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Pius, A., and E. V. Shkarupa. "Environmental sanitation policy and solid waste management in Sunyani municipality." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/31698.
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Solid Waste management is one of the least recognized public policy issues in Ghana. Quite apart from the obvious physical unattractiveness of the business, waste management often competes with more pressing economic and social issues such as fiscal and trade matters, unemployment and poverty, education and health. Even within the domain of environmental sustainability, the management of waste has had to play second fiddle to more apparently manifest challenges such as land and coastal degradation, biodiversity loss, and climate change. Waste management, however, remains a major challenge for any society, since all natural processes generate waste. The particular economic, social and environmental circumstances of the Sunyani municipality make this issue especially critical for medium to long-term sustainable development.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/31698
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Kusi, Hinneh. "Managing junior secondary schools in Sunyani Municipality (Ghana) : the challenges for headteachers and their professional development needs." Thesis, University of Leicester, 2008. http://hdl.handle.net/2381/4099.
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The study investigated the challenges for Junior Secondary School headteachers (both male and female) in the Sunyani municipality of Ghana and their professional development needs. Ghana is a developing country in West Africa facing the challenge of improving educational provision at different levels. This was a qualitative study underpinned by interpretive philosophical thought. It employed a case study approach and collected data in two phases using semi-structured questionnaire and semi-structured interview. In the first phase, a questionnaire was distributed to all headteachers and Circuit Supervisors (school inspectors) in the municipality, while the second phase involved semi-structured interviews with a purposive maximum variation sample of headteachers and Circuit Supervisors who had already responded to the questionnaire. The study highlighted that the headteachers faced multiple challenges. These included teachers’ lack of commitment and uncooperative attitude; non-involvement of the headteachers in making decisions that affected their professional practice; the complexity and multiplicity of their roles and responsibilities; and insignificant responsibility allowances. The study identified the factors responsible for these problems. The study also identified ways of preparing aspiring headteachers for meeting the demands in the educational context. Specifically, it identified the skills and competences they required and the training opportunities for the provision of those competences as well as strategies for meaningful selection/ appointment of headteachers and their induction. The findings suggested that the in-service training /continuing professional development programmes organised in Sunyani municipality for practising headteachers were inappropriate for enhancing their professional growth and development. The study proposed ways/strategies for improving some aspects of the programmes for meaningful professional development of the headteachers. This research also unveiled additional in-service training/continuing professional development opportunities for the headteachers in that context, including regional-based courses and a cluster-based collaborative headship scheme.
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Grainger, William Frank. "Using the Sunyaev-Zel'dovich effect." Thesis, University of Cambridge, 2001. https://www.repository.cam.ac.uk/handle/1810/251795.
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This work is concerned with the Sunyaev-Zel'dovich (S-Z) effect in clusters of galaxies and its use in cosmology. In Chapter 2, I consider possible causes of error in the determination of <I>H</I><SUB>0</SUB> from the uncertain geometry of clusters and complications such as lack of virialisation. From numerical simulations, I find that with 20 clusters, the resultant error is 8%. Chapter 3 details and tests a new maximum likelihood algorithm for the removal of contaminating radio sources. Two new estimates of <I>H</I><SUB>0</SUB> are presented, 78<SUP>+26</SUP><SUB>-20</SUB> dm s<SUP>-1</SUP> Mpc<SUP>-1</SUP> for 0016+16 and 40<SUP>+14</SUP><SUB>-11</SUB> km s<SUP>-1</SUP> Mpc<SUP>-1</SUP> for A611. In chapters 4 and 5 I describe a search for new clusters via extended steep-spectrum radio emission due to merger events or head-tail sources. A candidate sample of possible high-redshift clusters is produced based on S<SUB>326MHz</SUB> > 65 mJy and α<SUP>1.4GHz</SUP><SUB>0.3GHz</SUB> > 1.5. Six of these were then used as targets for S-Z observations; no unequivocal detection was found implying each cluster has a total mass ≲ 10<SUP>15</SUP> <I>M</I><SUB>⊙</SUB>. Optical <I>V, R</I><SUB>S</SUB> and <I>I</I> follow-up in two of the fields shows two galaxies in each field with <I>V -</I> <I>R</I><SUB>S<I> </I></SUB>≈ 3 and <I>R</I><SUB>S</SUB> ≈ 20; similar observations of blank fields show no such galaxies and hence these are good candidate cluster members at <I>z</I> = 0.5-0.6.
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Hennig, Christina. "The galaxy population evolution of Sunyaev." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-184237.
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This thesis presents a study of the galaxy populations in massive galaxy clusters that have been selected via the Sunyaev - Zeldovich Effect from the South Pole Telescope. The clusters have multiband optical imaging data from the Dark Energy Survey (DES). Each cluster has a robust mass estimate and with the deep DES data they cover a redshift range between 0 and 1.1. This makes it an ideal cluster sample to study evolutionary trends of the galaxy populations with mass and redshift.
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Portsmouth, Jamie 1974. "Polarization in the Sunyaev-Zeldovich effect." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/17016.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2003.<br>Includes bibliographical references (p. 121-125).<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>A novel covariant formalism for the treatment of the transfer and Compton scattering of partially polarized light is presented. In this approach, the polarization state of a light beam is described by a tensor constructed from the time average of quadratic products of the electric field components in a local observer frame. This leads naturally to a covariant description which is ideal for calculations involving the boosting of polarized light beams between Lorentz frames, and is more flexible than the traditional Stokes parameter approach in which a separate set of polarization basis vectors is required for each photon. The covariant kinetic equation for Compton scattering of partially polarized light by relativistic electrons is obtained in the tensor formalism by a heuristic semi-classical line of reasoning. The kinetic equation is derived first in the electron rest frame in the Thomson limit, and then is generalized to account for electron recoil and allow for scattering from an arbitrary distribution of electrons. This formalism is applied to a calculation of the relativistic corrections to the spectral distortions imprinted in the intensity and polarization of the cosmic microwave background radiation (CMB) by inverse Compton scattering in clusters of galaxies (the Sunyaev-Zeldovich effects). We develop a Monte Carlo method for simulating these effects, based on the tensor formalism and kinetic equation. We also consider the use of the polarization signal generated by scattering of the CMB from distant clusters as a probe of cosmological perturbations.<br>(cont.) Such observations allow an indirect measure of the CMB quadrupole as seen on the last scattering surfaces of observers at nonzero redshift. The statistical properties of this signal in a simple cosmological model are derived. We demonstrate that measurements of this signal would yield more information than is available from observations of the CMB anisotropies on our sky, and would potentially allow more precise measurement of cosmological parameters and the primordial power spectrum of density fluctuations.<br>by Jamie Portsmouth.<br>Ph.D.
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Geisbüsch, Jörn. "Cosmology with Sunyaev-Zelʼdovich cluster surveys". Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613080.
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Jones, Michael Edward. "Aperture synthesis observations of the Sunyaev-Zel'dovich effect." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357766.
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Chen, Nan-chieh. "Menschsein als Dialog und Shūnyatā : eine transkulturelle Studie zur Schwerstbehindertenpädagogik /." Berlin ; Münster : Lit, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2956113&prov=M&dokv̲ar=1&doke̲xt=htm.
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Grainge, Keith. "Measuring the Hubble constant via the Sunyaev-Zel'dovich effect." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264501.
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Schammel, Michel Philippe. "Blind Sunyaev-Zel'dovich survey with the Arcminute Microkelvin Imager." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648243.
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Holanda, Rodrigo Fernandes Lira de. "O efeito Sunyaev-Zel\'dovich: teoria e aplicações cosmológicas." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/14/14131/tde-13092011-135337/.
