Neste projeto realizamos um estudo sobre as fórmulas de probabilidades de oscilação de neutrinos na matéria em duas e três gerações. Estudamos extensivamente a fenomenologia e os experimentos de oscilação de neutrinos. Além de rever todas as expressões analíticas para as soluções exatas e aproximadas conhecidas na literatura para as probabilidades de conversão, também desenvolvemos soluções novas. Mostramos que os mesmos potenciais que possuem solução exata em duas gerações, também possuem em três. Com o formalismo proposto nesta dissertação para resolução da equação de evolução dos neutrinos na matéria, fica descartada a existência de outros potenciais, que não os aqui discutidos, com solução analítica em termos de funções que são obtidas como casos especiais ou limites da função hipergeométrica generalizada. / In this project we realized a study about the formulas of neutrino oscillation probabilities in matter in two and three generations. We studied the neutrino oscillation phenomenology and its experiments. We reviewed all the analytic expressions to the exact and aproximate solutions known at the literature to the conversion probabilities, as well as we have developed new ones. We showed that the same potentials which have exact solutions in two generations, also have exact solutions in three generations. By using the proposed formalism in this dissertation to the resolution of the evolution equation of neutrinos in matter, we ruled out the existence of other potentials not discussed here that have exact solution in terms of the special functions that are special cases or limits of the generalized hypergeometric function.

[pt] Em física de neutrinos, quase todos os dados de experimentos importantes podem ser explicados através de oscilação de neutrinos causados por massas e misturas. Porem, existe a possibilidade de que os neutrinos tenham algumas propriedades, além dessas mencionadas, que manifesta alguma física nova ou física além do modelo padrão. Esta nova física pode ser explicada por partículas exóticas ainda desconhecidas que são responsáveis por interações extras ou interação não padrão com os neutrinos e aqui as estudaremos fenomenologicamente, isto é, não nos preocuparemos com um modelo teórico em si. Nesta tese, estudamos os efeitos dessa interação não-padrão de neutrinos com a matéria para os experimentos de oscilação de grandes comprimentos. Nós consideramos dois detetores idênticos, mas com suas distâncias em relação à fonte, diferentes em dois casos: Primeiro, estudamos o potencial para sondar os efeitos de interação não-padrão para experimentos que usam feixes de neutrinos convencionais vindo de decaimentos de píons. Como exemplo, consideramos um feixe de neutrinos a ser criado pelo acelerador de prótons do JPARC (Japan Proton Accelerator Research Complex) no Japão. Nele, consideramos dois detetores, além do detetor próximo ao JPARC para monitorar o feixe; temos o primeiro que está situado em Kamioka, Japão e o outro em algum lugar na Coréia do Sul, sendo que o primeiro está a 295 km, enquanto o segundo está em torno de 1000 km do JPARC. Segundo, avaliamos também o potencial da fábrica de neutrinos, o qual utiliza feixes de neutrinos vindo do decaimento de múons armazenados num anel para estudar os parâmetros de interação não-padrão e o seu impacto na sensibilidade da fase de violação CP e o ângulo de mistura 013. Neste trabalho, também combinamos os dados simulados com dois detetores com comprimentos diferentes, sendo o primeiro a 3000 km e o outro a 7000 km da fonte. O comprimento deste segundo detetor foi escolhido pelo fato de ter uma característica peculiar, o Magic Baseline (comprimento mágico), onde a probabilidade de oscilação não depende da fase de violação de CP quando os parâmetros não-padrão estão ausentes. / [en] In neutrino physics, most of the experimental data importants can be explained due to neutrino oscilation induced by mass and mixing. However, there is the posibility that the neutrinos have some properties, new physics or beyond Standard Model. This new physics can be explained with some so far unknown exotic particles that are responsables for extra interactions ornon standard interaction with neutrinos and here we studied fenomenologically, without concerning about any theoretical model. In this Thesis, we study the effects of Non Standard Interaction (NSI) with matter in experimentsof oscilation in long baseline. We consider two identical detectors, but wih diferent baselines from source, in two cases: first, we study the probing potencial to analyse the NSI effect for experiments that use conventionalneutrino beams coming from pions decay. For example, we should consider a neutrino beam created at the Proton Accelerator JPARC (Japan Proton Accelerator Research Complex) in Japan. We consider two detectors, in additionto the front detector at JPARC to monitor the beam; we have the first in Kamioka, Japan and other somewhere in Korea, the first is at 295km, and the second is localizate about 1000 km from JPARC. In sequence, we also evaluate the potencial of Neutrino Factory, where a neutrino beam come from a muon decay storage ring, in order to study the non standard interactions parameter and its impact in CP phase sensibility and the mixingangle 013. In this work we combined theses simulated data from two detectors with differents baselines, with the first localized at 3000 km and the other at 7000 km from the source. The baseline of this second detectorwas chosen because it has a special feature, the Magic Baseline, where theoscilation probability do not depend of CP phase violation when the nonstandard parameters are absent.

