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Machado, murtinheiras martins Andre. "Statistical analysis of large scale surveys for constraining the Galaxy evolution". Thesis, Besançon, 2014. http://www.theses.fr/2014BESA2026/document.
Pełny tekst źródłaThe formation and evolution of the thick disc of the Milky Way remain controversial. We made use of a population synthesis model of the Galaxy, the Besançon Galaxy Model (Robin et al. 2003), which can be used for data interpretation, study the Galactic structure and test different scenarios of Galaxy formation and evolution. We examined these questions by studying the shape and the metallicity distribution of the thin and thick disc using the population synthesis approach. We imposed on simulations observational errors and biases to make them directly comparable to observations. We corrected magnitudes and colors of stars, from the simulation, using an extinction model. The available extinction models do not always reproduce the exact quantity of extinction along the line of sight. A code to correct the distribution of extinction in distance along these lines have been developed and the corrected extinctions have been applied on model simulations. We studied the shape of the thin disc using photometric data at low latitudes from the SDSS-SEGUE survey. We compared qualitatively and quantitatively observations and simulations and try to constrain the Initial Mass Function. Using the spectroscopic survey SEGUE we selected Main Sequence Turnoff (MSTO) stars (Cheng et al 2012) and K giants to study the metallicity distribution of the thin and thick discs. We computed a distance for each star from the relation between effective temperatures and absolute magnitudes for the observed and simulated catalogs. These two catalogues have the same biases in distances, therefore are comparable. We developed a tool based on a MCMC-ABC method to determine the metallicity distribution and study the correlations between the fitted parameters. We confirmed a radial metallicity gradient of -0.079 ± 0.015 dex kpc−1 for the thin disc. We obtained a solar neighborhood metallicity of the thick disc of -0.47 ± 0.03 dex similar to previous studies and the thick disc shows no gradient but the data are compatible with an inner positive gradient followed by a outer negative one. Furthermore, we have applied the developed tools to the Gaia-ESO spectroscopic survey and computed the metallicity distribution of F/G/K stars in the thin and thick disc assuming a two epoch formation for the thick disc of the Milky Way. We obtained a local metallicity in the thick disc of -0.23 ± 0.04 dex slightly higher than the one obtained with SEGUE but in agreement with Adibekyan et al. (2013) and a radial metallicity gradient for the thick disc in agreement with our previous analysis of SEGUE data and the literature. The local metallicity is in fair agreement with literature at the 3σ level but because the GES data is an internal release under testing further analysis with more data and better calibrations have to be done. The existence of a flat gradient in the thick disc can be a consequence of an early formation from a highly turbulent homogeneous well mixed gas, unless it has suffered heavy radial mixing later on
Cole, Shaun. "Evolution of large scale structure and galaxy formation". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315745.
Pełny tekst źródłaMajewski, Steven R., Ricardo P. Schiavon, Peter M. Frinchaboy, Carlos Allende Prieto, Robert Barkhouser, Dmitry Bizyaev, Basil Blank i in. "The Apache Point Observatory Galactic Evolution Experiment (APOGEE)". IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/625493.
Pełny tekst źródłaDurkalec, Anna. "Properties and evolution of galaxy clustering at 2". Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4758/document.
Pełny tekst źródłaThis thesis focuses on the study of the properties and evolution of galaxy clustering for galaxies in the redshift range 22. I was able to measure the spatial distribution of a general galaxy population at redshift z~3 for the first time with a high accuracy. I quantified the galaxy clustering by estimating and modelling the projected (real-space) two-point correlation function, for a general population of 3022 galaxies. I extended the clustering measurements to the luminosity and stellar mass-selected sub-samples. My results show that the clustering strength of the general galaxy population does not change significantly from redshift z~3.5 to z~2.5, but in both redshift ranges more luminous and more massive galaxies are more clustered than less luminous (massive) ones. Using the halo occupation distribution (HOD) formalism I measured an average host halo mass at redshift z~3 significantly lower than the observed average halo masses at low redshift. I concluded that the observed star-forming population of galaxies at z~3 might have evolved into the massive and bright (Mr<-21.5) galaxy population at redshift z=0. Also, I interpret clustering measurements in terms of a linear large-scale galaxy bias. I find it to be significantly higher than the bias of intermediate and low redshift galaxies. Finally, I computed the stellar-to-halo mass ratio (SHMR) and the integrated star formation efficiency (ISFE) to study the efficiency of star formation and stellar mass assembly. I find that the integrated star formation efficiency is quite high at ~16% for the average galaxies at z~3
Legrand, Louis. "Large surveys : from galaxy evolution to cosmological probes". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASP023.