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O efeito Sunyaev-Zel\'dovich (ESZ) é uma das mais promissoras técnicas de investigação cosmológica envolvendo os aglomerados de galáxias e a radiação cósmica de fundo (RCF). Tal efeito é uma modificação no espectro planckiano da RCF devido à interação dos fótons com os elétrons energéticos que permeiam o meio intra-aglomerado. Nesta tese de doutorado, vinculamos alguns parâmetros cosmológicos e investigamos a estrutura dos aglomerados de galáxias. Para tal, consideramos amostras de aglomerados para os quais existem medidas conjuntas do ESZ e do brilho em Raios-X. Duas amostras são consideradas, a saber: os 25 dados compilados por de De Filippis et al. (2005), na qual os aglomerados são descritos por modelos isotérmicos (esférico e elíptico), e os 38 dados da amostra de Bonamente et al. (2006) que utilizam um modelo esférico, não isotérmico. Inicialmente, nós investigamos as implicações das diferentes descrições na obtenção do parâmetro de Hubble, $H_0$, no contexto do modelo $\\Lambda$CDM plano e em cosmologias mais gerais, como o $XCDM$ plano e $\\Lambda$CDM com curvatura. Os resultados dependem da amostra e das hipóteses subjacentes. Mostramos que a análise conjunta envolvendo o ESZ/Raios-X de aglomerados, as oscilações acústicas dos bárions e o parâmetro de desvio ({\\it shift parameter}) constituem uma técnica interessante para se determinar $H_0$ e que seu valor depende apenas fracamente da curvatura e do parâmetro da equação de estado da energia escura. Analisando as diversas amostras, nós obtemos também que a descrição elíptica de De Filippis et al. (2005) é a que melhor se ajusta com medidas independentes da física de aglomerados. Posteriormente, utilizando dados de aglomerados (ESZ/Raios-X) e adotando uma des\\-crição puramente cinemática do Universo, obtemos que a probabilidade do parâmetro de desaceleração ser negativo é de 92\\% para a amostra de Bonamente et al. (2006) e de 72\\% para o caso elíptico De Filippis et al. (2005). Ainda nesta linha, simulando os resultados dos vários mapeamentos de Sunyaev-Zeldovich que estão em andamento, discutimos a capacidade dessa técnica (em combinação com dados de Raios-X de aglomerados) para vincular parâmetros cosmológicos. Por outro lado, considerando que a obtenção das distâncias de diâmetro angular de aglomerados pela técnica do ESZ/raios-X depende da relação de dua\\-lidade, investigamos as conseqüências desta dependência de duas formas distintas: (i) testando a consistência entre a validade estrita da relação no modelo de concordância cósmica e as suposições utilizadas para descrever os aglomerados, e (ii) Considerando distâncias independentes (luminosidade e diâmetro angular) obtidas das supernovas Ia e dos aglomerados de galáxias, nós propomos um novo teste para a relação de dualidade que além de auto-consistente é independente de modelo cosmológico. Finalmente, para este teste, discutimos também influência dos diferentes tipos de ajuste das curvas de luz de supernovas. Nossos vínculos para $H_0$ e as conseqüências estatísticas baseadas na relação de dualidade, fornecem uma nova evidência de que a verdadeira geometria dos aglomerados tem uma forma elíptica. Tais resultados também reforçam o interesse pela pesquisa observacional de SZE e de raios-X de aglomerados em moderados e altos {\\it redshifts}.<br>The so-called Sunyaev-Zeldovich effect (SZE) is one of the most promising techniques for cosmological investigations involving galaxy clusters and the cosmic background radiation (CMB). Such an effect is a modification of the Planckian spectrum due to the interaction between the CMB photons and the hot electrons filling the intracluster medium. In this PhD thesis, we constrain some cosmological parameters and investigate the structure of galaxy clusters based on some samples for which the cluster are endowed with simultaneous measurements of SZE and X-ray surface brightness. Two different samples of galaxy clusters are considered, namely: the 25 data compiled by De Fillippis et al. (2005), and the 38 data sample of Bonamente et al. (2006), based on the non-isothermal spherically symmetric model. Initially, we constrain the value of the Hubble parameter, $ H_0 $, by taking into account the different assumptions underlying the galaxy cluster samples in the context of a flat $\\Lambda$CDM model, as well as, for more general cosmologies like the flat XCDM model and $\\Lambda $CDM with curvature. The results depend on the model assumptions and samples. It is also found that a joint analysis involving ESZ/Raios-X of clusters, the baryon acoustic oscillations (BAO) and shift parameter, constitutes an interesting technique for constraining the Hubble parameter and that its value is weekly dependent on the curvature, as well as on the equation of state parameter of the dark energy. By analysing the different samples, we conclude that the elliptical description of the De Filippis et al. (2005) provides the best quality description in comparison with measurements that are independent from galaxy clusters physics. Furthermore, by using galaxy cluster data (SZE/X-ray) and adopting a purely kinematical description for the universal expansion, we obtain that the decelerating parameter is negative with 92 \\% and 72 \\% of the probability by using the Bonamente et al. (2006) and De Filippis et al. (2005) samples, respectively. By simulating future data set, the ability of the ongoing SZE observations to obtain tighter constraints on the expansion history through SZE/X-ray technique is also discussed. On the other hand, since the SZE/X-ray technique for measuring angular diameter distance of clusters depends on the cosmic distance duality relation (DD relation) validity, we investigate the consequences of such a dependence in two distinct ways: (i) we test the consistence between the strict validity of DD relation in the framework of the $\\Lambda$CDM model (WMAP7) and the different assumptions underlying the galaxy cluster geometries, and (ii) we propose a self-consistent and model-independent test for the DD relation by using type Ia supernovae and galaxy clusters data. Finally, for such a test, we also analyse the influence of the different supernovae light curve fitter methods. Our constraints for $H_0$ and the statistical consequences of the distance duality relation provide a new evidence that the true geometry of galaxy clusters is provided by the elliptical form. Such results also reinforce the interest for the observational research involving the Sunyaev-Zeldovich and X-rays from galaxy clusters at moderate and high {\\it redshifts}.
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Taburet, Nicolas. "L'effet Sunyaev-Zel'dovich dans l'analyse du fond diffus cosmologique." Paris 11, 2010. http://www.theses.fr/2010PA112322.
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Une nouvelle génération de relevés mesure actuellement les anisotropies du fond diffus cosmologique (FDC) aux petites échelles angulaires et va permettre de tester plus avant le modèle standard de la cosmologie. A ces petites échelles les anisotropies primaires sont dominées par celles, secondaires, dues à l'effet Sunyaev-Zel'dovich (SZ) des amas de galaxies. La signature spectrale caractéristique de l'effet SZ permet de construire des catalogues d'amas et d'en soustraire la contribution au FDC primaire. Cependant les résidus SZ des amas non résolus sont susceptibles de biaiser l'estimation des paramètres cosmologiques lors de l'analyse du FDC. Je développe une méthode analytique permettant de calculer ces biais et l'applique au cas d'un relevé de type Planck. Mon travail montre que l'estimation de la valeur de l'indice spectral du spectre des fluctuations initiales peut être biaisée à hauteur de plusieurs sigmas. Suite à ce constat, je développe une méthode permettant d'extraire l'information cosmologique simultanément des spectres de puissance du FDC et du SZ en prenant en compte l'entière dépendance cosmologique du signal SZ. Je compare mon approche avec celles actuellement employées et propose une réanalyse des données FDC déjà publiques (ACBAR, ACT, SPT, WMAP). Je présente également une méthode originale pour mettre en évidence l'effet Sachs-Wolfe intégré, signe de la présence d'énergie sombre dans un univers euclidien. L'effet SZ est utilisé pour tracer la distribution de matière et l'exploitation de sa signature fréquentielle caractéristique permet d'uniquement employer des données FDC. Enfin, je discute des contaminants pouvant affecter cette détection<br>Second generation cosmic microwave background (CMB) experiments are now measuring the CMB anisotropies at arcminute scales so as to further test the standard LambdaCDM cosmological model. At those small scales, the secondary anisotropies due to the galaxy clusters Sunyaev-Zel'dovich (SZ) effect dominate over the primary ones. Using the SZ effect characteristic spectral signature, one can build galaxy clusters catalogues and remove their secondary contribution from the primary CMB. Some level of SZ residuals will nevertheless remain in the CMB data and their contribution to the CMB angular power spectrum is likely to bias cosmological parameter estimation. I develop an analytical method to calculate those biases and apply it to the study case of a Planck like mission. The results show that SZ residuals can bias the estimation of the spectral index at a level of several times the expected accuracy on that parameter. Consequently I develop a coherent method that allows us to simultaneously extract cosmological information from the CMB and SZ power spectra and that fully accounts for the SZ spectrum dependency with cosmology. I compare this new approach to those frequently used, and present a reanalysis of the latest public CMB data (ACBAR, ACT, SPT, WMAP). The last section of my manuscript presents an original method to extract the integrated Sachs-Wolfe effect, that is a powerful dark energy probe in a euclidean universe, out of pure CMB data. This is made possible using the SZ effect, which traces the matter distribution, and exploiting its spectral signature. Finally, I discuss the possible contaminations to this ISW-SZ detection
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Edgington, Samantha Faye Lange Andrew E. "A galaxy cluster survey using the Sunyaev Zel'dovich effect /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-09272003-154928.
