Thèses sur le sujet « Planar cluster »

This thesis generalizes and interprets Kesten\'s Incipient Infinite Cluster (IIC) measure in two ways. Firstly we generalize Járai\'s result which states that for planar lattices the local configurations around a typical point taken from crossing collection is described by IIC measure. We prove in Chapter 2 that for backbone, lowest crossing and set of pivotals, the same hold true with multiple armed IIC measures. We develop certain tools, namely Russo Seymour Welsh theorem and a strong variant of quasi-multiplicativity for critical percolation on 2-dimensional slabs in Chapters 3 and 4 respectively. This enables us to first show existence of IIC in Kesten\'s sense on slabs in Chapter 4 and prove that this measure can be interpreted as the local picture around a point of crossing collection in Chapter 5.

We determine the mass scale of Planck galaxy clusters using gravitational lensing mass measurements from the Cluster Lensing And Supernova survey with Hubble (CLASH). We have compared the lensing masses to the Planck Sunyaev-Zeldovich (SZ) mass proxy for 21 clusters in common, employing a Bayesian analysis to simultaneously fit an idealized CLASH selection function and the distribution between the measured observables and true cluster mass. We used a tiered analysis strategy to explicitly demonstrate the importance of priors on weak lensing mass accuracy. In the case of an assumed constant bias, b(SZ), between true cluster mass, M-500, and the Planck mass proxy, M-PL, our analysis constrains 1 - b(SZ) = 0.73 +/- 0.10 when moderate priors on weak lensing accuracy are used, including a zero-mean Gaussian with standard deviation of 8% to account for possible bias in lensing mass estimations. Our analysis explicitly accounts for possible selection bias effects in this calibration sourced by the CLASH selection function. Our constraint on the cluster mass scale is consistent with recent results from the Weighing the Giants program and the Canadian Cluster Comparison Project. It is also consistent, at 1.34 sigma, with the value needed to reconcile the Planck SZ cluster counts with Planck's base Lambda CDM model fit to the primary cosmic microwave background anisotropies.

We present the all-sky Planck catalogue of Sunyaev-Zeldovich (SZ) sources detected from the 29 month full-mission data. The catalogue (PSZ2) is the largest SZ-selected sample of galaxy clusters yet produced and the deepest systematic all-sky survey of galaxy clusters. It contains 1653 detections, of which 1203 are confirmed clusters with identified counterparts in external data sets, and is the first SZ-selected cluster survey containing > 10(3) confirmed clusters. We present a detailed analysis of the survey selection function in terms of its completeness and statistical reliability, placing a lower limit of 83% on the purity. Using simulations, we find that the estimates of the SZ strength parameter Y-5R500 are robust to pressure-profile variation and beam systematics, but accurate conversion to Y-500 requires the use of prior information on the cluster extent. We describe the multi-wavelength search for counterparts in ancillary data, which makes use of radio, microwave, infra-red, optical, and X-ray data sets, and which places emphasis on the robustness of the counterpart match. We discuss the physical properties of the new sample and identify a population of low-redshift X-ray under-luminous clusters revealed by SZ selection. These objects appear in optical and SZ surveys with consistent properties for their mass, but are almost absent from ROSAT X-ray selected samples.

Cette thèse s'inscrit dans l'étude mathématique de la percolation, qui regroupe une famille de modèles présentant une transition de phase. Des avancées majeures au cours des quinze dernières années, notamment l'invention du SLE et la preuve de l'invariance conforme de la percolation de Bernoulli critique, nous permettent aujourd'hui d'avoir une image très complète de la percolation de Bernoulli sur le réseau triangulaire. Cependant, de nombreuses questions demeurent ouvertes, et ont motivé notre travail.La première d'entre elle est l'universalité de la percolation plane, qui affirme que les propriétés macroscopiques de la percolation plane critique ne devraient pas dépendre du réseau sous-jacent à sa définition. Nous montrons, dans le cadre de la percolation Divide and Color, un résultat qui va dans le sens de cette universalité et identifions, dans ce contexte, des phénomènes macroscopiques indépendants du réseau microscopique. Une version plus faible d'universalité est donnée par la théorie de Russo-Seymour-Welsh (RSW), et sa validité est connue pour la percolation de Bernoulli (sans dépendance) sur les réseaux plans suffisamment symétriques. Nous étudions de nouveaux arguments de type RSW pour des modèles de percolation avec dépendance. La deuxième question que nous avons abordée est celle de l'absence d'une composante connexe ouverte infinie au point critique, une question importante du point de vue physique, puisqu'elle traduit la continuité de la transition de phase. Dans deux travaux en collaboration avec Hugo Duminil-Copin et Vladas Sidoravicius, nous montrons que la transition de phase est continue pour la percolation de Bernoulli sur le graphe Z^2x{0,...,k}, et pour la percolation FK sur le réseau carré avec paramètre q inférieur ou égal à 4. Enfin, la dernière question qui nous a guidés est la localité du point critique : la donnée des boules de grands rayons d'un graphe suffit-elle à identifier avec une bonne précision la valeur du point critique? Dans un travail en collaboration avec Sébastien Martineau, nous répondons de manière affirmative à cette question dans le cadre des graphes de Cayley de groupes abéliens.

