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published_or_final_version / Architecture / Master / Master of Architecture

The European Space Agency's Herschel Space Observatory is comprised of three cryogenically cooled instruments commissioned to explore the far infrared/submillimetre universe. The Spectral and Photometric Imaging REceiver (SPIRE) is one of Herschel's instruments and consists of a three band imaging photometer and a two band imaging spectrometer. Canada is involved in the SPIRE project through provision of instrument development hardware and software, mission flight software, and support personnel. This thesis discusses Fourier transform spectroscopy (FTS) and FTS data processing. A detailed discussion is included on FTS phase correction, with results presented from the optimization of an enhanced Forman phase correction routine developed for this work. This thesis discusses the design, verification, and use of the hardware and software provided by Dr. Naylor's group as it relates to SPIRE verification testing. Results of the photometer characterization are presented. The current status of SPIRE and its future schedule is also discussed. / xvii, 239 leaves : ill. (some col.) ; 28 cm.

This thesis addresses high performance computing in Adaptive Optics (AO) simulation and the development and demonstration of a prototype AO instrument for future Extremely Large Telescopes (ELTs). Adaptive Optics systems are used on astronomical telescopes for correcting the blurring effects of atmospheric turbulence on incoming starlight, improving image quality to that of the diffraction limit of the telescope. Extremely Large Telescopes will have primary mirror diameters in the 20 - 40 m range, driving the need for technology development in two key areas, among others: 1) adaptive optics simulation, and 2) wide field adaptive optics (WFAO). The Linear Adaptive Optics Simulator (LAOS) is at the forefront of adaptive optics simulation, opening up the capability to simulate ELTs with integrated AO systems on a single computer. This is computationally expensive and time consuming, and thus simulator performance is very important and can determine the feasibility of simulating such systems at all. Efforts were made to improve the existing LAOS performance and bring a larger range of problem sizes and AO instrument concepts including WFAO into the realm of possibility. WFAO will take advantage of the larger light collection and spatial resolution capabilities of ELTs. One WFAO instrument approach that addresses this is Multi-Object Adaptive Optics (MOAO), which will provide localized correction around a number (5 - 40) of selected science objects spread around the field of view, enabling extragalactic studies otherwise very costly to implement with other WFAO techniques. However, there are several risks that need to be retired. Many elements of an MOAO system, such as the use of atmospheric tomography, MEMS mirrors, and woofer-tweeter control have all been demonstrated to work in different lab settings and are included in advanced instrument concepts. Open loop control, however, is perhaps the greatest risk to MOAO, introducing unique requirements on the AO system. The Victoria Open Loop Testbed (VOLT) serves as a demonstration of open loop control – both on-sky at the Dominion Astrophysical Observatory's 1.2 m telescope and in the lab – to facilitate the future development of MOAO. Our goal was to demonstrate open loop control with a simple on-axis natural guide star testbed.

Although the Sloan Digital Sky Survey (SDSS) has compiled an unprecedented amount of photometric data on stellar populations in the Milky Way, it is not presently possible to accurately and consistently interpret these data due to the lack of precise fiducial stellar sequences and color-temperature relations for the new 'u'g'r'i'z' photo-metric system. In order to address these deficiencies, this study describes an extensive observational project that has obtained high-quality and homogeneous photometry for a number of different Galactic star clusters spanning a wide range in meta.llicity (-2.5 ≤ [Fe/H] ≤ +0.3), as observed in the u'g'r'i'z' passbands with the MegaCam wide-field imager on the Canada-France-Hawaii Telescope. By employing these purest of stellar populations, fiducial sequences have been defined from color-magnitude diagrams (CMDs) that. extend from the tip of the RGB down to approximately 4 magnitudes below the turnoff points: these have been accurately calibrated to the standard u'g'r'i'z` system via a set of secondary photometric standards located within these same clusters. Consequently, they can serve as a valuable set of empirical fiducials for the interpretation of stellar populations data in the system, as well as calibrators for the transformation of stellar isochrones to the u'g'r'i'z' bandpasses. In fact. when a new grid of theoretical color-Teff relations and bolometric corrections for the system is computed from Kurucz model atmospheres and employed to translate isochrones to the observed planes, generally very good and consistent fits to the CMDs of the metal-poor ([Fe/H] <0.0) globular clusters M 92, M 13, and M 71 are found, once reasonable estimates of the cluster parameters are assumed (the only obvious discrepancy is a shift of ~ 0.01 - 0.03 mag between the predicted and observed giant branches when the models are fitted to the main sequences). More-over, the same isochrone fits are entirely consistent with those inferred from cluster observations in other photometric systems - notably, the BV(RI) , and uvby systems. At the metal-rich end ([Fe/H] ≥ 0.0), however. these transformations fail to match the observed loci of cool, main-sequence stars (Teff ≤ 5000K) in the open clusters M 67 and NGC 6791. An exploration into possible causes of these discrepancies is provided.