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Di, Mascolo Luca [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "Probing the intracluster medium at high angular resolution via radio-interferometric measurements of the Sunyaev-Zeldovich effect / Luca Di Mascolo ; Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1214593356/34.
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Staniszewski, Zachary K. "First Galaxy Clusters Discovered Via the Sunyaev Zel-D'ovich Effect /." Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1271698482.
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Thesis (Doctor of Philosophy)--Case Western Reserve University, 2010<br>Department of Physics Title from PDF (viewed on 2010-05-25) Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
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Lyskova, Natalya [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "Mass determination of elliptical galaxies / Natalya Lyskova. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1050648129/34.
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Kennedy, James 1983. "The APEX-SZ experiment : observations of the Sunyaev Zel'dovich effect." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116109.
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The Sunyaev Zel'dovich effect (SZE) is a secondary distortion of the cosmic microwave background (CMB) spectrum produced by galaxy clusters that allows for measurements of intra-cluster gas properties. Current experiments are using large arrays of multiplexed transition-edge sensor bolometers to achieve the sensitivities required for SZE cluster surveys and targeted cluster SZE observations. This thesis describes the APEX-SZ experiment, the first instrument to produce scientific results from observations with such an array. The scientific motivation for the APEX-SZ experiment is discussed, followed by a description of the APEX-SZ experiment and frequency domain multiplexing technologies. We have developed a custom data reduction pipeline for the experiment which uses a variety of filters, both in the temporal and spatial domain to produce 1' resolution maps of the SZE at 150GHz. The results of data analysis for the Bullet cluster (lE0657-56) and Abell 2204 (A2204) are presented. Both clusters are assumed to be isothermal and in hydrostatic equilibrium, allowing a fit to an isothermal beta-model and subsequent mass fraction estimates. The maximum likelihood parameters and constant likelihood 68% confidence intervals are estimated using a Markov-Chain Monte Carlo method to sample the beta-model parameter space. We measure cluster gas mass fractions with r 2500 to be 0.140 +/- 0.035 and 0.058 +/- 0.035 for the Bullet cluster and A2204 respectively. The Bullet gas mass fraction is consistent with previous results from X-ray analysis. The gas mass fraction for A2204 does not agree well with other A2204 observations, however the large scatter in the gas mass fractions determined from previous X-ray and SZE analyses indicates that a more complex density model may be appropriate for this cluster.
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Cunha, da Silva AntoÌnio JoseÌ. "The Sunyaev-Zel'dovich effect : predictions from hydrodynamical N-body simulations." Thesis, University of Sussex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247972.
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Runyan, Marcus Christian Lange Andrew E. "A search for galaxy clusters using the Sunyaev-Zel'dovich effect /." Diss., Pasadena, Calif. : California Institute of Technology, 2003. http://resolver.caltech.edu/CaltechETD:etd-05292003-125239.
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Shimwell, Timothy William. "Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager." Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/241039.
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In this thesis I discuss my work on the Arcminute Microkelvin Imager (AMI). I focus on the detection of Sunyaev-Zel'dovich (SZ) signatures at 14-18GHz. Once the background science and operation of the instrument are described I proceed to present my contribution to the calibration of AMI, including: primary beam measurements; refinements to the known antenna geometry and flagging geostationary satellite interference. This is followed by an outline of the software that I have developed to subtract sources from visibilities, concatenate data from multiple observations, simulate data, and perform jack-knife tests to evaluate the magnitude of systematic errors. The Bayesian analysis that I use to obtain parameter estimates and to quantify the significance of putative SZ detections is described. I perform realistic simulations of clusters and use these to characterisethe analysis. I then, for the first time, apply the analysis to data from the AMI blind cluster survey. I identify several previously unknownSZ decrements. Finally, I conduct pointed observations towards a high luminosity subsample of eight clusters from the Local Cluster Substructure Survey(LoCuSS). For each of these I provide probability distributions of parameters such as mass, radius, and temperature. I compare myresults to those in the literature and find an overall agreement.
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Zenteno, Alfredo. "Galaxy populations in galaxy clusters selected by the Sunyaev-Zeldovich Effect." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-170507.
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We present a study of the galaxy populations in massive galaxy clusters selected by their Sunyaev–Zel’dovich Effect (SZE) signatures. Selection via the SZE is approximately mass- limited where the mass limit varies only slightly with redshift, making it an ideal selection method for studying the evolution of the galaxy content of clusters. We begin by introducing the SZE, the South Pole Telescope (SPT), and the larger research project in which this Thesis is embedded. We then present the core galaxy population studies of this Thesis.
In Chapter 3, we present the first large-scale follow-up of an SZE-selected galaxy cluster sample. Of 224 galaxy cluster candidates in the sample, we optically confirm 158 clusters and measure their photometric redshifts. We find a redshift range of 0.1
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Horner, Piers Francis. "1.1mm Bolocam observations of the Sunyaev Zel'dovich increment in Abell 1835." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55186/.
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Over recent years, there has been an increasing level of interest in the cosmological significance of observations of the Sunyaev Zel'dovich (SZ) effect in galaxy clusters. Al though the SZ effect has been known about for around fifty years, observations of it have only become mainstream recently. The SZ effect refers to the redistribution of energy of Cosmic Microwave Background (CMB) photons due to inverse Compton scattering off populations of free electrons, most commonly in galaxy clusters. The SZ acts as an artificial 'emitter' or 'absorber' along the line of sight to a cluster once other back grounds have been removed. SZ measurements suffer from a range of systematic effects that have made observations in the region of the spectrum where the SZ simulates an 'emitter' (above 220 GHz) particularly challenging. Nevertheless, the scientific potential of large-scale SZ surveys is large. In particular, the SZ distortion to the CMB is independent of redshift and limited only by the mass of the clusters being observed. This makes SZ surveys useful for making detailed observations of the evolution of large-scale structure of the Universe, which depends sensitively on cosmological parameters. Knowledge of the spectrum of the SZ effect can also be used to constrain the peculiar velocity of galaxy clusters, which has the potential to provide information about the nature of dark energy. This thesis describes the observation, mapping and detailed analysis of the cluster Abell 1835 at 1.1 mm, where the SZ acts as an 'emitter'. An estimate of the SZ emission from Abell 1835 is obtained and combined with other measurements of the cluster to generate a spectrum, from which one of the most precise limits on a cluster's peculiar velocity to date is obtained.
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Mecoli, Davide. "Processi di scattering e applicazioni astrofisiche." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14771/.
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L'elaborato contiene la descrizione fisica dei processi di scattering Thomson, Compton e Compton inverso. Sono trattati i fenomeni di Comptonizzazione, Synchrotron Self Compton, Catastrofe Compton ed Effetto Sunyaev-Zeldovich nel panorama astrofisico. Nell'elaborato sono inclusi due articoli scientifici pubblicati in "The Astronomical Journal", in particolare l'effetto Sunyaev-Zeldovich impiegato per la determinazione della Costante di Hubble.
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Hancock, Stephen. "Detections of structure in the cosmic microwave background." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338307.
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Soraisam, Monika Devi [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "Novae : a theoretical and observational study / Monika Devi Soraisam. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1102897213/34.
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Mineo, Stefano [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "X-ray emission from star-forming galaxies / Stefano Mineo. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1015500900/34.
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Chen, Hailiang [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "Modelling accreting white dwarf populations in galaxies / Hailiang Chen. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1113534583/34.
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Allison, J. R. "Observations of the Sunyaev-Zel'dovich effect using the Cosmic Background Imager 2." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:c6b10ecf-3b50-4c2a-9ee1-0fe8dd93e580.