Le problème de tournées de véhicules (Vehicle Routing Problem - VRP) est un problème d'optimisation combinatoire utilisé généralement pour modéliser et résoudre des différents problèmes rencontrés dans les systèmes logistiques et de transport. Dans cette thèse, nous nous sommes intéressés à l'étude et la résolution d'une classe de problèmes du VRP appelée les problèmes de courses d'orientation (Team Orienteering Problem - TOP). Dans cette catégorie de problèmes, il est a priori impossible de visiter tous les clients en raison de ressources limitées. On associe plutôt un profit à chaque client qui représente sa valeur. Ce profit est collecté lorsque le client est visité par l'un des véhicules disponibles. L'objectif est donc de sélectionner un sous ensemble de clients à servir tout en maximisant le profit total collecté. Dans un premier temps, nous avons introduit une nouvelle généralisation pour le TOP que nous avons appelé le Clustered TOP ou CluTOP. Dans cette variante, les clients sont regroupés en sous-ensembles appelés clusters auxquels nous associons des profits. Pour résoudre cette variante, nous avons proposé un schéma exact basé sur l'approche des plans sécants avec des inégalités valides supplémentaires et des pré-traitements. Nous avons également conçu une méthode heuristique basée sur l'approche order first-cluster second. Cette heuristique hybride combine une heuristique de type Adaptive Large Neighborhood Search qui explore l'espace des solutions et une procédure de découpage qui explore l'espace de recherche des tours géants. De plus, la procédure de découpage est renforcée par une recherche locale afin de mieux explorer l'espace de recherche. Le deuxième problème traité dans ce travail s'appelle le Synchronized Team Orienteering Problem with Time Windows (STOPTW). Cette variante avait été initialement proposée afin de modéliser des scénarios liés à la protection des infrastructures stratégiques menacées par l'avancée des feux de forêts. En plus des contraintes de fenêtres de temps et des visites synchronisées, cette variante considère le cas d'une flotte de véhicules hétérogène. Pour résoudre ce problème, nous avons proposé une méthode heuristique basée sur l'approche GRASP×ILS qui est parvenue à dominer la seule approche existante dans la littérature. La dernière variante du TOP abordée dans cette thèse s'appelle le Set Orienteering Problem (SOP). Les clients dans cette variante sont regroupés en sous-ensembles appelés clusters. Un profit est associé à chaque groupe qui n'est obtenu que si au moins un client est desservi par le véhicule disponible. Nous avons proposé une méthode de coupes avec deux procédures de séparation pour séparer les contraintes d'élimination des sous-tours. Nous avons également proposé un algorithme Mémétique avec une procédure de découpage optimale calculée à l'aide de la programmation dynamique
The Vehicle Routing Problem (VRP) is a family of Combinatorial Optimization Problems generally used to solve different issues related to transportation systems and logistics. In this thesis, we focused our attention on a variant of the VRP called the Team Orienteering Problem (TOP). In this family of problems, it is a priory impossible to visit all the customers due to travel time limitation on vehicles. Instead, a profit is associated with each customer to represent its value and it is collected once the customer is visited by one of the available vehicles. The objective function is then to maximize the total collected profit with respect to the maximum travel time. Firstly, we introduced a new generalization for the TOP that we called the Clustered TOP (CluTOP). In this variant, the customers are grouped into subsets called clusters to which we associate profits. To solve this variant, we proposed an exact scheme based on the cutting plane approach with additional valid inequalities and pre-processing techniques. We also designed a heuristic method based on the order first-cluster second approach for the CluTOP. This Hybrid Heuristic combines between an ANLS heuristic that explores the solutions space and a splitting procedure that explores the giant tours search space. In addition, the splitting procedure is enhanced by local search procedure in order to enhance its coverage of search space. The second problem treated in this work is called the Synchronized Team Orienteering Problem with Time Windows (STOPTW). This variant was initially proposed in order to model scenarios related to asset protection during escaped wildfires. It considers the case of a heterogeneous fleet of vehicles along with time windows and synchronized visits. To solve this problem, we proposed a heuristic method based on the GRASP×ILS approach that led to a very outstanding results compared to the literature. The last variant of the TOP tackled in this thesis called the Set Orienteering Problem (SOP). Customers in this variant are grouped into subsets called clusters. Each cluster is associated with a profit which is gained if at least one customer is served by the single available vehicle. We proposed a Branch-and-Cut with two separation procedures to separate subtours elimination constraints. We also proposed a Memetic Algorithm with an optimal splitting procedure based on dynamic programming

