is 51.2 +21.3 stat. +10.1 sys/ -21.3 stat. -14.4 sys for 1.068 x10 to the power of 20 protons on target, a resu t w lC IS consistent with the Monte Carlo expectations. This result a supplementary statement to the vμ -> 7 Ve oscillation signal observed at Super-Kamiokande during the first year of T2K run, as no significant excess in the expected Ve beam contamination has been observed.
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GAGLIARDI, NADINE. "Developpement et mise au point du detecteur hellaz1 : detection individuelle des electrons issus d'un nuage d'ionisation (elaboration du projet hellaz pour la detection de neutrinos solaires)." Paris 6, 1999. http://www.theses.fr/1999PA066199.
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Certaines experiences peuvent mesurer le flux de neutrinos solaires pondere selon une certaine fonction de l'energie mais elles ne peuvent pas mesurer la distribution en energie des neutrinos. L'experience hellaz (helium a la temperature de l'azote liquide) se propose d'apporter des resultats complementaires aux experiences de neutrinos solaires deja existantes. Elle mesurera le spectre de neutrinos solaires a basse energie (0. 2 mev
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Guillemin, Thibault. "Vers une mesure de la section efficace de production inclusive du boson W en électron-neutrino dans l'expérience ATLAS au LHC." Chambéry, 2009. http://www.theses.fr/2009CHAMS019.
Full textAbstract:
Le boson charge W sera abondamment produit au Large Hadron Collider (LHC) dans des collisions proton-proton à une énergie dans le centre de mass de 14 TeV : sa fréquence de production est 1 Hz à basse luminosité. Sa désintégration dans le canal électron aura une signature claire dans le détecteur ATLAS, marquée par un électron de haute impulsion transverse et une énergie transverse manquante élevée. Le détecteur ATLAS est un détecteur généraliste constitué d'un détecteur de traces, d'un calorimètre électromagnétique, d'un calorimètre hadronique et d'un spectromètre à muon. Entièrement installé dans sa caverne, il a enregistré des données avec le premier faisceau du LHC en septembre 2008. Une première partie de la thèse consiste dans le développement d'une stratégie d'analyse pour la mesure de la section efficace de production inclusive du boson W avec les premières données d' ATLAS, maximisant l'utilisation des données par rapport aux simulations Monte-Carlo. Les principales sources d'incertitude systématique sont mises en évidence et étudiées : une précision sur la mesure meilleure que 10% sera accessible des la première phase de l'expérience. Une seconde partie est consacrée à l'alignement en temps des canaux de lecture des calorimètres à argon liquide, étape nécessaire pour atteindre les performances nominales. Des constantes de temps sont calculées à partir des données enregistrées en septembre 2008 : elles permettront d'assurer un alignement en temps à 2-3 ns de tous les canaux pour les premières collisionsThe charged W-boson will be abundantly produced at the Large Hadron Collider (LHC) in proton-proton collisions at a center-of-mass energy of 14 TeV : its frequency production is 1 Hz at low luminosity. Its decay in the electron channel will have a clear signature in the ATLAS detector, defined by a high transverse momentum electron and a high missing transverse energy. The ATLAS detector is a multi-purposes detector made up of a tracker, an electromagnetic calorimeter, a hadronic calorimeter and a muon spectrometer. It is fully installed in its cavern and recorded data with the first LHC beam in September 2008. A first part of the thesis presents a full analysis strategy for the W-boson inclusive production cross section with the first ATLAS data, maximizing the inputs from real data with respect to simulated ones. The main contributions to the systematical uncertainty are identified and estimated : a measurement precision better than 10% will be reachable from the first phase of the experiment. A second part is dedicated to the time alignment of the liquid argon calorimeters readout channels, a required step to reach the nominal performances. Timing constants are computed from the data recorded in September 2008 : they will allow a time alignment of all channels at a 2-3 ns level for the start-up
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Scielzo, Nicholas David. "Measurement of the beta-neutrino correlation in laser trapped {sup 21}Na." Berkeley, Calif. : Oak Ridge, Tenn. : Lawrence Berkeley National Laboratory ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/821455-YDxgQ2/native/.
Full textAbstract:
Thesis (Ph.D.); Submitted to Univ. of California, Berkeley, CA (US); 1 Jun 2003.Published through the Information Bridge: DOE Scientific and Technical Information. "LBNL--54350" Scielzo, Nicholas David. USDOE Director. Office of Science. Nuclear Physics (US) 06/01/2003. Report is also available in paper and microfiche from NTIS.