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This thesis describes the analysis of pointed thermal Sunyaev-Zel'dovich (SZ) effect data from observations using the Cosmic Background Imager 2 (CBI2). CBI2 is an upgrade to the original Cosmic Background Imager, with antennas that have twice the effective collecting area, and hence provide greater sensitivity on longer baselines. Observations of the thermal SZ effect constrain the line-of-sight integrated gas pressure within clusters of galaxies and, when combined with X-ray data, provide an excellent tool for deriving the physical properties of these large structures. The CBI2 SZ data combine relatively low-resolution with a large field-of-view, and can therefore be used to constrain the gas properties of medium-redshift clusters out to the virial radius. By jointly fitting a suitable analytical model to SZ data and X-ray surface brightness data, it is possible to obtain constraints on the temperature and total mass of the cluster. For the analysis work presented in this thesis I choose to parametrise the gas based upon the known behaviour of the entropy, and the total mass by the Navarro, Frenk and White (NFW) prescription. This model is tested against Hydrodynamic/N-body simulations and is found to reproduce the radial behaviour of key cluster properties. The CBI2 observations presented in this work focus on the REFLEX-DXL clusters, an X-ray luminous sub-sample of the REFLEX survey at z ~ 0.3, which have previously published X-ray surface brightness data. The Bullet Cluster, a significant merger system, is a member of this sample and is presented here as a case study for use of the entropy-based model. The derived total mass and gas mass fraction of this cluster are found to be consistent with results from previous X-ray observations. The derived properties from the REFLEX-DXL sample are used to construct a preliminary set of SZ scaling relations out to the virial radius, and are found to be consistent with the self-similar model for massive clusters.
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Puisieux, Sarah. "Etude des effets Sunyaev-Zel'dovitch cinétique et relativiste dans les données Planck." Phd thesis, Université Paris-Diderot - Paris VII, 2013. http://tel.archives-ouvertes.fr/tel-01019928.
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Les effets Sunyaev-Zel'dovitch (SZ) correspondent à la diffusion inverse-Compton des photons du fond diffus cosmologique sur le gaz des amas de galaxies. Ce travail a visé à étudier l'ensemble des aspects des effets SZ cinétique et relativiste dans les données Planck. Pour ce faire, nous avons développé des filtres adaptés, conçus spécialement pour la détection des effets SZ. Ces filtres nous ont permis d'utiliser l'ensemble des longueurs d'onde de l'expérience de façon optimale. L'effet SZ cinétique est proportionnel à la vitesse radiale particulière des amas de galaxies. Nous avons donc pu étudier, grâce à cet effet SZ, les vitesses radiales particulières via des analyses individuelles, mais aussi statistiques. En particulier, il nous a permis d'effectuer les premières mesures de la vitesse moyenne des amas. Cette vitesse moyenne s'est avérée compatible avec zéro et constitue une vérification du principe cosmologique. Par ailleurs, nous avons étudié le dipôle des amas de galaxies, exclu les modèles inhomogènes d'Univers à un grand niveau de confiance et établi des limites supérieures sur la variance des vitesses des amas. L'effet SZ cinétique est aussi exploré au travers du moment moyen des paires de halos de galaxies. Les résultats obtenus ont montré une détection significative. Enfin, nous avons étudié l'effet SZ relativiste via sa dépendance à la température des amas. Nous avons montré en particulier son impact sur l'estimation de l'effet SZ cinétique.
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Hurier, Guillaume. "Etude des amas de galaxies avec l'expérience PLANCK, via l'effet Sunyaev-Zel'dovich." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00849126.
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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.
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Trevisan, Marina. "Estudo da possibilidade de observação do efeito sunyaev-zel'Dovich nos mapas WMAP." Instituto Nacional de Pesquisas Espaciais, 2007. http://urlib.net/sid.inpe.br/mtc-m17@80/2007/07.02.16.42.
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Observações do efeito Sunyaev-Zeldovich (SZ) são de grande interesse em estudos de cosmologia e para o mapeamento das grandes estruturas do universo. Este efeito corresponde a uma pequena distorção no espectro da Radiação Cósmica de Fundo (RCF) causado por espalhamento Compton inverso dos fótons da RCF por elétrons presentes no gás em aglomerados de galáxias e é independente do redshift do aglomerado. Neste trabalho são apresentados a metodologia desenvolvida e os resultados da observação do efeito SZ nos mapas das bandas Q (41 GHz), V (61 GHz) eW(94 GHz) do satélite Wilkinson Microwave Anisotropy Probe (WMAP). Os perfis radiais da variação de temperatura da RCF causada pelo efeito SZ são determinados para uma amostra de 42 aglomerados de galáxias. Estes sao comparados com os perfis esperados, determinados a partir de dados em raios-X destes aglomerados, considerando o modelo beta isotérmico e o efeito de diluição pelo feixe do WMAP. A comparação é feita baseada na diferença entre os decrementos centrais dos perfis esperados e observados, ponderada pelas incertezas envolvidas. O decremento de temperatura médio encontrado corresponde a cerca de 1/3 do esperado. A diferença entre os decrementos de temperatura previsto e observado é, em média, 0, 119±0, 014 mK com nível de confiabilidade de 95%. Parte da inconsistencia entre os resultados obtidos e esperados pode ser explicada pela presença de fatores que afetam as observações do efeito SZ, tais como emissao Galáctica, fontes de rádio, subestruturas, ruído do instrumento e as flutuações primárias da RCF, que possuem amplitude da ordem do próprio efeito SZ. Excluindo os aglomerados que possivelmente são afetados por estes processos, diminui-se a inconsistencia entre os dados em raios-X e WMAP, obtendo uma diferença entre previsto e observado de 0, 059 ± 0, 026 mK com nível de confiabilidade de 95%.<br>The Sunyaev-Zeldovich (SZ) effect offers a unique and powerful observational tool in cosmology and in large scale structure studies. It is a spectral distortion of the cosmic microwave background (CMB) caused by inverse Compton scattering of CMB photons by hot electrons present in the central regions of galaxy clusters, and is insensitive to the redshift of the cluster. In this work, the methods and results of SZ effect observations using Wilkinson Microwave Anisotropy Probe (WMAP) data in Q (41 GHz), V (61 GHz) and W (94 GHz) bands are presented. The radial profiles of the temperature deviation of the CMB are obtained for a sample of 42 clusters of galaxies. These profiles are compared to the expected profiles, inferred by considering the isothermal beta model derived from X-ray data and taking into account the WMAP point spread function. The comparison is performed considering the difference between the central values of the predicted and observed profiles, weighted by the uncertainties involved. The average observed SZ decrement only accounts for about 1/3 of the expected decrement. The difference between predicted and observed decrements is 0.119 ± 0.014 mK at 95% confidence level. Part of this discrepancy between expected and observed decrements can be explaned by the presence of factors that affect SZ measurements, such as Galaxy emission, radio sources, substructures, instrument noise and CMB fluctuations, with amplitudes of the order of the SZ effect itself. Excluding clusters that are prone to contamination, the discrepancy between X-ray and WMAP data is reduced, resulting in a difference between predicted and observed decrements of 0.059 ± 0.026 mK, at 95% confidence level.
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Adam, R., I. Bartalucci, G. W. Pratt, et al. "Mapping the kinetic Sunyaev-Zel’dovich effect toward MACS J0717.5+3745 with NIKA." EDP SCIENCES S A, 2017. http://hdl.handle.net/10150/623249.
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Measurement of the gas velocity distribution in galaxy clusters provides insight into the physics of mergers, through which large scale structures form in the Universe. Velocity estimates within the intracluster medium (ICM) can be obtained via the Sunyaev-Zel'dovich (SZ) effect, but its observation is challenging both in term of sensitivity requirement and control of systematic effects, including the removal of contaminants. In this paper we report resolved observations, at 150 and 260 GHz, of the SZ effect toward the triple merger MACS J0717.5 + 3745 (z = 0.55), using data obtained with the NIKA camera at the IRAM 30 m telescope. Assuming that the SZ signal is the sum of a thermal (tSZ) and a kinetic (kSZ) component and by combining the two NIKA bands, we extract for the first time a resolved map of the kSZ signal in a cluster. The kSZ signal is dominated by a dipolar structure that peaks at -5.1 and + 3.4 sigma, corresponding to two subclusters moving respectively away and toward us and coincident with the cold dense X-ray core and a hot region undergoing a major merging event. We model the gas electron density and line-of-sight velocity of MACS J0717.5 + 3745 as four subclusters. Combining NIKA data with X-ray observations from XMM-Newton and Chandra, we fit this model to constrain the gas line-of-sight velocity of each component, and we also derive, for the first time, a velocity map from kSZ data (i. e. that is model-dependent). Our results are consistent with previous constraints on the merger velocities, and thanks to the high angular resolution of our data, we are able to resolve the structure of the gas velocity. Finally, we investigate possible contamination and systematic effects with a special care given to radio and submillimeter galaxies. Among the sources that we detect with NIKA, we find one which is likely to be a high redshift lensed submillimeter galaxy.
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Ip, Lai-Kwan Regin. "Vision of sunyata-wu (void) : towards a processual perspective of social work /." [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16155.pdf.