Tesis para optar al grado de Doctor en Ingeniería de Minas
Una característica común en la minería que se realiza en roca competetente es la sismicidad inducida. Esta es resultado de los cambios en los esfuerzos y el fallamiento de la roca alrededor de las excavaciones mineras. Posterior a un evento sísmico, existe un aumento en los niveles de sismicidad que gradualmente decaen con el tiempo, conocido como una secuencia de réplicas. Restringir el acceso a las áreas de la mina por el tiempo suficiente que permita que ocurra este decaimiento de los eventos sísmicos es el enfoque principal de los protocolos de re entrada. Las propiedades estadísticas de las secuencias de réplicas pueden ser estudiadas mediante tres relaciones o leyes sísmicas: (1) Ley de Gutenberg Richter, (2) Ley de Omori Modificada (MOL) para el decaimiento temporal de la sismicidad, y (3) Ley de Båth para la magnitud de la réplica de mayor magnitud. Esta tesis contiene tres partes principales: estimación y correlaciones de los parámetros de las leyes sísmicas para secuencias de réplicas inducidas por la minería, desarrollo de protocolos de re entrada en el espacio tiempo magnitud y el reconocimiento y comportamiento temporal de secuencias de réplicas usando un aglomeramiento espacio tiempo. En la primera parte, se aplicaron las tres leyes sísmicas, además del modelo estocástico de Reasenberg Jones, para estudiar los parámetros de 11 secuencias sísmicas inducidas por la minería en cuatro minas en Ontario, Canadá. Para proporcionar directrices para el desarrollo del protocolo de re entrada, se estudió y aplicó la dependencia de esto parámetros con la magnitud del evento sísmico principal de la secuencia sísmica. Los resultados obtenidos son coincidentes con los que diferentes autores han estimado en sismicidad tectónica. Sin embargo, aparecen algunas "diferencias de escala", especialmente con el valor b de Gutenberg Richter y el valor p de la ley modificada de Omori, encontrando que, en promedio, hay diferencias de +0.35 y -0.2 respectivamente entre los resultados de la sismicidad inducida y tectónica. La segunda parte corresponde al desarrollo de un protocolo estocástico de re entrada en el espacio tiempo magnitud, utilizando las relaciones entre los parámetros sísmicos inducidos y la magnitud del evento principal. Se define un radio de exclusión y una relación entre el tiempo de máxima curvatura y la magnitud del evento principal. Esto permite construir curvas de decaimiento sísmico, proporcionando información sobre los patrones de decaimiento de una secuencia en curso. Finalmente, se propone un rango de probabilidad de ocurrencia de la réplica de mayor magnitud, basado en el modelo de probabilidad de Reasenberg Jones. La última parte consiste en analizar el comportamiento del agrupamiento de la sismicidad inducida por la minería a través del tiempo y el espacio. Usando el criterio estadístico de Akaike para seleccionar los parámetros del aglomeramiento espacio tiempo, fue posible identificar una secuencia de réplicas asociada a un evento principal con magnitud Mw = 0.7. Además, se encontró que la distancia espacio tiempo aparentemente disminuye su valor antes de que ocurra un evento principal, para luego retornar a su valor normal. Todos los hallazgos anteriores proporcionan una aproximación a pautas concisas y bien justificadas para el desarrollo del protocolo de re entrada.

Issus de l'effondrement gravitationnel des fluctuations de matière primordiales, les amas de galaxies sont constitués d'un halo de matière noire, d'un plasma de baryon ou « gaz chaud » et de galaxies. Le comptage des amas apporte des contraintes fortes sur la cosmologie.Mon travail consiste à améliorer la détection de la composante de gaz chaud des amas, à la fois pour des structures proches et lointaines. Ce gaz chaud est détectable dans les cartes du satellite Planck par effet Sunyaev-Zel'dovich et dans les cartes du satellite ROSAT par rayonnement de freinage.La première partie de cette thèse consiste à détecter du gaz chaud dans les cartes de Planck à la position des quasars de l'expérience BOSS, donc dans des structures lointaines.Le signal est dominé par une émission de type poussière. J'ai donc élaboré un filtre capable d'extraire un signal de gaz chaud sous-dominant et de le séparer de l'émission de poussière. Le signal de gaz chaud obtenu par cette approche est significatif pour les structures à redshift z >2.5.La seconde partie de cette thèse, la détection simultanée, est dédiée à la construction d'un filtre capable d'extraire des amas (à z<1.5) individuellement dans les données ROSAT et adapté à la statistique du bruit. Ce filtre est en outre conçu dans la perspective d'être combiné avec le filtre utilisé pour détecter les amas dans les données Planck. L'objectif final étant d'obtenir plus d'amas moins massifs
Originating from the gravitational collapse of the primordial fluctuations of matter, galaxy clusters are the mixture of a dark matter halo, a baryonic plasma also called « hot gas » and several galaxies. Cluster counts provide stringent constraints on cosmology.Improving the detection of the hot gas component in nearby or distant structures is the main goal of my work. We can detect this hot gas in the Planck satellite maps thanks to the Sunyaev-Zel'dovich effect and in the ROSAT satellite maps by bremsstrahlung.The first part of my thesis is dedicated to the detection of hot gas in Planck maps at the positions of BOSS quasars, so in distant structures.Dust-like emission dominates our signal. I developped a new filter in order to separate the possible sub-dominant hot gas emision from the dust one. I get a significnt hot gas signal for structures with redshift z >2.5.In the second part of the thesis, the simultaneous detection, I build a filter suited for extracting clusters (z<1.5) individually in the ROSAT data respecting the noise statitistics. This filter is also designed to be combined with the filter used for detecting clusters in Planck maps. Increasing the number of less massive clusters will be the final goal