Pełny tekst źródłaLarge galaxy surveys are like open windows on our Universe: they provide precious insights on its components and on its evolution. On the one hand, pencil surveys go deep into the cosmos to explore the formation and evolution of galaxies. On the other hand, wide surveys are mapping the distribution of matter on large scales to understand the nature of dark energy and dark matter.During my thesis, I explore the capabilities of these large surveys to address the following questions:1. What are the main drivers of galaxy evolution? 2. What improvements on our knowledge of the Universe will be brought by upcoming wide galaxy surveys? Using precise galaxy stellar-mass function measurements in the COSMOS field, I first determine the stellar-to-halo mass relation through a parametric abundance matching technique. Thanks to the completeness of the COSMOS survey from z ~ 0.2 to z ~ 5, I obtain for the first time this relation over such a large redshift range from a single coherent sample.I find that the ratio of stellar-to-halo mass content peaks at a characteristic halo mass which increases up to z = 2.3 and remains flat up to z = 4.This steady increase of the characteristic halo mass questions the role of cold gas inflows as drivers of galaxy formation at high redshift.To address this question, I link observations of the cold molecular gas content in galaxies up to z = 4 to the evolution of the dark matter halo mass. I find that the joint evolution of cold gas mass fraction and halo mass is in agreement with the hypothesis of cold gas inflows being responsible of efficient galaxy formation at high redshift.With the scope of maximising the cosmological power of next generation spectroscopic surveys, I show that a novel cosmological observable, the angular redshift fluctuations (ARF) will provide complementary cosmological information in addition to the standard angular galaxy clustering. Due to its distinct sensitivity to the peculiar velocity field, I find that the cosmological and galaxy bias parameters express different degeneracies when inferred from ARF or from angular galaxy clustering.As such, combining both observables breaks these degeneracies and greatly decreases the marginalised uncertainties, by a factor of at least two on most parameters in the ^CDM and wCDM models.As part of the Euclid collaboration, I then investigate the cosmological power of the upcoming Euclid survey, which will offer us an exquisite measurement of the matter distributions on the full extra-galactic sky.In order to fully exploit all the potential of the Euclid survey it is crucial to combine it with upcoming CMB surveys.I use the Fisher formalism to forecast the benefits of performing a joint analysis of CMB probes with Euclid main probes (weak lensing and galaxy clustering). I test both the standard cosmological model, ^CDM, and its extensions, and show that CMB will improve the constraints by a factor two on most cosmological parameters, and most notably on dark energy modified models which are of key interest for Euclid
Hatzidimitriou, D. "The evolution and geometry of the oouter parts of the Small Magellanic Cloud". Thesis, University of Edinburgh, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234097.
Pełny tekst źródłaLaporte, Chervin F. P., Facundo A. Gómez, Gurtina Besla, Kathryn V. Johnston i Nicolas Garavito-Camargo. "Response of the Milky Way's disc to the Large Magellanic Cloud in a first infall scenario". OXFORD UNIV PRESS, 2018. http://hdl.handle.net/10150/626276.
Pełny tekst źródłaKruk, Sandor J. "Evolution of barred galaxies and associated structures". Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:34cc9283-a386-464f-b9ae-1d4e3b4fdf77.
Pełny tekst źródłaLaigle, Clotilde. "Observational and theoretical constraints on galaxy evolution at high redshift". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066343.
Pełny tekst źródłaI present in this thesis new constraints on galaxy formation and evolution while studying the galaxy mass growth and the co-evolution of the cosmic web and the embedded galaxies, from the epoch of cosmic dawn to today.To do so, I first created a new photometric catalog on the COSMOS field with precise photometric redshifts allowing to probe accurately the high-redshift Universe. I analyze this survey while relying heavily on comparisons with virtual galaxy surveys produced from state-of-the- art cosmological hydrodynamical simulations, which capture all our current knowledge of galaxy formation and evolution.From this comparative analysis, in the first part of my thesis I show that the redshift evolution of galaxy properties is reasonably well understood when invoking mass-dependent processes (AGN and stellar feed- back). I highlight also the effect of simplifying assumptions inherent to our observational methods, which bias the physical properties computed from galaxy photometry.Galaxies and haloes are embedded in the cosmic web, an intricate large-scale structure of walls, filaments and nodes. In the second part of my thesis, I show how galaxies and dark haloes gain their angular momentum from the large-scale flow, implying that some of their properties depend on their anisotropic filamentary environment. I then extract the filamentary structure from the observed photometric catalog and measure the dependence of galaxy properties to the anisotropic environment. I find mass and colour gradients towards the filaments. In turn it emerges that galaxy masses and angular momenta are two dependent quantities impacted by their anisotropic environment
Roldán, Carlos Antonio Calcáneo. "The evolution of dark matter substructure". Thesis, Durham University, 2001. http://etheses.dur.ac.uk/4232/.
Pełny tekst źródłaCzekaj, Maria A. "Galaxy evolution: A new version of the Besançon Galaxy Model constrained with Tycho data". Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/123978.
Pełny tekst źródłaLa misión Gaia (ESA, 2013) revolucionará el conocimiento sobre el origen y la evolución de nuestra Galaxia. Una óptima explotación científica de sus datos requiere disponer de modelos que permitan contrastar hipótesis y escenarios sobre estos procesos de formación. En esta tesis hemos optimizado el modelo de síntesis de poblaciones estelares de Besançon, ampliamente utilizado por la comunidad internacional, centrándonos en la componente del disco delgado. Hemos diseñado, desarrollado, implementado y testeado una nueva estructura de generación de las estrellas que permite encontrar la mejor combinación de función inicial de masa (IMF) y ritmo de formación estelar (SFR) que ajusta a las observaciones. El código permite imponer la autoconsistencia dinámica, recalculando el potencial galáctico para cada nuevo escenario de evolución. También, por primera vez, se generan sistemas binarios bajo esta consistencia dinámica, marcada por la función de luminosidad observada en el entorno solar. Esta, junto con el catálogo Tycho, han sido los dos ingredientes observacionales clave para el ajuste entre modelo y observación. También, por primera vez, hemos conseguido un ajuste aceptable a los recuentos estelares de todo el cielo hasta V=11. Se han evaluado con rigor los efectos en los recuentos estelares derivados del uso de los modelos de atmosfera, de evolución estelar y de extinción interestelar así como de parámetros tan críticos como la masa dinámica del sistema galáctico. El ajuste de estos ingredientes usando el catálogo Tycho nos ha permitido confirmar, de una vez por todas, que la SFR en el disco galáctico no ha sido constante sino decreciente desde los inicios de la formación de esta estructura. En conclusión, esta tesis proporciona un nuevo código, optimizado y flexible en el uso de los ingredientes básicos, en el que se ha realizado una rigurosa evaluación y actualización de los ingredientes que lo componen.