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Puisieux, Sarah. "Etude de l'effet Sunyaev-Zel'dovich cinétique et relativiste dans les données Planck." Paris 7, 2013. http://www.theses.fr/2013PA077232.
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Les effets Sunyaev-Zel'dovitch (SZ) correspondent à la diffusion inverse-Compton des photons du fond diffus cosmologique sur le gaz des amas de galaxies. Ce travail a visé à étudier l'ensemble des aspects des effets SZ cinétique et relativiste dans les données Planck. Pour ce faire, nous avons développé des filtres adaptés, conçus spécialement pour la détection des effets SZ. Ces filtres nous ont permis d'utiliser l'ensemble des longueurs d'onde de l'expérience de façon optimale. L'effet SZ cinétique est proportionnel à la vitesse radiale particulière des amas de galaxies. Nous avons donc pu étudier, grâce à cet effet SZ, les vitesses radiales particulières via des analyses individuelles, mais aussi statistiques. En particulier, il nous a permis d'effectuer les premières mesures de la vitesse moyenne des amas. Cette vitesse moyenne s'est avérée compatible avec zéro et constitue une vérification du principe cosmologique. Par ailleurs, nous avons étudié le dipôle des amas de galaxies, exclu les modèles inhomogènes d'Univers à un grand niveau de confiance et établi des limites supérieures sur la variance des vitesses des amas. L'effet SZ cinétique est aussi exploré au travers du moment moyen des paires de halos de galaxies. Les résultats obtenus ont montré une détection significative. Enfin, nous avons étudié l'effet SZ relativiste via sa dépendance à la température des amas. Nous avons montré en particulier son impact sur l'estimation de l'effet SZ cinétique<br>The Sunyaev-Zeldovich effects correspond to the inverse-Compton diffusion of photons from the cosmic microwave background on the gaz of clusters of galaxies. The aim of this work is to study ail the aspects of kinetic and relativistic thermic SZ in the Planck data. We have developec several filters, specially designed to extract the SZ effects. These filters allow us to use ail the Planck frequencies in an optimal way. The kinetic effect is proportional to the radial peculiar velocity of clusters of galaxies. We have studied these velocities individually but also statistically. We have in particular measured for the first time the average velocity of clusters, that is found in agreement with zero, which constitutes a proof of the cosmological principle. We have also studied the bulk flow of clusters and excluded several models of inhomogeneous universe with a very high confidence and put an upper limit on the velocity variance. The kinetic SZ effect can also be explored through the pairwise momentum of halos of galaxies. The results present a significant detection. Finally, we have analyzed the thermal relativistic SZ effect via its dependency to cluster temperatures. We have in particular provided evidence of its impact on the measurement of the kinetic SZ effect
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Contreras, Radovic Cristian. "La teoria del big bang y la doctrina de Nagarjuna: el vacío o sunyata como síntesis ontológica de todo cuanto existe." Doctoral thesis, Universitat Autònoma de Barcelona, 2004. http://hdl.handle.net/10803/5162.
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Mi tesis doctoral investiga la Teoría del Big Bang sobre el origen del universo y su relación con la doctrina del sabio filósofo budista, Nagarjuna (India s.II-III), fundador de la Vía Media o Camino Medio del budismo, según su obra genuina titulada Mûla-mâdhyamaka-kârik_, un texto decididamente auténtico, opus magna de este autor conforme la tradición india, china y tibetana, prueba indiscutible de la historicidad de su figura. Nagarjuna, uno de los cuatro soles que iluminan al mundo desde sus cuatro direcciones, maestro espiritual de Oriente y Occidente, fue el creador de la escuela budista Mâdhyamaka viva en la India desde el siglo II al VI. <br/>La teoría científica de la Gran Explosión Universal o Big Bang concluye que el "vacío" es la fuente energética de donde surge el Cosmos: nuestro origen. La Doctrina de Nagarjuna prueba que el "vacío" es la esencia más profunda de la Realidad; un sistema filosófico consistente con las descripciones físicas contemporáneas acerca del campo de fuerza que da principio al Cosmos.<br/>De ahí que esta Tesis Doctoral se intitule: La Teoría del Big Bang y la Doctrina de Nagarjuna: el vacío o s_nyat_ como síntesis de todo cuanto existe. Una construcción teórica fundamentada en el principio según el cual filosofía y ciencia tienen un carácter universal y no están basadas únicamente en la cultura, es decir, responde a la autoridad de la experiencia, de los hechos empíricos. El texto se inscribe en el marco paradigmático de la Filosofía de la Ciencia y contempla un enfoque sincrético, ecléctico, multidisciplinar y holístico. <br/>El principal objetivo ha sido centrar la investigación en la temática cosmológica de la filosofía de Nagarjuna, es decir, en la verdad última sobre la naturaleza de todas las cosas, el origen del universo; si bien también posee implicancias soteriológicas, epistemológicas, gnoseológicas y éticas, de primera magnitud, en especial, para quienes estamos interesamos en el futuro de nuestra Cultura Occidental.<br/>El tema de la Introducción son los conceptos científicos centrales de la Teoría del Big Bang. <br/>En el Capítulo I abordo el Estado de la Cuestión. La aparición historiográfica del budismo en Occidente y de la figura de Nagarjuna. Además realizo un registro completo de autores, editores y traductores que han escrito sobre Nagarjuna en Occidente.<br/>En el Capítulo II elaboro un examen crítico de la obra literaria nagarjuniana centrándome en la temática cosmológica del corpus, sin descuidar la ética y ascética. Me refiero a una descripción racional y crítica a las ediciones. Preciso el privilegio de unos textos sobre otros, para centrarme en la Mûla-mâdhyamaka-kârik_, de la cual realizo una primera traducción al castellano de la traducción al francés del original tibetano de Georges Driessens, Traité du Milieu, Seuil, 1995; la única traducción completa al castellano existente del citado texto fundamental.<br/>En el Capítulo III pruebo que la visión del origen del universo de la actual ciencia occidental encuentra paralelos objetivos en el budismo oriental de nuestro autor, Nagarjuna, particularmente al considerar el concepto de vacío; una especie de leit motiv que une y sintetiza dichas corrientes de pensamiento, filosofía y ciencia. Profundizamos el estudio del significado de s_nyat_ o vacío y de la vacuidad, y realizamos un resumen de la Doctrina de Nagarjuna en su Camino Medio a la iluminación del hombre y la sociedad. Así observamos que las teorías y modelos principales de la física moderna conducen a una visión del mundo que es internamente consistente con el sistema filosófico de Nagarjuna.<br>My doctoral thesis studies the Big Bang Theory about the origin of the universe and his relationship with the doctrine of the buddhist philosopher Nagarjuna (India s.II-III), founder of Buddhism of the Middle Way, in accord with his genuine work, titled: Mûla-mâdhyamaka-kârik_; an authentic text, opus magna of this author in accord with the india, chinese and tibetan tradition, clear probe of the history of his figure. Nagarjuna, one of the four suns witch illuminated the world in the four directions, spiritual master of Orient and Occident, was the creator of the Buddhist Mâdhyamaka school lived in India from centuries II to VI. <br/>The Big Bang theory concludes that the vacuum is the main energy from which one emerge the Cosmos. Nagarjuna´s doctrine probe that the sunyata (or vacuum) is the most deep essence of the Reality; a philosophical vision that is consistent with the physics description about the force who permitted the beginning of the universe, that means, about the latest natural essence of all things. A theoretical construction founded in the principle that philosophy and science has a universal character, not only based on a unique culture, that means, respond to the experience authority and the empirical facts. I inscribed the thesis in a syncretism, eclectic, multisciplinary and holistic point of view. <br/>In the Introduction I describe the mains concepts of the Big Bang's theory.<br/>In Chapter I begin the description of the appearance of buddhism in Occident and Nagarjuna's figure. I made a complete register of the bibliography of authors, editors and translater about Nagarjuna. <br/>In Chapter II I made a critic exam of nagarjuna's works focused in the cosmological thematic. I privilege the Mûla-mâdhyamaka-kârik_, and I made a first translation to spanish from the french translation of the tibetan original of Georges Driessens, Traité du Milieu, Seuil, 1995; the first, unique and complete spanish translation of this fundamental text.<br/>In Chapter III I probe that the contemporary universe vision of the west scientific have objectives parallels with Nagarjuna's buddhism, in particular, with the vacuum concept or sunyata. My main intention is show that the scientific vision of the vacuum is similar to the Nagarjuna's sunyata, a kind of leit motiv between the modern science and budhhist philosophy. We are in front of a definition of the same thing and in the same sense, but from different disciplines; wherever, not only in front of a mere parallelism, but in front of a synthetic of the first magnitude and resonance, with a main significant for the World Culture.<br/>The Big Bang is a cosmological physic theory with naturals questions to philosophy and religion. We're in the ultimate limit of the universe, the exact place where we suppose is home's God. This scene is singular for faith and reason's history. What kind of philosophical adventure propose the contemporary physics to the World Culture? What kind of enigma take place now to the human spirit? <br/>The actual moment of cosmology is similar to the state of the Ptolemaic theory before Copernicus. The matrix of such a research impose to postulate new cosmic ingredient of a unknown essence -hot dark matter, cool dark matter, dark energy and additional new dimension of space-time-; and the biggest work is the unification between General Relativity and Quantum Mechanic, the way to describe -maybe- the initial instant of the Cosmos, full of fundamental questions. But this it is not the complete picture. <br/>On the other side, we need a new fundamental gnoseological paradigm between faith and reason, if our will is continuing. The philosophical vision complements the physic. My personal conviction is that only the synthesis between faith-reason, Orient-Occident, will be at last the most useful and powerful line of thinking for the Third Millennia. I see the present thesis in this paradigm of Philosophy of Science, in order to reject any conflict perspective between science, philosophy and religion.