Orientador: George Luiz Luvizotto
Resumo: A formação das rias fluviais na Amazônia possui uma relação bem conhecida com o processo de avanço do nível do mar durante o Holoceno. Sugestões sobre a presença de controle estrutural e tectônico na gênese destas e de outros elementos do relevo amazônico tem sido levantadas por diversos autores, porém poucos elementos conclusivos foram apresentados até o momento. Este trabalho apresenta, no primeiro momento, uma série de evidências de diferentes fontes mostrando controle estrutural ao longo do ria do Tapajós e em áreas de terra firme adjacentes. A metodologia utilizada, é inovadora por integrar dados geomorfológicos, geológicos e geofísicos (sísmica, magnetometria e gravimetria) obtidos sem custo e disponíveis para grandes áreas, o que é uma grande vantagem em uma zona de difícil acesso como a Amazônia. Trata-se ainda de uma abordagem pouco usual dentro da geomorfologia na qual encontramos resultados muito promissores. Os resultados mostram a influência de elementos estruturais na configuração do relevo amazônico na região do baixo Tapajós. É proposto um modelo de horsts e grábens limitados por lineamentos com direção ENE-WSW com expressão regional. Em seguida apresentamos uma classificação para o canal do Tapajós baseado em variáveis morfométricas extraídas de perfil transversal. A classificação apresenta três trechos distintos para o canal do Tapajós no perímetro analisado, denominados Trecho do Canal Estreito, Baixo Trecho da Ria e Alto Trecho da Ria. Estes trechos possue... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The formation of the fluvial rias in the Amazon has a well-known relationship with the process of sea level transgression during the Holocene. Suggestions about the presence of structural and tectonic control in the genesis of these and other elements of the Amazonian relief have been raised by several authors, but few conclusive elements have been presented so far. This work presents, in the first moment, a series of evidences from different sources showing structural control along the Tapajós Ria and in adjacent land areas. The methodology used is innovative because it integrates geomorphological, geological and geophysical data (seismic, magnetometry and gravimetry) obtained at no cost and available for large areas, which is a great advantage in an area of difficult access such as the Amazon. It is also an unusual approach within geomorphology in which we find very promising results. The results show the influence of structural elements in the configuration of the Amazonian relief in the region of the lower Tapajós. A model of horsts and grabens limited by lineaments with regional expression is proposed. Next, we present a classification for the Tapajós channel based on morphometric variables extracted from transversal profiles. The classification presents three distinct sections for the Tapajós channel in the analyzed perimeter, here called Narrower Channel Reach, Lower Ria Reach and Higher Ria Reach. These reaches have statistical support and agreement with most of the s... (Complete abstract click electronic access below)
Doutor

Cette thèse se focalise sur l'étude des amas de galaxies, via l'effet Sunyaev-Zel'dovich (tSZ), qui consiste en l'interaction de ces même amas avec le fond diffus cosmologique. Pour ce faire j'ai utilisé les données expérimentale de l'instrument HFI du satellite PLANCK. Cette thèse ce découpe en trois parties majeures, (1) L'analyse et le traitement des données en temps, des données brut jusqu'au cartes du ciel, ce focalisant tout particulièrement sur les effets systématiques. (2) Le développement de méthode de séparation de sources, permettant la construction de cartes par émission astrophysique (tout particulièrement l'effet Sunyaev-Zel-dovich) à partir de données multi-fréquences. (3) L'analyse physique des cartes d'effet Sunyaev-Zel'dovich, produit par le gaz d'électron chaud présent dans les amas de galaxies. Ce travail permet la mise en place de contrainte, sur le profile de pression des amas de galaxies, sur la présence de filaments de matière entre des système binaire d'amas de galaxies, ainsi que la mise en évidence du spectre de puissance de l'effet tSZ.