Kraljic, Katarina. "Links between galaxy evolution, morphology and internal physical processes". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112286/document.
Pełny tekst źródłaThis thesis aims at making the link between galaxy evolution, morphology and internal physical processes, namely star formation as the outcome of the turbulent multiphase interstellar medium, using the cosmological zoom-in simulations, simulations of isolated and merging galaxies, and the analytic model of star formation. In Chapter 1, I explain the motivation for this thesis and briefly review the necessary background related to galaxy formation and modeling with the use of numerical simulations. I first explore the evolution of the morphology of Milky-Way-mass galaxies in a suite of zoom-in cosmological simulations through the analysis of bars. I analyze the evolution of the fraction of bars with redshift, its dependence on the stellar mass and accretion history of individual galaxies. I show in particular, that the fraction of bars declines with increasing redshift, in agreement with the observations. This work also shows that the obtained results suggest that the bar formation epoch corresponds to the transition between an early "violent" phase of spiral galaxies formation at z > 1, during which they are often disturbed by major mergers or multiple minor mergers as well as violent disk instabilities, and a late "secular" phase at z < 1, when the final morphology is generally stabilized to a disk-dominated structure. This analysis is presented in Chapter 2. Because such cosmological simulations form too many stars too early compared to observed galaxy populations, I shift the focus in Chapter 3 to star formation in a sample of low-redshift galaxy simulations in isolation at parsec and sub-parsec resolution. I study the physical origin of their star formation relations and breaks and show that the surface density threshold for efficient star formation can be related to the typical density for the onset of supersonic turbulence. This result holds in merging galaxies as well, where increased compressive turbulence triggered by compressive tides during the interaction drives the merger to the regime of starbursts. An idealized analytic model for star formation relating the surface density of gas and star formation rate as a function of the presence of supersonic turbulence and the associated structure of the ISM is then presented in Chapter 4. This model predicts a break at low surface densities that is followed by a power-law regime at high densities in different systems in agreement with star formation relations of observed and simulated galaxies. The last part of this thesis is dedicated to the alternative cosmological zoom-in technique Martig et al. 2009 and its implementation in the Adaptive Mesh Refinement code RAMSES. In Chapter 5, I will present the basic features of this technique as well as some of our very first results in the context of smooth cosmological accretion
Argyle, Joshua J. "The evolution of galaxy structures from a Bayesian perspective". Thesis, University of St Andrews, 2017. http://hdl.handle.net/10023/15647.
Pełny tekst źródłaOldham, Lindsay Joanna. "The evolution of dark and luminous structure in massive early-type galaxies". Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267989.
Pełny tekst źródłaBastos, Martins Ledo Hugo Ricardo. "A census of nuclear stellar disks in early-type galaxies". Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17184.
Pełny tekst źródłaAlpaslan, Mehmet. "The cosmic web unravelled : a study of filamentary structure in the Galaxy and Mass Assembly survey". Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/4906.
Pełny tekst źródłaLee, Bomee, Mauro Giavalisco, Katherine Whitaker, Christina C. Williams, Henry C. Ferguson, Viviana Acquaviva, Anton M. Koekemoer i in. "The Intrinsic Characteristics of Galaxies on the SFR–M ∗ Plane at 1.2 < z < 4: I. The Correlation between Stellar Age, Central Density, and Position Relative to the Main Sequence". IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/627039.
Pełny tekst źródłaWicker, Raphaël. "Baryons in galaxy clusters : astrophysical effects and cosmological constraints". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASP114.
Pełny tekst źródłaGalaxy clusters are the most massive gravitationally bound structures of the universe, and the history of their formation is a direct consequence of the evolution of the large scale structure of the universe. As a result, studying these objects allows to constrain cosmological parameters, which are at the core of the models describing the evolution of our universe. The use of galaxy clusters as cosmological probes relies on the observation of their matter content, and in particular their content in ordinary matter, or "baryons". Baryonic matter is mainly present under the form of stars in galaxies and of gas inside the intra-cluster medium. However, baryons in galaxy clusters are subject to astrophysical effects which will impact their properties. These effects need to be analysed in detail in order to obtain an in depth understanding of these objects and to properly constrain the conditions that dictated their formation, their assembly, and their current properties.I propose in this thesis a thorough analysis of baryons and of their effects in clusters, from galaxies to the gas, using observations in optical, X-ray, and millimeter wavelengths. A first part of my study is focused on galaxies and the analysis of their properties from optical spectroscopy, inside two triple-cluster systems discovered by the Planck satellite. I show that these two systems appear as triple only due to projection effects on the line of sight, and that they are actually constituted of isolated clusters lying at several hundreds of megaparsecs from each other, except for a cluster pair. I show in addition that inside the most distant cluster, several galaxies are still star-forming, contrary to the galaxies in lower redshift systems. This may be the sign of a transition between a regime of high star formation in high redshift systems and the low star formation regime which is observed in low redshift clusters.The remainder of my work is dedicated to the gas fraction in galaxy clusters, in particular to constrain the bias which appears following the assumption of hydrostatic equilibrium when measuring cluster masses. This "hydrostatic bias", if poorly understood, is responsible for biased cosmological constraints from galaxy clusters. By using gas masses and total masses computed under the assumption of hydrostatic equilibrium in X-ray observations, I computed the gas fraction of 120 galaxy clusters, and constrained the value of the hydrostatic bias, as well as its evolution with mass and redshift. I show that the evolution of the bias is degenerate with cosmological parameters, leading to aberrant cosmological constraints when assuming the wrong evolution for the bias. I however show that these results are dependent on the considered sample, with trends of the bias changing depending on the mass and redshift selection of the sample. In any case, whatever the sample selection I find that my results are in agreement with a collection of other measurements of the bias using other methods, as well as with predictions from hydrodynamical simulations. These results are nevertheless in tension with the value of the bias preferred by the combination of cosmic microwave background observations with galaxy cluster number counts.Finally I combined gas fraction data of clusters with cluster number counts from millimeter wavelengths observations. This allowed me to study the constraints on cosmological parameters that this combination allowed, as well as the constraints on the hydrostatic bias. I show that adding gas fraction to cluster counts allows to break degeneracies that exist between the hydrostatic bias and cosmological parameters, without any prior on the bias.My work thus allowed to improve the understanding of the astrophysical properties of baryons in galaxy clusters. I notably highlighted some of the links and correlations between astrophysical effects and cluster cosmology, allowing for an accurate and robust description of these objects
Cousin, Morgane. "Formation & Evolution des galaxies par l'approche semi-analytique". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00968765.