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Enriquez, Karen Bautista. "Interrupting the conversation on kenosis and sunyata: Buddhist and Christian women in search of the relational self." Thesis, Boston College, 2011. http://hdl.handle.net/2345/bc-ir:104404.
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Thesis advisor: John Makransky<br>The purpose of this dissertation is to contribute to Christian theological anthropology by bringing in the "interruption" of another religious tradition, Buddhism, in order to see how key Buddhist doctrines such as emptiness and practices of meditation may inform aspects of the Christian feminist discussions of kenosis in the spiritual life, and the search for a relational self. It also seeks to enhance Buddhist-Christian dialogue by bringing the "interruption" of feminist voices from both the Buddhist and Christian traditions into conversation with each other in order to see what they might offer, not only towards the search for "right relationship," but also towards bringing about the re-integration of doctrine and spiritual practices for more effective action in the world today. In the first part of the dissertation, I lay out the background of these two concepts of kenosis and emptiness within their respective religious traditions including the Buddhist-Christian dialogues around these two concepts. I then look at how Christian feminists (Sarah Coakley and Mary Grey) as well as Buddhist feminists (Anne Klein and Rita Gross) critique the traditional interpretations of these concepts and how they reconstruct such concepts in their articulation of a relational self and in their argument for the importance of practice and its relationship with doctrine. In the second part of this dissertation, I focus on the comparison between these Buddhist and Christian feminists and how they can mutually learn from each other. I argue that Buddhist feminist discussions on emptiness and meditation enhances and deepens the Christian feminist articulations of kenosis and how an empowered self can be found through a kenotic spirituality. I also demonstrate how such a dialogue can bring us back to the rich resources within the Christian tradition, such as the image of Mary and Marian devotions. Furthermore, I show how this feminist comparison contributes back to Buddhist-Christian dialogue by including the voices of women and their concern for suffering and the importance of praxis in our interreligious encounters today<br>Thesis (PhD) — Boston College, 2011<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Theology
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Tanimura, Hideki. "Probing the large-scale structure of the Universe with the Sunyaev-Zel'dovich Effect." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63189.
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The Sunyaev-Zeldovich (SZ) effect is a spectral distortion in the Cosmic Microwave Background (CMB), due to up-scattering of CMB photons by high energy electrons in clusters of galaxies or any cosmic structure. The Planck satellite mission has measured the spectral distortion with great sensitivity and has produced a full-sky SZ (y) map, which can be used to trace the large-scale structure of the Universe.
In this dissertation, I construct the average SZ (y) profile of ∼ 65,000 Luminous Red Galaxies (LRGs) from the Sloan Digital Sky Survey Data Release 7 (SDSS/DR7) using the Planck y map and compare the measured profile with predictions from the cosmo-OWLS suite of cosmological hydrodynamical simulations. This comparison agrees well for models that include feedback from active galactic nuclei (AGN feedback).
In addition, I search for the SZ signal due to gas filaments between ∼260,000 pairs of LRGs taken from the Sloan Digital Sky Survey Data Release 12 (SDSS/DR12), lying between 6-10 h −1 Mpc of each other in the tangential direction and within 6h −1 Mpc in the radial direction. I find a statistically significant SZ signal between the LRG pairs. This is the first detection of gas plausibly located in filaments, expected to exist in the large-scale structure of the universe. I compare this result with the BAHAMAS suite of cosmological hydrodynamical simulations and find that it predicts a slightly lower, but marginally consistent result.
As an extension of my MSc. thesis work, I study CMB polarization. The B-mode component of CMB polarization is an important observable to test the theory of inflation in the early universe. However, foreground emissions in our own galaxy dominates the B-mode signal and therefore multi-frequency observations will be required to separate any CMB signal from the foreground emission. I assess the value of adding a new low-frequency channel at 10 GHz for the foreground removal problem by simulating realistic experimental data. I find that such a channel can greatly improve our determination of the synchrotron component which, in turn, significantly improves the reliability of the CMB separation.<br>Science, Faculty of<br>Physics and Astronomy, Department of<br>Graduate
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Komarov, Sergey [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "Thermal conduction in hot gas of galaxy clusters / Sergey Komarov ; Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1114068209/34.
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Chase, Simon Timothy. "A millimetre-wavelength search for the Sunyaev-Zeldovich effect in clusters of galaxies." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37656.
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Soergel, B., S. Flender, K. T. Story, et al. "Detection of the kinematic Sunyaev–Zel'dovich effect with DES Year 1 and SPT." OXFORD UNIV PRESS, 2016. http://hdl.handle.net/10150/621727.
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We detect the kinematic Sunyaev-Zel'dovich (kSZ) effect with a statistical significance of 4.2 sigma by combining a cluster catalogue derived from the first year data of the Dark Energy Survey with cosmic microwave background temperature maps from the South Pole Telescope Sunyaev-Zel'dovich Survey. This measurement is performed with a differential statistic that isolates the pairwise kSZ signal, providing the first detection of the large-scale, pairwise motion of clusters using redshifts derived from photometric data. By fitting the pairwise kSZ signal to a theoretical template, we measure the average central optical depth of the cluster sample, (tau) over bar (e) = (3.75 +/- 0.89) x 10(-3). We compare the extracted signal to realistic simulations and find good agreement with respect to the signal to noise, the constraint on (tau) over bar (e), and the corresponding gas fraction. High-precision measurements of the pairwise kSZ signal with future data will be able to place constraints on the baryonic physics of galaxy clusters, and could be used to probe gravity on scales greater than or similar to 100 Mpc.
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Herbig, Thomas Readhead Anthony C. S. "A measurement of the Sunyaev-Zeldovich effect in the coma cluster of galaxies /." Diss., Pasadena, Calif. : California Institute of Technology, 1994. http://resolver.caltech.edu/CaltechETD:etd-09102008-151722.
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Soergel, Bjoern. "The kinematic and thermal Sunyaev-Zel'dovich effects as probes of cosmology and astrophysics." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277657.
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A small fraction of cosmic microwave background (CMB) photons scatter off electrons in the ionised gas in collapsed structures. This process, known as the Sunyaev-Zel'dovich effect, is usually broken down into a thermal (tSZ) and a kinematic (kSZ) contribution. While the former is sensitive to the random velocities of the electrons in the hot gas, the latter is sourced by the bulk motion of the entire object. In this thesis I measure the signature of both of these effects by cross-correlating CMB data with different tracers of the large-scale structure. I further study how these effects can be used as probes of cosmology and astrophysics. I first report a statistically significant detection of the kSZ effect. This is achieved by combining a cluster catalogue derived from the first year data of the Dark Energy Survey with CMB temperature maps from the South Pole Telescope. I perform the measurement with a differential statistic that isolates the pairwise kSZ signal, providing the first detection of the large-scale motion of clusters using redshifts derived from photometric data. By fitting the pairwise kSZ signal to a theoretical template, I measure the average central optical depth of the cluster sample. I compare the extracted signal to simulations and find good agreement with respect to the signal-to-noise, the constraint on the optical depth, and the corresponding gas fraction. I next study the potential of the kSZ effect as a probe of cosmology, again focussing on the pairwise method. The main challenge is disentangling the cosmologically interesting mean pairwise velocity from the cluster optical depth and the associated uncertainties on the baryonic physics in clusters. Using the Magneticum cosmological hydrodynamical simulations I calibrate a scaling relation between the amplitude of the tSZ signal and the optical depth. I show that this relation can be used to recover an accurate estimate of the mean pairwise velocity from the kSZ signal, and that this effect can therefore be used as a probe of cosmology. I finally derive constraints on feedback from active galactic nuclei by setting limits on their tSZ signal. By combining all-sky microwave, sub-mm, and far-infrared data from the Planck and AKARI satellites, I break the degeneracy between the tSZ signature and extragalactic dust emission. I test the measurement pipeline with a catalogue of galaxy clusters, finding the expected high-significance tSZ detection together with correlated dust emission. I then measure the tSZ signal of spectroscopically confirmed quasi-stellar objects (QSOs), but obtain only a low-significance hint of a tSZ signature. This analysis leads to a lower mean thermal energy than reported in some previous studies which were contaminated by dust emission. A comparison of these results to hydrodynamical simulations can be used as a probe of QSO host masses.