Identifying what makes up the Dark Matter is a long-standing problem to which the abundance of gravitational and cosmological evidence fails to answer. Indirect detection techniques have the aim to unveil the nature of Dark Matter by catching and identifying the products of potential decays and/or annihilations. The work exposed in this thesis is in line with this strategy and has for common thread the quest for line(-like) features in the extraterrestrial fluxes of gamma-rays and neutrinos. The motivation behind this specific interest is that, due to the absence of astrophysical counterparts beyond the GeV scale, these features constitute the ultimate probes (also called “smoking guns”) of the existence of Dark Matter.The thesis is organized in three Parts, the first of which is an introduction to the different facets of the Dark Matter conundrum and why it is not a trivial issue. The works involving gamma-ray line considerations are gathered in Part II, and those exclusively focusing on neutrino lines in Part III.Part II focuses on the effective field theory of Dark Matter decay, first in the context of millicharged particles decaying to gamma-ray lines, and then in the context of (neutral and millicharged) Dark Matter decays involving the simultaneous emission of gamma-ray and neutrino lines. In both cases, the simultaneous emission of cosmic rays is unavoidable and the decays are constrained in a multi-messenger fashion. The complementarity of the results obtained is used to derive model-independent constraints on the Dark Matter lifetime, and shows the possibility to exclude or distinguishsome specific scenarios on the basis of an explicit experimental conjecture.After an introduction to the neutrino detection principles and to the operation of the IceCube detector, Part III focuses on two careful searches for spectral features in the neutrino spectrum. The main goal behind these analyses, conducted in two different regions of the energy spectrum but using the same likelihood ratio procedure, is to popularize dedicated energy distribution studies by showing their ability to reach sensitivity levels comparable to—sometimes even going beyond—those obtained with angular distribution studies or even in the context of gamma-ray line searches. / Option Physique du Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Orientador: Marcelo Moraes Guzzo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T07:13:46Z (GMT). No. of bitstreams: 1 Costa_RafaelNobertoAlmeidada_M.pdf: 2184656 bytes, checksum: 96104bbac452f3b0ec1bab401b55bf0a (MD5) Previous issue date: 2014 / Resumo: Apresentamos neste trabalho um review descrevendo a oscilações de neutrinos quando é levado em conta a violação da simetria de carga paridade (CP). Por conta disso abordaremos a origem da violação de CP no Modelo Padrão das Partículas Elementares, desde a sua descoberta no sistema dos mésons káons neutros (K°) ,até a sua inclusão dentro do Modelo Padrão, a qual foi desenvolvida por Kobayashi e Maskawa. Depois de entendermos a violação de CP passamos a tratar das oscilações de neutrinos e como esta violação é incluída no modelo. Abordamos o modelo utilizando os dados mais recentes dos parâmetros para as oscilações de neutrinos, incluindo a recente medição do ângulo de mistura ?13. Utilizando estes dados e os resultados obtidos a partir do modelo de oscilações de neutrinos inferimos um limite para a fase de violação de CP, dado por nós como sendo ?CP= 19 ^{+19°}_{-9°} com 1? de C.L. / Abstract: In this work was make a review describing the neutrino oscillations when is taken in account the charge parity symmetry violation (CP). Because of that we will approach the origin of CP violation in Standard Model of Elementary Particles, since its discovery in the neutral kaons meson system (K°), until its inclusion within the Standard Model, made by Kobayashi and Maskawa. After we understand the CP violation we treat the neutrino oscillations and how this violation is included in the model. We approach the model using the most recent data of the parameters from neutrino oscillations, including the recent data measured to the mixing angle ?13. Utilizing this data, and the data obtained from the model of neutrino oscillation, we infer a limit to the CP violation phase, given by us as being ?CP= 19^{+19°}_{-9°} with 1? of C.L. / Mestrado / Física / Mestre em Física

The IceCube Neutrino Observatory has sensitivity to MeV electron antineutrinos from core-collapse supernovae through an excess of the detection rate over the background. Wavelength-shifting sensors have the potential to greatly increase photon collection making it a promising candidate for improving the measurement of the supernova neutrino light curve in IceCube-Gen2. For high-energy neutrino reconstruction, the competing effect of increased photon collection and the broader time distribution necessitate detailed simulations to determine the impact. In this thesis, we investigate the sensitivity gain caused by wavelength shifters in a future IceCube-Gen2 detector regarding the detection of faint modulations of the supernova neutrino lightcurve. Furthermore, we lay the groundwork for a future high-energy reconstruction through the implementation and integration of wavelength-shifting sensors into the IceCube simulation framework.