Les galaxies sont des phares dans l'Univers qui nous permettent de comprendre l'évolution de la répartition dans l'Univers de la matière sous toutes ses formes. L'étude de ces galaxies à différentes époques permet de comprendre comment elles s'organisent à grande échelle (supérieures à la distance inter-galaxies) mais aussi comment elles se forment, et forment leurs étoiles.À notre époque cosmologique, les galaxies dans les environnements les plus denses (amas, groupes) présentent des propriétés bien différentes des galaxies dans les environnements moins denses. Cette bimodalité entre 1) des galaxies elliptiques, massives, vieilles et formant peu d'étoiles dans les environnements denses d'une part, et 2) des galaxies spirales, plus jeunes et en phase de formation stellaire intenses dans les environnements moins denses d'autre part, traduit des mécanismes d'évolution et de formation différents.L'étude des galaxies dans les amas révèle des indices "fossiles" sur une époque de dernière phase significative de formation stellaire à un redshift z~2, et pointe vers un épisode de formation stellaire synchrone dans les galaxies de l'amas, et dans de colossales proportions (~500 Masses solaires par an, à mettre en regard avec les taux de formation stellaire moyens observés dans l'Univers local de l'ordre de ~1-10 Masses solaires par an). Mais cette phase manque toujours d'une conclusion observationnelle directe, même si de récentes observations vont dans ce sens.Une voie possible pour la recherche des ces objets est de chercher à détecter leur émission dans l'infrarouge lointain, qui trace directement la formation stellaire. C'est ce qui a été réalisé à l'aide du satellite Planck. Des données Planck/HFI, une équipe en collaboration avec la notre a extrait 2151 candidats amas en phase de formation stellaire intense. Un suivi sur 228 candidats a été réalisé avec le télescope spatial Herschel/SPIRE, et a révélé des surdensités de sources rouges, compatible avec une distribution en redshift autour de z~2, et des taux de formation stellaire de l'ordre de 700 masses solaires par an.Pour mieux contraindre le redshift de ces candidats, et étudier leur contenu en étoiles, un autre suivi sur 80 candidats a été réalisé à l'aide de l'instrument IRAC sur le télescope spatial Spitzer. Mon travail porte principalement sur le traitement et l'analyse de ces données.Les longueurs d'onde de l'instrument IRAC (3.6 et 4.5 microns) sont en effet parfaitement adaptées pour détecter un pic caractéristique d'émission des populations stellaires, permettant une estimation du redshift et de la masse stellaire.Mon travail a révélé des surdensités de sources IRAC rouges (z>1.3) aux positions des sources SPIRE rouges (z~2, SFR~700Msol.an), compatibles avec des amas ou proto-amas en formation stellaire intense. Des estimations de redshifts photométriques et de masse stellaire montrent que ces objets sont compatibles avec les progéniteurs des amas locaux.Ces candidats nécessitent cependant une confirmation, notamment à l'aide de l'obtention de redshifts spectroscopiques. Ce travail a déjà commencé, et deux candidat ont déjà été confirmés à des redshifts de 2.15 et 2.36 à l'aide du 30m/IRAM. Des données obtenues avec les interféromètres ALMA et NOEMA ont révélé que l'émission SPIRE était dans certains cas originaires de plusieurs galaxies.Ces premiers résultats sont encourageants, mais une étude à d'autres longueurs d'onde (proche infrarouge) est aussi nécessaire pour mieux contraindre le contenu en masse de nos objets, ainsi que leur histoire de formation stellaire. Les données sont en parties déjà disponibles, et leur analyse a déjà commencé
Galaxies are beacons in the Universe that allow us to understand the evolution of the distribution matter in all its forms. The study of galaxies at different epochs helps to understand how they organize at large scales (greater than inter-galaxies distance) but also how they formed, and formed their stars.At our cosmic epoch, galaxies that reside in the densest environments (clusters, groups) have very different properties compared to galaxies residing in less dense environments. This bimodality between 1) elliptical galaxies, massive, old and forming little stars in dense environments on the one hand, and 2) of spiral galaxies, younger and experimenting intense star formation in less dense environments indicates different evolutionary mechanisms and formation mechanisms.The study of galaxies in clusters reveals that they probably experimented intense star formation at redshifts z ~ 2, and points to a synchronous episode of star formation in the galaxies in the cluster, and of colossal proportions (~ 500 solar masses per year, to be compared with the average rate of star formation observed in the local Universe in the order of ~ 1-10 solar masses per year). But this phase still lack a direct observational conclusion, although recent observations in this direction.One possible way to search for these objects is to try to detect their emission in the far infrared, which traces directly star formation. This is what has been achieved with the Planck satellite. From Planck / HFI data, a team in collaboration with us extracted 2151 cluster candidates experimenting an intense star formation phase. A follow-up of 228 candidates was made with the space telescope Herschel / SPIRE, and revealed overdensities of red sources, compatible with a redshift distribution peaking around z ~ 2, and star formation rates of approximately 700 masses solar year.To better constrain the redshift of these candidates, study their contents in terms of stars, another follow-up on 80 candidates was conducted using the IRAC instrument on the Spitzer Space Telescope. My work focuses on the analysis and interpretation of such data.The wavelengths of the IRAC instrument (3.6 and 4.5 microns) are indeed tailored to detect a characteristic peak emission of stellar populations, to estimate the redshift and the stellar mass.My work revealed overdensities of red IRAC sources (z> 1.3) at the positions of the red SPIRE sources (z ~ 2 ~ 700Msol.an SFR), compatible with clusters or proto-clusters in an intense star formation phase. Estimates of photometric redshifts and stellar mass show that these objects are compatible with the progenitors of local clusters.These candidates, however, require confirmation, especially with obtaining spectroscopic redshifts. This work has already begun, and two candidates have already been confirmed at redshifts of 2.15 and 2.36 using the 30m / IRAM. Data obtained with the ALMA interferometer and NOEMA revealed that the SPIRE emission originates in some cases from several galaxies.These initial results are encouraging, but a study at other wavelengths (near infrared) is also needed to better constrain the content of our mass objects, and their star formation history. The data is already available on part of the smple, and analysis has begun