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Ruppin, Florian. "Cosmologie via les observations d'amas de galaxies par effet Sunyaev-Zel'dovich avec NIKA2." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAY029/document.
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La distribution de masse dans l'Univers telle que tracée par les amas de galaxies constitue une sonde cosmologique puissante. La caractérisation des processus associés à l'origine et à la croissance des grandes structures permet de contraindre des paramètres cosmologiques via l'étude de la distribution des amas en fonction de leur masse et de leur redshift. Cependant, il existe un désaccord statistiquement significatif observé entre les contraintes cosmologiques établies par l'étude des anisotropies primaires du fond diffus cosmologique et celles issues de l'analyse de la distribution des amas de galaxies. Cela pourrait signifier que le modèle standard de la cosmologie est incomplet. L'une des méthodes d'observation des amas de galaxie exploite l'effet Sunyaev-Zel'dovich (SZ) qui permet de contraindre la pression du gaz contenu dans ces derniers. Cette observable peut être directement liée à la masse des amas via une relation d'échelle et un profil de pression. Il est donc essentiel de caractériser précisément ces derniers afin de limiter les potentiels biais et effets systématiques affectant les analyses cosmologiques. Cette thèse présente l'ensemble des travaux réalisés dans cet objectif. Elle porte sur des thématiques allant des observations SZ effectuées avec la caméra NIKA2 installée au télescope de 30 mètres de l’IRAM jusqu'à l'estimation des paramètres cosmologiques en passant par l'analyse des données brutes de NIKA2 et des cartes SZ réalisées.Une part du travail de thèse présenté dans ce document est consacrée à l'étude et l’amélioration des différentes étapes effectuées, depuis les observations d'amas de galaxies au télescope avec la caméra NIKA2 jusqu'à la production de cartes de l'effet SZ. Les procédures développées pour estimer les performances instrumentales de NIKA2 sont détaillées et la chaîne d'analyse utilisée pour réduire les données brutes est présentée.Les travaux réalisés dans cette thèse ont également consisté à caractériser les propriétés thermodynamiques d'amas de galaxies via des analyses jointes combinant les cartes SZ NIKA2 avec des données X mesurées par le satellite XMM-Newton. Nous détaillons les méthodes employées dans le logiciel de traitement des données SZ créé pour le grand programme SZ de NIKA2, la procédure de déprojection non-paramétrique développée pour caractériser le profil de pression des amas de galaxies et les résultats de la première observation SZ avec NIKA2.Les dernières activités présentées sont dédiées aux analyses réalisées afin de quantifier l'impact du grand programme SZ de NIKA2 sur la cosmologie. Nous analysons l'effet des perturbations dynamiques du milieu intra-amas sur la caractérisation du profil de pression avec NIKA2 via l'utilisation d'amas de la simulation numérique MUSIC. Finalement, nous détaillons l'étude permettant d'estimer l'impact d'une variation du profil de pression universel sur l'estimation des paramètres cosmologiques déduite du spectre de puissance de l'effet SZ mesuré par Planck<br>The mass distribution in the Universe, as traced by galaxy clusters is a powerful cosmological probe. The characterization of the processes associated with the origin and the growth of the large scale structures enables constraining cosmological parameters by studying the distribution of clusters according to their mass and redshift. However, a tension is observed between the cosmological constraints established by the study of the primary anisotropies of the cosmological background and those resulting from the analysis of the distribution of galaxy clusters. This may imply that our cosmological model is incomplete. The observation of clusters from the Sunyaev-Zel'dovich (SZ) effect allows us to constrain their gas pressure. This observable can be directly linked to the mass of galaxy clusters via a scaling relation and a pressure profile. It is thus essential to characterize the latter precisely in order to limit the potential bias and systematic effects affecting cosmological analyses. This thesis presents the work carried out to this end. It covers topics ranging from SZ observations made with the NIKA2 camera installed at the IRAM 30-metre telescope to the estimation of cosmological parameters, and including the analysis of NIKA2 raw data and the SZ maps produced.Part of the thesis work presented in this document is dedicated to the study and the improvement of the different tasks carried out, from the observations of galaxy clusters with the NIKA2 camera to the production of maps of the SZ effect. The procedures developed to estimate the NIKA2 instrumental performance are detailed and the analysis pipeline used to analyze the raw data is presented.The work carried out in this thesis also consisted in characterizing the thermodynamic properties of galaxy clusters using joint analyzes that combine the NIKA2 SZ maps with X-ray data measured by the XMM-Newton satellite. We detail the methods used in the SZ data processing software created for the NIKA2 SZ large program, the non-parametric deprojection procedure developed to characterize the pressure profile of galaxy clusters and the results of the first SZ observation with NIKA2.The last activities presented are dedicated to the analyses carried out to quantify the impact of the NIKA2 SZ large program on cosmology. We analyze the effect of dynamic disturbances of the intracluster medium on the characterization of the pressure profile with NIKA2 via the use of clusters from the MUSIC N-body simulation. Finally, we detail the study realized in order to estimate the impact of a modification of the universal pressure profile on the estimation of cosmological parameters derived from the power spectrum of the SZ effect measured by Planck
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SILVA, NETO Gival Pordeus da. "Testando a robustez na determinação da constante de hubble, H0, via observáveis em redshifts intermediários." Universidade Federal de Campina Grande, 2015. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1988.
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Previous issue date: 2015-05-08<br>Capes<br>A constante de Hubble (H0) é considerada fundamental na cosmologia. Ela é crucial
para qualquer modelo cosmológico moderno, pois está relacionada com diversas grandezas cosmológicas, portanto, é de extrema importância a determinação mais restritiva e acurada possível do seu valor. A mais recente estimativa de H0 a partir de métodos locais (z 1), H0 = 73:8 2; 4 kms1Mpc1, e a partir de redshifts muito altos (z ' 1070), H0 = 67; 3 1; 2 kms1Mpc1, são discrepantes em um nível de con fiança de 2; 4 . Dentro deste contexto, Lima e Cunha (LC), a m de lançar alguma luz sobre este problema, derivou uma nova determinação de H0 utilizando quatro testes cosmológicos em redshifts intermediários (z 1), com base no chamado modelo CDM Plano. Eles obtiveram H0 = 74; 1 2; 2 kms1Mpc1, em pleno acordo com as medições locais. Neste trabalho, exploramos a robustez do resultado de LC, procurando por erros sistemáticos e a sua dependência com o modelo cosmológico usado. Nós constatamos que o valor H0 a partir desta análise conjunta é muito fracamente dependente de modelos cosmológico, mas a morfologia adotada para inferir o raio central dos aglomerados de galáxias, altera o resultado, sendo a principal fonte de erros sistemáticos. Concluímos que uma melhor compreensão da morfologia dos aglomerados é fundamental para transformar esse método em um poderoso estimador de H0.<br>The Hubble constant (H0) is considered a fundamental constant of cosmology. It is
crucial for any modern cosmological model, it is related to various cosmological quantities,
so it is extremely important a restrictive and accurate determination of its value. The
most recent estimate of H0 from local observations (z 1), H0 = 73:8 2; 4 kms�1Mpc�1,
and from high redshifts (z ' 1070), H0 = 67; 3 1; 2 kms�1Mpc�1, are discrepant in a
con dence level of 2; 4 . Within this context, Cunha and Lima (LC), in order to shed
some light on this problem, derived a new determination of H0 using four cosmological
tests at intermediate redshifts (z 1), based on the model called Flat CDM. They
obtained H0 = 74; 1 2; 2 kms�1Mpc�1, in full agreement with local measurements. In
this work, we explore the robustness of the result LC looking for systematic errors and
its dependence on the cosmological model used. We found that the H0 value from this
combined analysis is very weakly dependent on the underlying cosmological model, but the morphology adopted to infer the core radius of galaxy clusters, changes the estimates being the main source of systematic errors. Hence, we conclude that a better understanding of the morphology of the clusters is essential to transform this method in a powerful cross-check to H0.