Pełny tekst źródłaPelliccia, Debora. "Kinematics of COSMOS star-forming galaxies over the last eight billion years". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4733.
Pełny tekst źródłaIn the local Universe it exists a tight relation between the galaxy morphology and other physical parameters, like the galaxy internal kinematics. At higher redshift it is not clear if this relation still exists. The galaxy kinematics is one of the best tool to study the physical processes that govern the galaxy formation, by tracing the galaxy internal distributions of luminous and dark matter and their evolution with time. This thesis presents the new survey HR-COSMOS aimed to obtain the first statistical and representative sample to study the kinematics of star-forming galaxies in the treasury HST/ACS COSMOS deep field at redshift 0
Whitaker, Katherine E., Rachel Bezanson, Dokkum Pieter G. van, Marijn Franx, der Wel Arjen van, Gabriel Brammer, Natascha M. Förster-Schreiber i in. "Predicting Quiescence: The Dependence of Specific Star Formation Rate on Galaxy Size and Central Density at 0.5 < z < 2.5". IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/623862.
Pełny tekst źródłaWhitaker, Katherine E., Rachel Bezanson, Dokkum Pieter G. van, Marijn Franx, der Wel Arjen van, Gabriel Brammer, Natascha M. Foerster-Schreiber i in. "Predicting Quiescence: The Dependence of Specific Star Formation Rate on Galaxy Size and Central Density at 0.5 < z < 2.5". IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/623944.
Pełny tekst źródłaRibeiro, Bruno. "Morphology as a tracer of evolution in the early phases of galaxy assembly". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4744/document.
Pełny tekst źródłaThe global properties of galaxies show a strong evolution of the star formation rate and stellar mass density at the epoch of galaxy assembly, driven by several competing physical processes (merging, accretion, feedback, environment,...). The morphological properties of galaxies are also strongly evolving over the same timescales. I investigate how the evolution of the morphological properties is connected to the spectrophotometric properties of galaxies since z~6. The spectroscopic data obtained within the VIMOS Ultra Deep Survey (VUDS), a new unique spectroscopic survey of ~10000 galaxies between redshifts z~2 and z~6 conducted at the ESO-VLT, combined with the available Hubble Space Telescope imaging surveys such as COSMOS or CANDELS provide a great way of probing galactic evolution across this cosmic epoch.From the results that I have obtained, I conclude that the different morphological properties of star-forming galaxies at 2
Moutard, Thibaud. "Redshifts photométriques et paramètres physiques des galaxies dans les sondages à grande échelle : contraintes sur l'évolution des galaxies massives". Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4782.
Pełny tekst źródłaThis thesis presents the measurement of the photometric redshifts and physical parameters in the framework of large scale surveys, and their constraint on galaxy evolution. The photometric redshift measurement allows us to study the entire photometric sample. For this reason, the weak lensing signal measurement used in the Euclid mission as a primary cosmological probe will rely on photometric redshift measurements. However, the method is strongly affected by the quality of the photometry. In particular, I show in this thesis how the photometric calibration impacts the photometric redshift precison, in order to constrain the photometric strategy to use in the Euclid mission.Aiming to take into account for observationnal problems, the analysis is done with observationnal data whose photometric configuration is close to the expected Euclid one. These data combine new near-infrared observations conduected to cover the VIPERS spectroscopic survey and the CFHTLS photometry.Using the conclusions of this analysis, I have producted the new photometric catalogue for VIPERS and the associated photometric redshift calalogue.Finally, I used the same photometry to compute the stellar masses of 760,000 galaxies covering 22 square degrees at the limiting magnitude Ks(AB) < 22. This enabled me to study the evolution of the stellar mass function between redshifts z= 0.2 and z = 1.5. We have then shown that the star formation of galaxies with stellar masses around log(M/Msol) = 10.66 is stopped in 2-4 Gyr, while in quiescent low-mass (log(M/Msol) < 9.5) galaxies, the star formation has been stopped 5-10 times faster (approximatelly in 0.4 Gyr)
Starikova, Svetlana. "Clustering Analysis of Cosmic Sources at High Redshifts". Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3427463.