Galaxy clusters, the massive systems host hundreds of galaxies, are invaluable cosmological probes and astrophysical laboratories. Besides these fascinating galaxies, the concentration of dark matter creates a deep gravitational potential well, where even light passing by is bended and the background image is distorted. The baryonic gas falling into the potential well is heated up to more than 10^7 K that free electrons start to emitting in X-ray. Observing those phenomena leads to a throughout understanding of gravity, particle physics and hydrodynamics. In addition, residing on the top of the density perturbations, clusters are sensitive to the initial condition of the Universe, such that they are complimentary tools for cosmology studies. In this thesis we first introduce the basic framework of the Universe and supporting observational evidence. Following that, we sketch the principle to use clusters for cosmology study via their redshift and mass distribution. However cluster mass is not a direct observable, so we need to estimate it by other channels. We briefly exhibit cluster observations in optical, X-ray and microwave bands and discuss the challenges in estimating the underlying cluster mass with them. After this introduction, we present our results on three aspects of the cluster cosmology study. First, we present a study of Planck Sunyaev-Zel’dovich effect (SZE) selected galaxy cluster candidates using Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) imaging data. To fulfil the strength of SZE survey, the redshifts of clusters are required. In this work we examine 237 Planck cluster candidates that have no redshift in the Planck source catalogue. Among them, we confirmed 60 galaxy clusters and measure their redshifts. For the remaining sample, 83 candidates are so heavily contaminated by stars due to their location near the Galactic plane that we do not identify galaxy members and assign reliable redshifts. For the rest 94 candidates we find no optical counterparts. By examining with 150 Planck confirmed clusters with spectroscopy redshifts, our redshift estimations have an accuracy of σ_{z/(1+z)}~0.022. Scaling for the already published Planck sample, we expect the majority of the unconfirmed candidates to be noise fluctuations, except a few at high redshift that the Pan-STARRS1 (PS1) data are not sufficiently deep for confirmation. Thus we use the depth of the optical imaging for each candidate together with a model of the expected galaxy population for a massive cluster to estimate a redshift lower limit, beyond which we would not have expected to detect the optical counterpart. Second, we use 95GHz, 150GHz, and 220GHz observations from South Pole Telescope (SPT) to study the SZE signatures of a sample of 46 X-ray selected groups and clusters drawn from ~6 deg^2 of the XMM-Newton Blanco Cosmology Survey (XMM-BCS). The wide redshift range and low masses make this analysis complementary to previous studies. We develop an analysis tool that using X-ray luminosity as a mass proxy to extract selection-bias corrected constraints on the SZE significance- and Y_{SZ}-mass relations. The SZE significance- mass relation is in good agreement with an extrapolation of the relation obtained from high mass clusters. However, the fit to the Y_{SZ}-mass relation at low masses, while in agreement with the extrapolation from high mass SPT sample, is in tension at 2.8σ with the constraints from the Planck sample. We examine the tension with the Planck relation, discussing sample differences and biases that could contribute. We also analyse the radio galaxy point source population in this ensemble of X-ray selected systems. We find 18 of our systems have 1 GHz Sydney University Molonglo Sky Survey (SUMSS) sources within 2 arcmin of the X-ray centre, and three of these are also detected at significance >4 by SPT. Among these three, two are associated with the brightest cluster galaxies, and the third is a likely unassociated quasar candidate. We examined the impact of these point sources on our SZE scaling relation result and find no evidence of biases. We also examined the impact of dusty galaxies. By stacking the 220 GHz data, we found 2.8σ significant evidence of flux excess, which would correspond to an average underestimate of the SZE signal that is (17±9) % in this sample of low mass systems. Finally we predict a factor of four to five improvements on these SZE mass-observable relation constraints based on future data from SPTpol and XMM-XXL. In the end we present a study using clusters as tools to probe deviations from adiabatic evolution of the Cosmic Microwave Background (CMB) temperature. The expected adiabatic evolution is a key prediction of standard cosmology. We measure the deviation of the form T(z)=T_0(1+z)^{1-α} using measurements of the spectrum of the SZE with SPT. We present a method using the ratio of the SZE signal measured at 95 and 150 GHz in the SPT data to constrain the temperature of the CMB. We validate that this approach provides unbiased results using mock observations of cluster from a new set of hydrodynamical simulations. Applying this method to a sample of 158 SPT-selected clusters, we measure α=0.017^{+0.030}_{−0.028} consistent with the standard model prediction of α=0. Combining with other published results, we find α=0.005±0.012, an improvement of ~ 10% over published constraints. This measurement also provides a strong constraint on the effective equation of state, w_{eff}=−0.994±0.010, which is presented in models of decaying dark energy.

La mesure de la distribution de matière dans l'Univers offre une sonde importante pour la cosmologie. Elle peut être tracée à différentes étapes de la formation des structures en utilisant l'analyse des anisotropies primaires et secondaires du fond diffus cosmologique (CMB). Cette thèse se focalise sur l'analyse des données du satellite Planck et celles de la caméra NIKA installée au sol au télescope de 30 mètres de l'IRAM.La première partie introduit le contexte, en se concentrant sur: 1) l'inflation, qui procure une origine naturelle aux fluctuations de matière observées dans l'Univers; 2) la réionisation, qui correspond au moment où les premières étoiles se forment; 3) les amas de galaxies, qui sont les briques de l'Univers plus récent.La seconde partie se concentre sur la réduction des données de NIKA. Le développement de la chaîne d'analyse, qui permet de passer des données brutes aux cartes astrophysiques, est présenté. Elle est dédiée aux détecteurs à inductance cinétique, nouvellement développés pour la caméra NIKA. Les outils et les simulations utilisés pour caractériser les cartes sont aussi présentés.La troisième partie est dédiée à l'observation et l'analyse des amas de galaxies par effet Sunyaev-Zel'dovich (SZ), i.e. l'interaction Compton inverse entre les photons du CMB et les électrons énergétiques dans les amas. Une fois obtenues, les cartes SZ sont combinées avec des données X afin de mesurer les propriétés thermodynamiques et de matière des amas observés. Les résultats principaux sont: la première observation de l'effet SZ avec des détecteurs à inductance cinétique, la mesure du profil de pression dans un amas à haut redshift (z=0.89), l'étude de la contamination par les sources ponctuelles dans un amas résolu, et la cartographie SZ dans un amas en collision triple.La dernière partie présente l'analyse des données de Planck en polarisation. Les effets systématiques aux grandes échelles angulaires et les outils développés pour les identifier et les corriger y sont discutés. Les données en polarisation aux grandes échelles permettent à la fois de chercher les empreintes des fluctuations quantiques générées pendant l'inflation et de mesurer la réionisation
The measurement of the matter distribution in the Universe provides valuable tests for cosmology. It can be traced at various steps of the formation of structures using the analysis of the primary and secondary anisotropies in the Cosmic Microwave Background (CMB). This thesis focuses on the data analysis of the observations of the Planck satellite and that of the ground-based camera NIKA installed at the IRAM-30m telescope.The first part introduces the context, focussing on: 1) the inflation, which provides a natural origin for the matter fluctuations seen in the Universe; 2) the reionization, which corresponds to the moment when the first stars form; 3) clusters of galaxy, that are the building blocks of the more recent Universe.The second part focuses on the data reduction of the NIKA data. The development of the data reduction pipeline, allowing to go from raw data to maps, is presented. It is dedicated for the newly developed kinetic inductance detectors used by NIKA. Tools and simulations are also constructed to characterize the maps.The third part is dedicated to the observation and the analysis of galaxy clusters through the Sunyaev-Zel'dovich (SZ) effect, i.e. the inverse Compton interaction of CMB photons and free electrons in clusters. Once recovered, the SZ maps are combined to X-ray data to measure the matter content and thermodynamic properties of the observed clusters. The main results are: the first observation of the SZ effect with kinetic inductance detectors, the measurement of the pressure profile of a high redshift cluster ($z=0.89$), the study of point source contamination in a resolved cluster, and the SZ mapping in a triple merger.The last part is dedicated to the analysis of Planck polarization data. In particular, we discuss large angular scale systematics and the tools developed to identify and correct for them. The large scales CMB polarization data allows both to search for the imprint of the quantum fluctuations generated during inflation, and to measure the reionization