No description available.

In this thesis, we review the basics of phenomenology in particle physics at neutrino beam dump experiments and hadron colliders. We then consider the phenomenology of various new particles, with masses between 1 MeV and 1 TeV, at the intensity and energy frontiers. We perform sensitivity analyses for physics beyond the standard model at particle colliders (LEP and LHC) and a number of past and future neutrino beam dump experiments (SHiP, DUNE, LSND, MicroBooNE, MiniBooNE and SBND). In particular, we motivate searches for new heavy neutral leptons in single photon events at neutrino and collider experiments (and also via supernova cooling), millicharged particles in single electron events at neutrino experiments, lepton flavor violating scalars via standard model induced mixed flavor neutrino trident production at neutrino experiments, and colored scalar doublets at colliders in events with many jets, soft leptons and low missing energy. In the process, we set novel new bounds on the parameters of these theories and propose powerful new searches that can be performed. We also motivate the construction of a new detector at the LHC called milliQan, and perform a full Geant4 simulation to calculate its projected sensitivity for millicharged particles. The milliQan experiment has since been approved and is currently undergoing construction. / Thesis / Doctor of Philosophy (PhD) / In this thesis, we review the basics of particle physics at neutrino experiments and particle colliders. We then motivate and develop key searches that can be performed to look for new particles at a series of existing and future experiments. We focus on new particles with masses between the electron mass and 1000 times the proton mass. The many searches we consider involve looking for processes that produce a single ray of light, a single electron, a pair of oppositely charged "electron-like" events, new collider signatures, and/or modifications of star explosions. In the process, we set novel new bounds on many theories. We also motivate the construction of a new detector at the Large Hadron Collider called milliQan, and perform a full simulation to assess its future performance. The milliQan experiment has since been approved and is currently undergoing construction.

<p dir="ltr">Anomalous oscillations in beta-decay have been noticed in data sets across the world, from many different investigators, and in the widest array of instrument types. Scientific literature contains many references to the phenomena which often includes annual periodicities with phase relationship to the earth’s annual orbit about the sun as well as solar-mechanical periodicities which relate to the internal motions of the sun. Over time two camps have appeared in the literature - those who hold that the signals are due to environmental effects or instrument errors, and those who propose new physics based on solar neutrino flux.</p><p dir="ltr">Here, with a combination of literature review, published experiments, previously unpublished laboratory experiment, and computational machine learning prediction, we advance toward answering the question of which of these two competing hypotheses are correct and propose a design for the next generation of experimental apparatus.</p>

Das Standardmodell (SM) der Teilchenphysik hat sich in der Praxis als vielseitige Theorie bewährt, dennoch deuten nichtverschwindende Neutrinomassen, dunkle Materie und Baryonenasymmetrie auf Physik jenseits des SM (BSM) hin. Um also ein mit den Beobachtungen konsistentes Modell zu entwickeln, ist eine umfassendere Theorie nötig. Experimentell kann entweder in Abweichungen von den Vorhersagen des SM nach neuer Physik gesucht werden. So kann jedes BSM-Szenario getestet werden. In dieser Arbeit werden BSM-Szenarien im Quark- sowie im Leptonen-Sektor und deren phänomenologische Konsequenzen auf messbare Observablen betrachtet. Ein konkretes Beispiel in dieser Dissertation sind Neutrino massen modellierung mit der Einführung von sterilen Neutrinos. Wir untersuchen die phänomenologische Konsequenz ihrer Einführung auf verschiedenen Massenskalen im Zusammenhang mit symmetriegenerierten oder strukturlosen Neutrinomassenmodellen. Unter den geschmacksabhängigen aktivsterilen Mischungen in den durch Symmetrie erzeugten Massenmodellen finden wir deutliche Hierarchien, die als Modelldiskriminator für zukünftige Experimente dienen. Ähnlich wie beim Ausnutzen von Symmetrien im Neutrinosektor, kann man Symmetrien auch in Modellen für