Pełny tekst źródłaLa tesi e' dedicata allo studio delle proprieta' di clustering di galassie normali e attive, in un ampio intervallo di redshift, dall'Universo locale fino a z>2. Queste sorgenti, selezionate nell’infrarosso con Spitzer e nei raggi X con Chandra, rappresentano diverse classi di oggetti ad alto redshift - AGN a z>1 che emettono nell'X, massicce galassie evolute a z~2 e galassie con formazione stellare a z~=1.7 e 0.7. Calcoliamo alcune misure di funzioni di correlazione angolare per questi oggetti e le combiniamo con dei modelli di clustering per gli aloni di materia oscura allo scopo di inferire le proprieta' di occupazione degli aloni per le diverse popolazioni di galassie. Inizialmente si sono discusse le proprieta' di clustering delle galassie con indicazioni di attivita' di formazione stellare, rilevate a 24 um da Spitzer. Usando i colori nell'ottico/vicino-IR, abbiamo suddiviso il campione in una popolazione a basso-redshift e in (
Liu, Jiayi. "Constraining the cosmic microwave background temperature evolution and the population and structure of galaxy clusters and groups from the South Pole Telescope and the Planck Surveyor". Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-172552.
Pełny tekst źródłaKollmeier, Juna Ariele. "The intergalactic medium absorption, emission, disruption /". Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1153856075.
Pełny tekst źródłaLiu, Jiayi [Verfasser], i Joseph [Akademischer Betreuer] Mohr. "Constraining the cosmic microwave background temperature evolution and the population and structure of galaxy llusters and groups from the South Pole Telescope and the Planck Surveyor / Jiayi Liu. Betreuer: Joseph Mohr". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1056876506/34.
Pełny tekst źródłaSarron, Florian. "Galaxy clusters in the cosmic web Searching for filaments and large-scale structure around DAFT/FADA clusters Weak lensing study of 16 DAFT/FADA clusters: Substructures and filaments". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS366.
Pełny tekst źródłaAs the most massive bound structures in the universe, galaxy clusters are a powerful probe of the impact of environment on galaxy evolution. In this work, I present AMASCFI, a new cluster finder algorithm using photometric redshifts I developed during the PhD and use the cluster catalogue obtained on the Canada France Hawaii Telescope Legacy Survey (CFHTLS) to investigate the role played by clusters and their environment on galaxy evolution. We show the good performances of AMASCFI on Euclid and the CFHTLS using mock data. In particular AMASCFI is 90% pure and 70% complete to z<0.7 for the latter. We then apply AMASCFI to the CFHTLS T0007, and infer a mass for each detected cluster using richness as a proxy. Using our cluster catalogue, we study the redshift evolution of the galaxy luminosity functions (GLFs) of early-type (ETGs) and late-type (LTGs) galaxies at different cluster masses. We observe that the ETG GLF faint-end drops at high redshift, the red sequence (RS) being already formed at z~0.7, but enriched by faint ETGs at z<0.7. This could be due to quenching of LTGs in the cluster or accretion of faint ETGs pre-processed in infalling groups. To investigate the role of pre-processing, we use the method of Laigle et al (2018) to detect filaments from photometric redshifts and show that it allows to recover the 3D cosmic web at CFHTLS accuracy. We apply it to the CFHTLS and detect filaments around AMASCFI clusters. Studying the distances of ETGs and LTGs in these filaments to clusters, we conclude that some quenching occurs in filaments. We suggest that this might be due to strangulation in galaxy groups though we still lack conclusive evidence for such a mechanism
Santiago, Bautista Iris del Carmen. "Étude des propriétés des galaxies dans les structures filamentaires". Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30034.
Pełny tekst źródłaThe baryonic component of the Large Scale Structure (LSS) of the Universe is composed by concentrations of gas and galaxies forming groups, clusters, elongated filaments and widely spread sheets which probably underline the distribution of dark matter. Nevertheless, according to the current cosmological models, most of the baryonic material in the Universe has not yet been directly observed. Numerical simulations suggest that from one-half to two-thirds of all baryons may be located out of clusters of galaxies, pervading the structures between them. The most concentrated structures, which we call systems of galaxies (i.e., groups and clusters) usually contain high density hot gas (1 - 10 keV) that cools radiatively, emits at X-rays wavelengths and interacts with the cosmic microwave background at millimeter wavelengths (Sunyaev Zel'dovich effect, SZ). For the less dense structures, filaments and sheets, the baryons are probably in moderately hot gas phase (0.01 - 1 keV), commonly named as warm hot intergalactic medium (WHIM). In this PhD Thesis, we study the environmental effects associated to the different components of the LSS. For the galaxy systems, we aim to characterize the intra cluster medium (ICM) through the analysis of the S-Z effect. We employ the ACT and Planck data to analyze the gas pressure profiles of a sample of low mass galaxy clusters. For the least dense structures, we assembled a sample of filament candidates composed by chains of clusters that are located inside superclusters of galaxies. We aim to probe the filament structure skeletons and characterize their components (galaxies, groups/clusters and gas)
Maciejewski, Michal. "Structures de l'espace des phases des halos de matière noire". Paris 6, 2008. http://www.theses.fr/2008PA066476.
Pełny tekst źródłaLombardo, Linda. "Explorer l'histoire de la Galaxie grâce à la spectroscopie stellaire". Electronic Thesis or Diss., Université Paris sciences et lettres, 2022. http://www.theses.fr/2022UPSLO011.