Lo scopo di questa tesi è la trattazione della materia oscura partendo dalle evidenze sperimentali, ripercorrendo i possibili costituenti e riportando dati relativi a rivelazioni dirette ed indirette. Il primo capitolo è dedicato alla discussione delle due più importanti evidenze della presenza di materia oscura, ossia le curve di rotazione ed il Bullet Cluster, che risultano entrambe interazioni di tipo gravitazionale. Si provvede inoltre a fornire le due più plausibili soluzioni in grado di spiegare i risultati ottenuti dalle osservazioni sperimentali e a discutere la loro validità come modello per la descrizione di tali fenomeni. Il capitolo successivo è volto all'esposizione delle possibili particelle che compongono la materia oscura, discutendo quali siano le più probabili, e alla spiegazione della loro creazione nell'Universo primordiale. La terza parte è dedicata alle rilevazioni dirette, consistenti nello scattering fra particelle di materia oscura e nuclei, ed in particolare all'analisi del modello dei neutralini. Vengono poi riportati nello stesso capitolo i risultati di tali rilevazioni, con riferimento agli esperimenti CDMS II, XENON100 e LUX. Nel quarto capitolo si tratteranno i risultati delle rilevazioni indirette, ossia osservazioni di processi derivanti dall'annichilazione di materia oscura, e verranno riportati i risultati degli esperimenti più importanti, fra cui i più recenti sono Fermi-LAT e CTA (ancora in sviluppo). L'ultimo paragrafo è riservato ad un breve riassunto dei risultati e delle ipotesi trattate, per raccogliere i dati più importanti e fornire una visione generale della materia oscura.

Les travaux effectués dans cette thèse concernent les cellules photovoltaïques fabriquées à partir de matériaux organiques discotiques. Ces derniers possèdent de bonnes propriétés de transport de charges et d'excitons lorsque les matériaux impliqués sont ordonnés sous forme de colonnes. Une stratégie est proposée et étudiée pour améliorer les paramètres de ces dispositifs organiques. En particulier, des investigations ont été menés sur la structuration des matériaux en solution et en films minces. En divers solvants organiques, l'agrégation des molécules discotiques en colonnes d'une taille de quelques nanomètres a été mis en évidence, avec un empilement dense des disques dans la colonne et sans ordre intercolonnaire dépassant les voisins directs. Par diffraction des rayons X en incidence rasante, la structure des films minces a été exploré. Les résultats soulignent l'indispensable nécessité d'orienter les films de cristaux liquides colonnaires.

In this dissertation, sparse processing of signals for directions-of-arrival (DoAs) estimation is addressed in the framework of Compressive Sensing (CS). In particular, DoAs estimation problem for different types of sources, systems, and applications are formulated in the CS paradigm. In addition, the fundamental conditions related to the ``Sparsity'' and ``Linearity'' are carefully exploited in order to apply confidently the CS-based methodologies. Moreover, innovative strategies for various systems and applications are developed, validated numerically, and analyzed extensively for different scenarios including signal to noise ratio (SNR), mutual coupling, and polarization loss. The more realistic data from electromagnetic (EM) simulators are often considered for various analysis to validate the potentialities of the proposed approaches. The performances of the proposed estimators are analyzed in terms of standard root-mean-square error (RMSE) with respect to different degrees-of-freedom (DoFs) of DoAs estimation problem including number of elements, number of signals, and signal properties. The outcomes reported in this thesis suggest that the proposed estimators are computationally efficient (i.e., appropriate for real time estimations), robust (i.e., appropriate for different heterogeneous scenarios), and versatile (i.e., easily adaptable for different systems).

This thesis generalizes and interprets Kesten\''s Incipient Infinite Cluster (IIC) measure in two ways. Firstly we generalize Járai\''s result which states that for planar lattices the local configurations around a typical point taken from crossing collection is described by IIC measure. We prove in Chapter 2 that for backbone, lowest crossing and set of pivotals, the same hold true with multiple armed IIC measures. We develop certain tools, namely Russo Seymour Welsh theorem and a strong variant of quasi-multiplicativity for critical percolation on 2-dimensional slabs in Chapters 3 and 4 respectively. This enables us to first show existence of IIC in Kesten\''s sense on slabs in Chapter 4 and prove that this measure can be interpreted as the local picture around a point of crossing collection in Chapter 5.