Quarkmassen nutzen. In dieser Arbeit werden Symmetrien behandelt, die den Cabibbo-Winkel für Quarkmischung in führender Ordnung quantisieren können. Dies führt zu einer Vielzahl möglicher Symmetrien, welche genutzt werden können um spezifische Modelle für Quarkmassen zu entwickeln. BSM-Physik indirekt mit Hilfe astrophysikalischer Neutrinos zu testen stellt eine Alternative zur direkten Detektion dar, und führt bei Betrachtung der Zusammensetzung des NeutrinoFlavours zu klaren Abweichungen von den Erwartungen. Neben der Behandlung verschiedenster BSM-Szenarien wird auch das Potenzial zukünftiger Experimente betrachtet, vor Allem im Hinblick auf deren Effektivität Physik jense. / The Standard Model (SM) of particle physics is a well-tested and predictive theory, however non-zero neutrino masses, the existence of dark matter, and the baryon asymmetry suggest physics beyond the SM. Thus, in order to have a model consistent with observations, a more complete theory is needed. Experimentally, one can search for new physics, thereby differentiate different BSM scenarios. We consider BSM scenarios in the quark and lepton sectors, and study their phenomenological consequence on measurable observables. A specific example is neutrino mass modeling with the introduction of sterile neutrinos. We study the phenomenological consequence of introducing them at different mass scales in the context of symmetry-generated or structureless neutrino mass models. We find distinct hierarchies among the flavor-dependent active-sterile mixings in the symmetry-generated mass models, which acts as a model discriminator for future experiments. Similarly as using symmetries in the neutrino sector, one can also use symmetries in quark mass models. This thesis consider symmetries capable of quantizing the Cabibbo quark mixing angle to leading order. As a result, a variety of possible symmetries are obtained, which can be used to build specific quark mass models. Probing BSM physics indirectly via astrophysical neutrinos, acts as an alternative to direct detection, and using the neutrino flavor composition as observable, BSM physics leads to clear deviations from expectation. Additional information comes from other effects, and it helps in constraining the parameter space further. Beside discussing different BSM scenarios, we illustrate the potential of future experiments, emphasizing their effectiveness to test and discriminate BSM physics.

The search for the neutrinoless double beta (0nbb) decay is one of the most active fields in modern particle physics. This process is not allowed within the Standard Model and its observation would imply lepton number violation and would lead to the Majorana nature of neutrinos. The experimentally observed quantity is the half-life of the decay, which can be connected to the effective Majorana neutrino mass via nuclear matrix elements. The latter can only be determined theoretically and are currently affected by large uncertainties. To reduce these uncertainties one can investigate the well established two-neutrino double beta (2nbb) decay into the ground and excited states of the daughter isotope. These similar processes are allowed within the Standard Model. In this dissertation, the search for 2nbb decays into excited states is performed in Pd-110, Pd-102 and Ge-76. Three gamma spectroscopy setups at the Felsenkeller (Germany), HADES (Belgium) and LNGS (Italy) underground laboratories are used to search for the transitions in Pd-110 and Pd-102. No signal is observed leading to lower half-live bounds (90% C.I.) of 2.9e20 yr, 3.9e20 yr and 2.9e20 yr for the 0/2nbb 2p1, 0p1 and 2p2 transitions in Pd-110 and 7.9e18 yr, 9.2e18 yr and 1.5e19 yr for the 0/2nbb 2p1, 0p1 and 2p2 transitions in Pd-102, respectively. This is a factor of 1.3 to 3 improvement compared to previous limits. The data of Phase I (Nov 2011 - May 2013) of the 0nbb decay experiment GERDA at LNGS is used to search for excited state transitions in Ge-76. The analysis is based on coincidences between two detectors and finds no signal. Lower half-life limits (90 % C.L.) of 1.6e23 yr, 3.7e23 yr and 2.3e23 yr are obtained for the 2nbb 2p1, 0p1 and 2p2 transitions, respectively. These limits are more than two orders of magnitude larger than previous ones and could exclude many old matrix element calculations. In addition to the excited state searches, important measurements and improvements for GERDA Phase II upgrades are performed within this dissertation. 