Pełny tekst źródłaThis thesis project presents several studies that are focused on the investigation of the chemical properties of different stellar populations in the Milky Way by means of high-resolution spectroscopy.The thesis is structured as follows:The first chapter is an introduction to the thesis project, and is divided into three sections. The first section describes the structure and formation scenarios of the Milky Way, in particular by referring to the most recent discoveries. The second section introduces the basic concepts and objectives of the studies presented in this thesis work. The third section describes the methods used to analyse the spectroscopic data.The second chapter presents the studies carried out in the context of the MINCE project. The first study is devoted to the chemical analysis of a sample of young giant stars that was serendipitously discovered during the first MINCE observations. My contribution in this work was to derive the stellar parameters, analyse the spectroscopic data, measure the rotational velocities, compare the results with theoretical models and write the paper. The second study presents the results obtained from the analysis of the first sample of MINCE stars. In this work, I contributed to the analysis of some of the stars in the sample.The third chapter presents the results obtained in the context of the CERES project. The first study presents a detailed chemical analysis of the star RAVE J110842.1-715300, with the aim of understanding whether or not it originated in the Omega Centauri globular cluster. My contribution in this study was to derive the stellar parameters of the star. The second study presents the results obtained for the CERES star sample. My contribution was to derive the parameters, compute model atmospheres, measure the chemical abundances, and write the paper.The fourth chapter presents the results obtained in the context of the High-speed stars project. The first study reports the results obtained from the high-resolution follow-up of two young and metal-poor stars in the sample of Caffau et al. (2020), to check whether they are blue stragglers or not. My contribution in this study was to obtain the high-resolution observations with UVES and to analyse the data. These results have not been published yet. The second study presents a detailed analysis of two high-speed stars observed with Subaru. In this study I was involved in the C abundance determination.The fifth chapter presents the results obtained from the chemical analysis of samples of stars selected using the Pristine photometry. The first study presents the chemical analysis of a sample of metal-poor stars that may have been enriched by the explosion of pair instability supernovae. My contribution was to select promising candidates and observe them with the SOPHIE spectrographat Observatoire de le Haute Provence (OHP)in visitor mode. The second study presents the preliminary results obtained from the chemical analysis of a sample of Pristine extremely metal-poor candidates. My contribution in this study was to derive the stellar parameters and the chemical abundances. The paper is in preparation.The sixth chapter concludes the thesis and gathers final reflections and future projects
Guglielmo, Valentina. "Groups and clusters of galaxies in the XXL survey". Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421945.
Pełny tekst źródłaQuesta tesi presenta uno dei primi censimenti delle proprietà delle galassie in gruppi ed ammassi selezionati nei raggi X a redshift intermedio, con lo scopo di valutare il ruolo dell'ambiente sull'assemblamento della massa stellare delle galassie, l'attività di formazione stellare e le proprietà delle popolazioni stellari osservate. Il mio progetto è inquadrato nella Survey XXL (Pierre et al., 2016), il più grande programma XMM-Newton approvato fino ad oggi, che copre due regioni extra-galattiche di 25 gradi quadrati ciascuna. Le sorgenti di raggi X estese ed identificate come gruppi ed ammassi sono state confermate spettroscopicamente e le loro proprietà principali sono caratterizzate o tramite misurazioni dirette o mediante relazioni di scala. Tra queste, le luminosità e le temperature X, le masse virali ed i raggi viriali sono di fondamentale importanza per lo sviluppo di questa tesi. Il grande vantaggio di XXL è che il campo XXL-Nord (XXL-N) è completamente coperto da osservazioni fotometriche e spettroscopiche provenienti dalle più recenti survey extra-galattiche di galassie. La disponibilità di una tale miniera di informazioni motiva lo sviluppo della mia ricerca sulle popolazioni di galassie nell'intervallo di redshift 0.1≤z≤0.6 nel campo XXL-N, esplorando gli ambienti più diversi dalle regioni di campo, ai gruppi, agli ammassi e ai superammassi. Il primo compito del mio lavoro consiste nella creazione di un campione spettrofotometrico omogeneo di galassie, pubblicato in Guglielmo et al. (2017), e adatto ad essere utilizzato in un'analisi scientifica. Il catalogo contiene redshift spettroscopici, informazioni sull'appartenenza a gruppi e ammassi, pesi di completezza spettroscopica in funzione della posizione nel cielo e magnitudine osservata, le masse stellari e le magnitudini assolute calcolate mediante una tecnica di spectral energy distribution (SED). Il catalogo è fondamentale per tutti gli studi all'interno della collaborazione XXL che mirano a correlare le proprietà ottiche derivate dalle galassie con informazioni sulle strutture X ed è ampiamente utilizzato nell'intera collaborazione XXL. Il catalogo spettrofotometrico pubblicato consente il primo risultato scientifico di questa tesi riguardante lo studio della funzione di massa stellare delle galassie (GSMF). L'obiettivo di questa analisi è di svelare se il processo di assemblamento della massa delle galassie dipende dall'ambiente cosiddetto globale, cioè dall'appartenenza al campo o a gruppi ed ammassi e, tra quest'ultimi, dalla luminosità X, utilizzata come proxy per la massa di alone. Ho eseguito l'analisi in quattro intervalli di redshift nel range 0.1≤z≤0.6, trovando nel complesso che l'ambiente non influenza la GSMF, almeno nell'intervallo di massa campionato. Il risultato è ulteriormente confermato dall'invarianza della massa media delle galassie membre rispetto alla luminosità X. Ho anche esaminato l'evoluzione della GSMF da z = 0.6 fino a z = 0.1, trovando che l'estremità della funzione a masse elevate è già formata nell'epoca più antica e non evolve, e rilevando invece un aumento del numero di galassie a bassa massa nello stesso intervallo di redshift. Questo studio è uno dei primi studi sistematici della GSMF condotto per sorgenti estese a raggi X che vanno da masse di alone tipiche di gruppi fino agli ammassi, ed è pubblicato nella seconda parte di Guglielmo et al. (2017). Avendo valutato