Herein, a series of tin and oxidovanadium complexes, as well as a hexanuclear manganese cluster, supported by the bidentate, dianionic perfluoropinacolate (pinF) ligand, {(O(C(CF3)2)2}2−, are reported. While six-coordinate SnIV-pinF complexes (2.1−2.3) were found to be spectroscopically similar to SnO2 (cassiterite), four-coordinate SnII-pinF complexes (2.4−2.5) possess low 119Sn NMR chemical shifts and remarkably high quadrupolar splitting. Additionally, the Sn(II) complexes are unusually unreactive towards both Lewis acids and bases. Computational analysis suggests that this lack of reactivity with Lewis acids arises from the energetic inaccessibility of the HOMO (5s), and the lack of reactivity with Lewis bases is due to donation into the LUMO (5px) by fluorine atoms on the ligand. Furthermore, monomeric and dimeric {VIV=O}- and {VV=O}-pinF complexes (3.1−3.4) were synthesized and characterized, including (Me4N)2[V2(O)2(μ-O)2(pinF)2] (3.3a). Complex 3.3a was found to catalyze the oxidation of several benzyl alcohols at room-temperature under ambient conditions, reproducing reactivity known for VOx surfaces and demonstrating the thermodynamically challenging selective oxidation of alcohols to aldehydes/ketones. Finally, a hexanuclear manganese cluster, {MnIII4MnIV2(pinF)6(OK(THF))4(OH)4}, abbreviated {Mn6} (4.1) which contains four-fold axial symmetry, and its oxidized analog {MnIII3MnIV3(pinF)6(OK(THF))4(OH)4}[PF6] (4.2), were prepared and characterized. High-field EPR measurements of 4.1 confirm a high spin magnetic ground state of ST = 11, corroborating the oxidation state assignments of the manganese centers. While EPR and CTM data suggest the possibility of slow magnetic relaxation for 4.1, field-dependent SQUID magnetometry reveals a lack of magnetic hysteresis, precluding the SMM behavior hypothesized for 4.1.

Numerical models for globular cluster evolution using the orbit-averaged Fokker-Planck equation are compared with observations of the globular clusters M71 and NGC 6397. The first set of models studied includes a mass spectrum, a tidal boundary and allows for a central energy source from the formation, hardening and destruction of binaries formed in three-body interactions. These models are compared to star-count mass functions and surface density profiles for M71. It is possible to reproduce the tidal boundary and degree of mass segregation using these models but the central density profiles of the fitted models are much steeper than is observed. On the basis of the degree of mass segregation and the short relaxation time, M71 is dynamically a highly evolved object, but the surface density profile contradicts this. Several modifications of the model are considered to resolve this difficulty, and an additional energy source, which does not require extreme densities to operate, appears to be required. New observations of the cluster NGC 6397 are presented. This cluster is presently at a similar position in the galaxy as M71, and has a similar mass and mass function, but is much more centrally concentrated. NGC 6397 is a low metallicity cluster with halo kinematics, in contrast to the metal-rich disk cluster M71. The observations have been reduced to give a surface density profile, and mass functions at two distances from the cluster centre. The surface density profile is fit by a power-law with slope —0.8 in the central arc minute. The mass functions give some evidence for mass segregation, but the low signal-to-noise of the outer mass function limits the significance of this observation. A second set of models, augmented to include the effects of mass loss due to stellar evolution, are used to find matches for the observations of M71 and NGC 6397. A diagram showing the evolution with time of the amount of mass segregation and the half-density radius is shown to be useful in identifying good candidate models. Stellar evolution appears not to solve the problem ofM71 as no satisfactorily matching model has been found. Possible solutions to this problem are discussed. The observations of NGC 6397 can be reproduced by the models and the best such model is described. This model has an initial mass function with a Salpeter-like slope and is undergoing core-collapse. This demonstrates that a numerical model based on the orbit-averaged Fokker-Planck equation, and including an evolving mass spectrum, a tidal boundary and the binary energy source, is a useful model for the dynamical evolution of some globular clusters.

In this dissertation, we present three complementary studies of the processes that drive planetary migration. The first is a radial-velocity survey in search of giant planets in adolescent (<1 >Gyr) open clusters. While several different mechanisms may act to drive giant planets inward, only some mechanisms will excite high eccentricities while doing so. Measuring the eccentricities of young hot Jupiters in these clusters (at a time before the orbits have had a chance to circularize due to tidal friction with their host stars) will allow us to identify which mechanisms are most important. Through this survey, we detect the first 3 hot Jupiters in open clusters (and at least 4 long-period planets), and we measure the occurrence rate of hot Jupiters in clusters to be similar to that of the field (~1%). We determine via analyses of hot Jupiter eccentricities and outer companions in these systems that high eccentricity migration mechanisms (those requiring the presence of a third body) are important for migration. The second project, an adaptive optics imaging survey for stellar companions to known hot Jupiter hosts, aims to determine the role that stellar companions in particular play in giant planet migration. Through a preliminary analysis, we derive a lower limit on the binary frequency of 45% (greater than that of the typical field star), and we find that the presence of a companion is correlated with misalignment of the spin-orbit angle of the planetary system, as would be expected for stellar Kozai-Lidov migration: at least 74% of misaligned systems reside in binaries. We thus conclude that among high eccentricity migration mechanisms, those requiring a stellar companion play a significant role. Finally, we describe simulations of measurements of the planet population expected to be discovered by TESS, and use these to demonstrate that a strong constraint on the obliquity distribution of small planets can be derived using only TESS photometry, Gaia astrometry, and vsin(i) measurements of the host stars. This obliquity distribution will be a key piece of evidence to help detemine the likely formation and migration histories of small planets, and can contribute to the assessment of the potential for Earth-like planets to harbor life.