Thesis (Ph. D.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 123-129).

Apresentamos o planejamento, desenvolvimento e aplicação de uma proposta de curso de extensão em Astronomia, dividido em módulos e oferecido a estudantes de ensino médio visando a aprendizagem da Astronomia e das ciências afins a partir da observação rudimentar e da imagem astronômica. A confecção do material didático destinado ao curso e a elaboração das aulas tiveram por base a teoria da mediação de Lev Vygotsky e a epistemologia de Stephen Toulmin. O projeto incluiu a realização de uma experiência piloto, da qual foram extraídos subsídios para seu aperfeiçoamento. Apresentamos aqui o relato desta experiência e de seus resultados, bem como o desenvolvimento e aplicação de uma segunda versão do curso e dos resultados obtidos. Como instrumentos de avaliação foram utilizados pré e póstestes idênticos. Da análise destes instrumentos, verificamos um aumento no número absoluto de acertos de cerca de 55% na avaliação, com relação à avaliação prévia, na segunda implementação do curso. Esse resultado, conjuntamente com a análise qualitativa dos comentários feitos pelos estudantes concluiu-se que a utilização da imagem astronômica e a observação rudimentar com fins didáticos é viável e frutífera. Como produto educacional desta dissertação confeccionamos um CD com o conteúdo das aulas, que acompanha guias ao professor que queira replicar a experiência. / We present an outreach course in Astronomy and related sciences at high school level, describing its planning, development and application. The course is modulated and uses elementary astronomical observation and images as its basic learning tools. The didatic material for the project and the lecture grid are based on Lev Vygotsky mediation theory and the epistemology be Stephen Toulmin. The project involved an initial test course, from which we extracted subsidies for its improvement. We describe this initial experience and its results. We also describe the application of the second version of the course. Identical pre and post course tests we used to assess the impact of both versions and led to a final 55% improvement in the rate of correct answers, on the second version of the course. This result, along with the qualitative analysis of the comments made by the students, shows the importance of astronomical images and observations as teaching tools. Finally, the course is detailed out in a CD containing not only the material developed for the lectures, but also a guide to other teachers who wish to apply it in their classes.

Since the discovery of 51 Pegasi b in 1995, continued observations have indirectly identified over 110 planetary objects. These Jupiter-mass objects cause their host star to "wobble" slightly about the common centre-of-mass of the system, which is detectable as radial motion in high-precision Doppler spectroscopy. Of the known planets, approximately 20% are found to orbit within 0.1 AU of the star, whilst the transit of HD209458 has inferred the gas-giant nature of these close-in extrasolar giant planets (CEGPs). The discovery of CEGPs has produced a wave of speculative theory as to the exact nature of these objects, and how they came to exist so close to their parent star. Our spectroscopic technique provides a method of achieving the direct detection of a CEGP atmosphere, the results of which will allow us to test emerging models that aim to predict the atmospheric nature of CEGPs and may provide additional information on the orbital inclination and mass of the planet. We start with a historical review of the field of extrasolar planets, followed by an introduction to the fundamental concepts which underpin the reflection of starlight from a planet's surface. We then investigate the prospects of detecting such a reflection, before detailing the technique we have devised and applied here to two known CEGP hosts. In the first instance, r Bootis, we combined observations at the 4.2-m William Herschel telescope in 1998, 1999 and 2000. The dataset comprised 893 high-resolution échelle spectra with a total integration time of 75hr 32min spanning 17 nights. We establish an upper limit on the planet's geometric albedo p < 0.39 (at the 99.9% significance level) at the most probable orbital inclination i ~ 36 deg, assuming a grey albedo, a Venus-like phase function and a planetary radius Rp - 1.2RJup. Although a weak candidate signal appears near to the most probable radial velocity amplitude, its statistical significance is insufficient for us to claim a detection with any confidence. In the second instance, HD75289, 4 nights of VLT(UT2)/UVES observations were secured in 2003 Jan, yielding 684 high-resolution spectra with a total integration time of 26 hours. We establish an upper limit on the planet's geometric albedo p < 0.12 (to the 99.9% significance level) at the most probable orbital inclination i ~/= 60 deg, assuming a grey albedo, a Venus-like phase function and a planetary radius Rp = 1.6RJup. In both cases, we are able to rule out some combinations of the predicted planetary radius and atmospheric albedo models with high, reflective cloud decks.