l'indipendenza delle distribuzioni di massa rispetto all'ambiente globale, procedo a indagare se e in che misura l'ambiente influisce sull'attività di formazione stellare e sulle proprietà osservate delle popolazioni stellari delle galassie. Ho iniziato questa analisi dal superammasso più ricco identificato in XXL-N, XLSSsC N01, situato a redshift z~0.3 e composto da 14 gruppi ed ammassi. Questo lavoro è stato sottomesso in Guglielmo et al. (2018a). Concentrandosi sulla regione che circonda XLSSsC N01, ho diviso le galassie in diversi ambienti, che vanno dalle regioni virali di gruppi ed ammassi fino al campo, utilizzando una combinazione di parametrizzazioni ambientali globali e locali. I risultati principali di questo studio sono che, nell'ambiente del superammasso, mentre la frazione di galassie che formano stelle e l'efficienza di arresto dell'attività di formazione stellare dipendono fortemente dall'ambiente, lo stesso non vale per la relazione fra massa e tasso di formazione stellare (SFR). La frazione di galassie che formano stelle declina progressivamente dal campo ai filamenti fino alle regioni virializzate di gruppi ed ammassi, con un interessante aumento della stessa nelle regioni esterne delle strutture X. Inoltre, mentre la relazione media fra l'età delle galassie pesata per la luminosità (LW-age) e la massa stellare delle stesse è indipendente dall'ambiente, una chiara evidenza di una recente estinzione della formazione stellare si rileva nelle galassie passive situate nelle regioni virializzate delle strutture X. Infine, si estende l'analisi di questo particolare superammasso all'intero campo XXL-N. Questo lavoro sarà racchiuso in due articoli in preparazione (Guglielmo et al., 2018 b, c in preparazione). Grazie alla statistica più elevata dell'intero campione, ho studiato le proprietà delle galassie e la loro evoluzione nell'intervallo 0.1≤z≤0.5 in diversi ambienti, con l'obiettivo di caratterizzare il cambiamento nelle proprietà delle popolazioni stellari e la formazione della popolazione passiva al variare dell'ambiente. Oltre a distinguere tra le galassie di campo, e in gruppi ed ammassi (regioni virali e periferiche), mi sono concentrata anche su galassie situate in strutture di diversa luminosità X e sulle galassie situate all'interno di superammassi. Contemporaneamente, ho anche studiato le proprietà delle galassie situate a diverse densità locali proiettate (LD). In particolare, ho caratterizzato la frazione galassie con formazione stellare attiva / galassie blu e ho studiato la relazione fra massa e SFR, in funzione sia dell'ambiente globale che di quello locale. La frazione di galassie con formazione stellare attiva e di galassie blu è strettamente correlata all'ambiente, con il valore più basso nelle regioni virali di gruppi ed ammassi e il più alto nel campo. Nei membri esterni, la stessa frazione è simile a quella nel campo a z≥0.2 e assume valori intermedi rispetto ai membri virali e il campo a 0.1≤z<0.2. La relazione fra SFR e massa è anch'essa dipendente dall'ambiente, e in particolare il numero di galassie dei membri virali che hanno una ridotta SFR (galassie in transizione) risulta essere quasi il doppio di quella di galassie di campo. Ancora una volta, i membri esterni mostrano proprietà intermedie: la frazione di galassie in transizione è simile alla popolazione virale a z>0,3, ed in particolare risulta associata all'ambiente dei superammassi, e si riduce successivamente a valori tipici delle galassie di campo a 0.1≤z<0.3. Inoltre, la frazione di galassie attive nella formazione stellare e quella di galassie blu diminuiscono con l'aumentare della LD a tutti i redshift. Al contrario, la frazione di galassie in transizione non varia nello stesso intervallo LD. Queste differenze significative emergenti tra gli ambienti globali e locali sono intrinsecamente correlate al diverso significato fisico delle due parametrizzazioni, quindi ai diversi meccanismi fisici che agiscono sulle galassie quando sono legate al potenziale gravitazionale di un alone di materia oscura (secondo la definizione globale) o quando esposto ad interazioni con altre galassie in regioni densamente popolate (secondo la definizione locale). Durante le prime fasi del mio dottorato di ricerca, ho anche completato l'analisi della mia tesi magistrale, e riporto il testo completo del documento pubblicato in Appendice alla tesi (Guglielmo et al., 2015). I risultati sono strettamente correlati alle domande scientifiche trattate nel mio progetto di dottorato, ma vengono affrontate attraverso un approccio complementare, che mira alla ricostruzione della storia della formazione stellare delle galassie a basso redshift in ammassi e nel campo per studiare la dipendenza dall'ambiente globale, dalla massa stellare e dalla morfologia osservata.
Croton, Darren. "Galaxy Formation and Evolution". Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-44059.
Pełny tekst źródłaRuggiero, Rafael. "Galaxy Evolution in Clusters". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/14/14131/tde-14022019-140755/.
Pełny tekst źródłaNesta tese, nós visamos a contribuir para o entendimento do fenômeno da evolução de galáxias no ambiente de aglomerados de galáxias usando a metodologia de simulações numéricas. Para isso, desenvolvemos modelos hidrodinâmicos nos quais galáxias idealizadas ricas em gás movem-se em meio ao gás difuso de aglomerados de galáxias idealizados, permitindo um estudo detalhado e controlado da evolução destas galáxias neste ambiente extremo. O principal código usado em nossas simulações é o RAMSES, e nossos resultados tratam das mudanças em composição do gás, taxa de formação estelar, luminosidade e cor de galáxias caindo em aglomerados. Adicionalmente a processos acontecendo dentro das próprias galáxias, nós também descrevemos a dinâmica do gás que é varrido dessas galáxias com resolução sem precedentes para simulações dessa natureza (122 pc em uma caixa incluindo um aglomerado de 1e14 Msun inteiro), encontrando que aglomerados de gás molecular são formados nas caudas de galáxias que passaram por varrimento de gás por pressão de arraste, aglomerados estes que procedem a viver em isolamento em meio ao gás difuso de um aglomerado de galáxias por até 300 Myr. Esses aglomerados moleculares possivelmente representam uma nova classe de objetos; objetos similares foram previamente observados tanto em aglomerados quanto em grupos de galáxias, mas um tratamento compreensivo deles não foi apresentado até agora. Nós adicionalmente criamos um modelo hidrodinâmico para o sistema multi-aglomerado A901/2, e correlacionamos as condições do gás nesse modelo com a localização de uma amostra de galáxias jellyfish nesse sistema; isso nos permitiu inferir um possível mecanismo para a geração de morfologias jellyfish em colisões de aglomerados de galáxias em geral.