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Tenzin, Kencho. "Shankara a Hindu revivalist or a crypto-Buddhist? /." unrestricted, 2006. http://etd.gsu.edu/theses/available/etd-11302006-094652/.
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Thesis (M.A.)--Georgia State University, 2006.<br>Kathryn McClymond, committee chair; Jonathan Herman, Christopher White, committee members. Electronic text (70 p.) : digital, PDF file. Description based on contents viewed Apr. 20, 2007; title from title screen. Includes bibliographical references (p. 60-61).
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Hennig, Christina [Verfasser], and Joseph [Akademischer Betreuer] Mohr. "The galaxy population evolution of Sunyaev-Zeldovich selected clusters / Christina Hennig. Betreuer: Joseph Mohr." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1074358716/34.
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Koliopanos, Filippos [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "X-ray diagnostics of ultra-compact X-ray binaries / Filippos Koliopanos. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1073825965/34.
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Valkonen, Laura Elina. "The Sunyaev-Zel'dovich effect in galaxy clusters as a tool for estimating cosmological parameters." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487558.
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Clusters of galaxies provide us with a sensitive probe with which to study the Universe. Their mass function is strongly dependent on the cosmological parameters, which govern the dynamical evolution of the Universe and they also provide a representative sample of ~he Universal matter distribution. The Sunyaev-Zel'dovich effect (SZE) is a promising method for detecting clusters out to their form.ation redshift and has also been shown to be a good estimator for cluster masses, A combination. of X-ray and SZE data can also be used to measure the dista:nce to the cluster, independently of the cosmic distance ladder, allowing a measurement of the Hubble Constant. However, the success of SZE methods is highly dependent on a detailed understanding of the physics of galaxy clusters. We have undertaken a multi-wavelength survey of 8 ga:laxy clusters, the Viper Sunyaev-Zel'dovich Survey (VSZS), in order to assess and highlight the issues which may be encountered by upcoming large scale SZE surveys. Such surveys will not be able to study individual clus- . ters in great detail and will be reliant on the ·accuracy of scaling relations and assumed cluster models. \Ve have therefore imaged each cluster in our sample simultar;eously at three frequencies (150GHz, 220GHz and 280GHz) with the Arcminute Cosmology Bolometer Array Receiver (ACBAR), and have followed-up with X-ray observations (Chandra and XMM-Newton) and some optical observations (Gemini), in order to carry out a detailed analysis of the cluster ICM structure. We have made some of the highest significance detections of the SZE to date. Several clusters were detected at two frequencies, as a temperature increment at 280 GHz and a decrement at 150 GHz and some of these clusters were also resolved by the observations. Most of the VSZS sample were detected as SZE signals for the first time. Although Abell 3667 and lE0657-56 had been detected previously, these were now detected at two frequencies for the first time. We have added the results of the four fully analyzed VSZS clusters to the Y- T relation of Bonamente et al. (2007) and have found our points to lie well within the scatter of the relation, except fOr cluster A3112, which has possible radio source contamination. We have also found that cluster temperatures estimated from the Y - T relation are better overall at tracing the X-ray spectral temperature than the Lx - T derived temperatures.
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Nagarajan, Aarti [Verfasser]. "Mass calibration of the Sunyaev-Zel'dovich effect using APEX-SZ galaxy clusters / Aarti Nagarajan." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1177881705/34.
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Novaes, Camila Paiva. "Identificação de aglomerados de galáxias em mapas da RCFM utilizando o efeito Sunyaev Zel'dovich." Instituto Nacional de Pesquisas Espaciais, 2011. http://urlib.net/sid.inpe.br/mtc-m19/2011/02.09.13.23.
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A Radiação Cósmica de Fundo em Microondas (RCFM) é considerada um dos mais importantes observáveis astrofísicos. O entendimento das propriedades (espectro, distribuição angular e polarização) que caracterizam esse campo de radiação são de extrema importância para o estudo da formação das estruturas que hoje observamos no Universo. Existem também processos secundários de produção de flutuações de temperatura, gerados após a recombinação, que podem mascarar o sinal primário da RCFM, atrapalhando o estudo de suas propriedades intrínsecas. Um desses processos é o chamado efeito Sunyaev-Zel'dovich (SZ), causado por espalhamento Compton inverso dos fótons da RCFM. Além de sua importância específica para o estudo da RCFM, a combinação de medidas do efeito SZ com medidas em raios X pode ser usada, por exemplo, para estudar a distribuição de aglomerados por intervalo de \textit{redshift} (e, consequentemente, as flutuações de matéria que originaram as estruturas em grande escala) e estimar observáveis cosmológicos como a constante de Hubble e a relação diâmetro angular - distância. O satélite Planck, lançado em 2009 pela Agência Espacial Européia, é dedicado ao estudo da RCFM e um dos resultados esperados da análise de seus dados é a separação dos sinais contaminantes da RCFM, entre eles o efeito SZ. Este trabalho apresenta a análise da distribuição de aglomerados SZ em simulações de mapas de RCFM produzidos pelo satélite Planck. Os aglomerados foram produzidos a partir de perfis de temperaturà do tipo "$\beta$ isotérmico" e, em seguida, combinados com mapas sintéticos da RCFM, gerados em formato Healpix, para testar um algoritmo de identificação do tipo "blind survey", que será utilizado nos mapas reais. O JADE (\textit{Joint Approximate Diagonalization of Eigenmatrices}) é um algoritmo baseado na Análise de Componentes Independentes (ICA) e é efetivo na extração de componentes não-gaussianas. Os resultados mostram que o JADE e todo procedimento adotado é eficiente na identificação da posição e intensidade do efeito SZ em cada aglomerado, recuperando cerca de 92\% deles para o caso em que os mapas de entrada são compostos pela combinação linear de RCFM, efeito SZ, emissão síncrotron, de poeira, livre-livre e ruído instrumental, simulados utilizando N$_{side}$ = 1024. Esta porcentagem varia de acordo com o N$_{side}$ utilizado, características do ruído e número de emissões incluídas nos mapas analisados.<br>The Cosmic Microwave Background (CMB) is considered one of the most important astrophysical observables. The understanding of the properties (spectrum, angular distribution and polarization) that characterize this radiation field is of utmost importance for the study of structure formation in the universe we see today. There are also secondary processes for the production of temperature fluctuations, generated after the recombination, which can mask the primary signal of the CMB, hindering the study of their intrinsic properties. One such process is called the Sunyaev-Zel'dovich effect (SZ), caused by inverse Compton scattering of CMB photons. In addition to its specific importance for the study of CMB, the combination of SZ effect measurements with X-ray measurements can be used, for example, to study the distribution of clusters per \textit{redshift} interval (and hence the fluctuations of matter that gave rise to large-scale structure) and to estimate cosmological observables such as the Hubble constant and the relationship between angular diameter - distance. The Planck satellite, launched in 2009 by the European Space Agency, is dedicated to the study of CMB and the expected results of data analysis is the separation of signals contaminating the CMB, including the SZ effect. This paper presents the analysis of the distribution of SZ clusters in simulations of CMB maps produced by the Planck satellite. The clusters were produced from temperature profiles of the type "$\beta$ isothermal" and then combined with synthetic CMB maps generated in Healpix format, to test an algorithm of identification of the type "blind survey", that will be used in real maps. JADE ( emph Joint diagonalization of Approximate Eigenmatrices) is an algorithm based on Independent Component Analysis (ICA) and is effective in extracting non-Gaussian components. The results show that the JADE and the whole procedure adopted is effective in identifying the position and intensity of the SZ effect in each cluster, recovering about 92 \% of them to the case where the input maps are composed of linear combination of CMB, effect SZ, synchrotron emission, dust, free-free and instrumental noise, simulated using N$_{side}$ = 1024. This percentage varies with the N$_{side}$ used, noise characteristics and number of sources included in the maps analyzed.