Apresentamos o planejamento, desenvolvimento e aplicação de uma proposta de curso de extensão em Astronomia, dividido em módulos e oferecido a estudantes de ensino médio visando a aprendizagem da Astronomia e das ciências afins a partir da observação rudimentar e da imagem astronômica. A confecção do material didático destinado ao curso e a elaboração das aulas tiveram por base a teoria da mediação de Lev Vygotsky e a epistemologia de Stephen Toulmin. O projeto incluiu a realização de uma experiência piloto, da qual foram extraídos subsídios para seu aperfeiçoamento. Apresentamos aqui o relato desta experiência e de seus resultados, bem como o desenvolvimento e aplicação de uma segunda versão do curso e dos resultados obtidos. Como instrumentos de avaliação foram utilizados pré e póstestes idênticos. Da análise destes instrumentos, verificamos um aumento no número absoluto de acertos de cerca de 55% na avaliação, com relação à avaliação prévia, na segunda implementação do curso. Esse resultado, conjuntamente com a análise qualitativa dos comentários feitos pelos estudantes concluiu-se que a utilização da imagem astronômica e a observação rudimentar com fins didáticos é viável e frutífera. Como produto educacional desta dissertação confeccionamos um CD com o conteúdo das aulas, que acompanha guias ao professor que queira replicar a experiência. / We present an outreach course in Astronomy and related sciences at high school level, describing its planning, development and application. The course is modulated and uses elementary astronomical observation and images as its basic learning tools. The didatic material for the project and the lecture grid are based on Lev Vygotsky mediation theory and the epistemology be Stephen Toulmin. The project involved an initial test course, from which we extracted subsidies for its improvement. We describe this initial experience and its results. We also describe the application of the second version of the course. Identical pre and post course tests we used to assess the impact of both versions and led to a final 55% improvement in the rate of correct answers, on the second version of the course. This result, along with the qualitative analysis of the comments made by the students, shows the importance of astronomical images and observations as teaching tools. Finally, the course is detailed out in a CD containing not only the material developed for the lectures, but also a guide to other teachers who wish to apply it in their classes.

Considerando a forte relação entre a Astronomia e a Física, a pesquisa apresentada propõe focalizar uma atividade de ensino que, partindo da observação do céu, com motivação para compreendê-lo, indo além da admiração e do deslumbramento, leve à elaboração de conceitos da Física escolar. A pesquisa trata de investigar uma forma de desenvolver o conceito de energia partindo de uma observação astronômica, onde os aprendizes são participantes ativos no processo da sua aprendizagem. Foi desenvolvida uma sequência didática e aplicada a alunos do Ensino Médio de uma escola pública de São Paulo. O objetivo era motivar os alunos a observar um fenômeno celeste, as crateras lunares, para construir o conceito de energia mecânica, num processo com as etapas de: observação, obtenção de dados pertinentes e adequados, levantamento de hipóteses e verificação num experimento controlado no laboratório escolar. Todas as atividades foram registradas em áudio ou vídeo e, com base nas transcrições, foi realizada uma análise textual discursiva. A análise permitiu qualificar as observações sob diferentes aspectos, bem como revelar as concepções expressas na tentativa de modelar, no laboratório escolar, uma possível causa das crateras observadas. Em todo o trabalho foi notável o papel fundamental do professor como mediador; a atenção para acompanhar a argumentação dos alunos e orientar as atividades parece ter garantido resultados de aprendizagem. A teoria de Vigotski foi considerada para interpretar os resultados sobre a construção de conceitos. Como resultados foram obtidas categorias sobre como se dão as observações realizadas pelos alunos, saindo de uma Observação Primária, evoluindo até uma Observação Qualificada. E também quais as relações que se estabelecem ao investigar um problema para que o conceito de energia mecânica crie significado para o aluno, Relações entre as grandezas e o conceito, até a Relação de Terceiro Grau, entre conceito e fenômeno. / In view of the strong relationship between Astronomy and Physics the proposed research aims to focus on a teaching activity that starts from the sky observation with an understanding motivation that lies beyond admiration and bewilderment and that may lead to the elaboration of school Physics concepts. The research deals with the investigation of a way of developping the concept of energy, starting from astronomical observations where students take active part in their learning process. A didactic sequence was elaborated and applied to secondary school students at a São Paulo public school. The objective was to motivate students to observe a celestial phenomenom, namely lunar craters, in order to build up the concept of mechanical energy in a process with the following steps: observation, obtention of related and adequate data, possible hypothesis and verification with a school laboratory controlled experiment. All activities were recorded in audio or video and with the aid of transcriptions a textual discursive analysis was effected. This analysis enabled a qualification of observations under several points of view as well as disclosing conceptions that were expressed in an atempt to model, in the school laboratory, a possible cause for the observed craters. The role played by the teacher during the whole process was essential as a moderator; his attention to follow the students argumentation and drive activities seems to have secured learning results. Vigotski theory was considered for interpreting results respect to construction of concepts. As results were obtained classes of observations made by the students, leaving a Primary Observation, evolving into a Qualified Observation. And what are the relationships that are established to investigate a problem that the mechanical energy concept create meaning to the student, relations between quantities and the concept, to the third degree of relationship, between concept and phenomenon.