Curtis, Lake Emma. "Galaxy evolution with FMOS". Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:866b8ba5-5353-43a7-9898-a4b767ab0f6d.
Pełny tekst źródłaLinke, Laila Maria [Verfasser]. "Testing models of galaxy formation and evolution with galaxy-galaxy-galaxy lensing / Laila Maria Linke". Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1235524469/34.
Pełny tekst źródłaMartinet, Nicolas. "Galaxy clusters : a probe to galaxy evolution and cosmology". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066348/document.
Pełny tekst źródłaThis thesis presents some recent results concerning galaxy evolution and cosmology,based on the observation of galaxy clusters at optical wavelengths. We first introduce the main properties of galaxy clusters (Sect. 1.1) and how they can be used for cosmology within the standard cosmological model (Sect. 1.2). A large fraction of the presented results comes from the study of the DAFT/FADA galaxy cluster survey at redshifts 0.4 < z < 0.9 (Sect. 1.3). We divide our study in two parts according to the observable that is considered: galaxy luminosity or galaxy shape. The distribution of galaxy luminosities is called the galaxy luminosity function (GLF), which can be used to probe the evolution of cluster galaxies (Sect. 2.1). Computing the GLFs for a sub sample of 25 DAFT/FADA clusters, we find that faint blue star forming galaxies are quenched into red quiescent galaxies from high redshift until today. Comparing to the field shows that this transformation is more efficient in high density environments.We also study the fraction of baryons in galaxy groups and clusters (Sect. 2.2). Wefind that in groups, the stars contained in galaxies can reach masses of the same order as those of the intra-cluster gas, while in clusters they are usually negligible relatively to the gas. Taking both stars and gas into account we constrain the matter density parameter Galaxy shapes are distorted by foreground objects that bend light in their vicinity. This lensing signal can be exploited to measure the mass distribution of a foreground cluster. We review the basic theory of weak lensing and shear measurement (Sect. 3.1), and then apply it to a subsample of 16 DAFT/FADA clusters, with Subaru/SuprimeCam or CFHT/MegaCam imaging (Sect. 3.2). We estimate the masses of these clusters, and take advantage of the large fields of view of our images to detect filaments and structures in the cluster vicinity, observationally supporting the hierarchical scenario of cluster growth. Finally, we detect shear peaks in Euclid-like simulations, and use their statistics as a cosmological probe, similarly to cluster counts (Sect. 3.3). We forecast the cosmological constraints that this technique will achieve when applied to the Euclid space mission, and develop a tomographic analysis that adds information from redshifts. We conclude with a discussion of our perspectives on future studies in all the fieldsinvestigated in the present thesis
Cool, Richard Jacob. "Empirical Measurements of Massive Galaxy and Active Galaxy Evolution". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195540.
Pełny tekst źródłaNoeske, Kai Gerhard. "Optical and near infrared studies of the photometric structure and starburst activity of blue compact dwarf galaxies". Doctoral thesis, [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969518021.
Pełny tekst źródłaThomas, Daniel. "Chemical evolution and galaxy formation". Diss., lmu, 2000. http://nbn-resolving.de/urn:nbn:de:bvb:19-4637.
Pełny tekst źródłaBothwell, Matthew Stuart. "Galaxy evolution : near and far". Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/265602.
Pełny tekst źródłaMoustakas, John. "Spectral Diagnostics of Galaxy Evolution". Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/305142.
Pełny tekst źródłaOsmond, John Peter Francis. "The evolution of galaxy groups". Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422727.
Pełny tekst źródłaShabala, Stanislav. "AGN feedback in galaxy evolution". Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612309.
Pełny tekst źródłaDavidge, Helen. "Probing galaxy evolution with AKARI". Thesis, Open University, 2017. http://oro.open.ac.uk/49554/.
Pełny tekst źródłaRomano, Donatella. "Chemical evolution and galaxy formation". Doctoral thesis, SISSA, 2002. http://hdl.handle.net/20.500.11767/4041.
Pełny tekst źródłaThomas, Nicole. "Galaxy Clustering as a Probe for Galaxy Evolution in Simulations". University of the Western Cape, 2017. http://hdl.handle.net/11394/6206.
Pełny tekst źródłaStudying clustering on small scales (<10Mpc) over a large span of red- shifts allows us to connect galaxies to underlying cosmic large-scale structure, and thereby provide constraints on the physical processes that drive galaxy evolution. Relatedly, studying the relative bias of galaxies and their halo occupancy quanti es how the underlying dark matter distribution is traced by baryons in galaxies. Comparing model predictions to current and future multi-wavelength galaxy surveys, en- ables a greater understanding of how galaxy formation processes impact the relationship between galaxies and dark matter
Saghiha, Hananeh [Verfasser]. "Comparing galaxy-galaxy(-galaxy) lensing in semi-analytic models and observations to study galaxy evolution / Hananeh Saghiha". Bonn : Universitäts- und Landesbibliothek Bonn, 2017. http://d-nb.info/113070467X/34.
Pełny tekst źródłaGlazebrook, Karl. "An infrared study of galaxy evolution". Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/28109.
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