30 new BEGe detectors are characterized for their surface and active volume properties which is an essential ingredient for all future physics analyses in GERDA. These precision measurements reduce the systematic uncertainty of the active volume to a subdominant level. In extension to this, a new model for simulating pulse shapes of n+ electrode surface events is developed. With this model it is demonstrated that the dominant background of K-42 on the detector surfaces can be suppressed by a factor of 145 with an A/E pulse shape cut in Phase II. A further suppression of background is obtained by a liquid argon scintillation light veto. With newly developed Monte Carlo simulations, including the optical scintillation photons, it is demonstrated that Tl-208 in the detectors holders can be suppressed by a factor of 134. K-42 homogeneously distributed in the LAr can be suppressed with this veto in combination with pulse shape cuts by a factor of 170 for BEGe detectors. The characterization measurements and the developed simulation tools presented within this dissertation will help to enhance the sensitivity for all 0/2nbb decay modes and will allow to construct an improved background model in GERDA Phase II. / Die Suche nach dem neutrinolosen Doppelbetazerfall (0nbb) ist eines der aktivsten Felder der modernen Teilchenphysik. Der Zerfall setzt die Verletzung der Leptonenzahl voraus und hätte die Majorananatur des Neutrinos zur Folge. Die durch eine Beobachtung bestimmbare Halbwertszeit des Zerfalls ermöglicht, über ein nukleares Matrixelement, Zugang zur effektiven Majorananeutrinomasse. Die größten Unsicherheiten gehen dabei auf das Matrixelement zurück, welches nur durch verschiedene, teilweise stark voneinander abweichende theoretische Modelle zugänglich ist. Eine Möglichkeit diese Unsicherheiten zu reduzieren bieten genaue Studien des im Standardmodel erlaubten neutrinobegleiteten Doppelbetazerfalls (2nbb) in angeregte Zustände des Tochterkerns. In dieser Dissertation wird der 2nbb-Zerfall der Nuklide Pd-110, Pd-102 und Ge-76 in angeregte Zustände untersucht. Die Untersuchungen von Pd-110 und Pd-102 wurden in drei umfangreichen Gammaspektroskopie-Experimenten in den Untergrundlaboren Felsenkeller (Deutschland), HADES (Belgien) und LNGS (Italien) durchgefürt. Es wurde kein Signal beobachtet und damit die weltweit besten unteren Grenzen für die Halbwertszeit dieser Zerfälle festgesetzt: 2,9e20 yr, 3,9e20 yr und 2,9e20 yr für die 0/2nbb 2p1, 0p1 und 2p2 Übergänge in Pd-110 and 7,9e18 yr, 9,2e18 yr und 1,5e19 yr für die 0/2nbb 2p1, 0p1 und 2p2 Übergänge in Pd-102 (90% C.I.). Dies ist eine 1,3 bis 3-fache Verbesserung gegenüber den vorher bekannten Grenzen. Die Untersuchung des 2nbb-Zerfalls in Ge-76 basiert auf Daten aus Phase I (Nov. 2011 - Mai 2013) des 0nbb-Zerfall Experiments GERDA. Mit der auf koinzidenten Ereignissen basierten Analyse konnte kein Signal beobachtet werden und folgende untere Grenzen für die Halbwertszeit der 2nbb 2p1, 0p1 und 2p2 Übergänge wurden festgelegt: 1,6e23 yr, 3,7e23 yr und 2,3e23 (90% C.L.). Diese 100-fache Verbesserung gegenüber den bisher bekannten Grenzen widerlegt eine Vielzahl älterer, zur Verfügung stehender Matrixelemente. Zusätzlich wurden im Rahmen dieser Dissertation für die Erweiterungen des GERDA Experiments zur Phase II wichtige Messungen durchgeführt und Verbesserungen entwickelt. 30 neu produzierte BEGe Detektoren wurden hinsichtlich ihrer Oberflächeneigenschaften sowie ihrer aktiven Volumina charakterisiert. Diese Präzisisionsmessungen sind für alle zukünftigen Analysen in GERDA notwendig und erlauben die entsprechenden systematischen Unsicherheiten auf ein subdominantes Niveau zu reduzieren. Erweiternd wurde ein neues Model zur Beschreibung der n+ Elektrode entwickelt, welches erstmals erlaubt die Pulsform von Oberflächeninteraktionen zu simulieren. Mithilfe dieses Models konnte demonstriert werden, dass der in Oberflächeninteraktionen begründete und in GERDA dominante Messuntergrund von K-42 auf der Detektoroberfläche durch Pulsformanalyse um das 145-fache unterdrückt werden kann. Eine weitere Untergrundreduzierung wird durch ein Flüssigargon Szintillationsveto erreicht. Im Rahmen dieser Arbeit wurden vorhandene Monte Carlo Simulationen um den Transport von optischen Photonen erweitert und die 134-fache Unterdrückung des Tl-208 Untergrundes demonstriert. Die Ergebnisse dieser Arbeit helfen eine deutliche Sensitivitätsverbesserung für die zuküntige Suche nach dem 0/2nbb-Zerfall zu erzielen und erlauben die Erstellung eines präziseren Untergrundmodels in GERDA Phase II.