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study of cosmic microwave background anisotropies =: 宇宙微波背景輻射不均性之硏究. / 宇宙微波背景輻射不均性之硏究 / A study of cosmic microwave background anisotropies =: Yu zhou wei bo bei jing fu she bu jun xing zhi yan jiu. / Yu zhou wei bo bei jing fu she bu jun xing zhi yan jiuJanuary 2002 (has links)
Leung Po Kin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 86-91). / Text in English; abstracts in English and Chinese. / Leung Po Kin. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The expanding universe --- p.1 / Chapter 1.2 --- Brief Thermal History of The Universe --- p.5 / Chapter 1.3 --- Cosmic Microwave background --- p.7 / Chapter 1.3.1 --- CMB Anisotropy --- p.8 / Chapter 1.4 --- Structure Formation --- p.9 / Chapter 1.5 --- Current Observation --- p.9 / Chapter 2 --- Recombination --- p.11 / Chapter 2.1 --- Ionization Fraction --- p.12 / Chapter 2.1.1 --- Saha Equations --- p.12 / Chapter 2.1.2 --- Rate Equation --- p.13 / Chapter 2.2 --- Matter Temperature --- p.16 / Chapter 3 --- Review of Structure Formation Theory --- p.20 / Chapter 3.1 --- Basic Ideas --- p.21 / Chapter 3.1.1 --- Power Spectrum --- p.22 / Chapter 3.2 --- Equations that govern Structure Formation --- p.24 / Chapter 3.2.1 --- Newtonian theory --- p.24 / Chapter 3.2.2 --- Boltzmann equation --- p.25 / Chapter 4 --- Review of CMB Anisotropies Theory --- p.28 / Chapter 4.1 --- CMB Physics --- p.29 / Chapter 4.1.1 --- Tight Coupling Limit --- p.29 / Chapter 4.1.2 --- Diffusion Damping and Free Streaming --- p.30 / Chapter 4.2 --- Numerical Method --- p.31 / Chapter 4.2.1 --- Solving Systems of Boltzmann Equations --- p.31 / Chapter 4.2.2 --- Line of Sight Integration --- p.32 / Chapter 5 --- Effect of recombination --- p.35 / Chapter 5.1 --- Effect of Recombination --- p.35 / Chapter 5.1.1 --- Cosmic Reheating and Softening --- p.35 / Chapter 5.1.2 --- Release of Heat --- p.36 / Chapter 5.2 --- Effect on expansion of the universe --- p.36 / Chapter 5.3 --- Effect on ionization fraction --- p.38 / Chapter 5.4 --- Recombination softening --- p.38 / Chapter 5.4.1 --- Results --- p.40 / Chapter 5.4.2 --- Discussion and Summary --- p.44 / Chapter 6 --- Change of Fundamental Constants --- p.53 / Chapter 6.1 --- Change of fundamental constants --- p.54 / Chapter 6.1.1 --- Some conceptual problems --- p.55 / Chapter 6.1.2 --- Effect on CMB --- p.56 / Chapter 6.2 --- Friedmann equations --- p.57 / Chapter 6.3 --- Baryon temperature --- p.64 / Chapter 6.4 --- Ionization fraction --- p.66 / Chapter 6.4.1 --- Better treatment --- p.67 / Chapter 6.4.2 --- Numerical calculation --- p.70 / Chapter 6.5 --- Effect on different physics of formation of CMB --- p.77 / Chapter 6.5.1 --- Properties of photon-baryon fluid --- p.78 / Chapter 6.5.2 --- Diffusion damping --- p.80 / Chapter 6.6 --- Conclusion --- p.84 / Bibliography --- p.86 / Chapter A --- Boltzmann equations --- p.92 / Chapter B --- Comparison of the energy terms --- p.95 / Chapter C --- Discussion of the analytic method for CMB temperature spec- trum --- p.99
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Confrontations of non-standard physics models with cosmic microwave background data. / 宇宙微波背景幅射數據對非標準物理的規範 / Confrontations of non-standard physics models with cosmic microwave background data. / Yu zhou wei bo bei jing fu she shu ju dui fei biao zhun wu li de gui fanJanuary 2007 (has links)
Chan, Kwan Chuen = 宇宙微波背景幅射數據對非標準物理的規範 / 陳坤全. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 95-101). / Text in English, abstracts in English and Chinese. / Chan, Kwan Chuen = Yu zhou wei bo bei jing fu she shu ju dui fei biao zhun wu li de gui fan / Chen Kunquan. / Chapter 1 --- Overview of Cosmology --- p.1 / Chapter 1.1 --- Friedmann-Robertson-Walker Universe --- p.1 / Chapter 1.2 --- The Hubble Diagram and Type Ia Supernovae --- p.3 / Chapter 1.3 --- Big Bang Nucleosynthesis --- p.5 / Chapter 1.4 --- Cosmic Microwave Background --- p.8 / Chapter 1.5 --- Matter Power Spectrum and Galaxy Surveys --- p.10 / Chapter 1.6 --- The Energy Density Budget of the Universe and Outlook --- p.13 / Chapter 2 --- Review of CMB Physics --- p.17 / Chapter 2.1 --- Main Physics of the CMB Power Spectra --- p.17 / Chapter 2.1.1 --- Photon-Baryon Fluid --- p.17 / Chapter 2.1.2 --- Initial Conditions --- p.20 / Chapter 2.1.3 --- Acoustic Peaks --- p.22 / Chapter 2.1.4 --- Baryons in Action --- p.23 / Chapter 2.1.5 --- Damping --- p.24 / Chapter 2.1.6 --- Polarization --- p.25 / Chapter 2.2 --- Computation of CMB Power Spectrum --- p.26 / Chapter 3 --- Constraints on Variation of the Gravitational Constant by CMB --- p.30 / Chapter 3.1 --- Current Constraints on G and Theoretical Motivations --- p.31 / Chapter 3.2 --- Parametrization of G --- p.32 / Chapter 3.3 --- Effect of Variation of G on the CMB Temperature and Polarization Power Spectra --- p.34 / Chapter 3.4 --- Constraining G by MCMC and Discussions --- p.40 / Chapter 3.5 --- Conclusion --- p.45 / Chapter 4 --- Constraints on f(R) Cosmology in the Palatini Formalism --- p.47 / Chapter 4.1 --- Introduction --- p.48 / Chapter 4.2 --- Field Equations in Theories of Palatini - f(R) Gravity --- p.50 / Chapter 4.2.1 --- General Theory of f(R) Gravity in the Palatini Approach --- p.50 / Chapter 4.2.2 --- The Perturbation Equations --- p.52 / Chapter 4.3 --- Numerical Results and Cosmological Constraints --- p.56 / Chapter 4.4 --- Discussion and Conclusion --- p.62 / Chapter 5 --- CMB Constraint on Radion Evolution in the Brane World Scenario --- p.65 / Chapter 5.1 --- Introduction --- p.66 / Chapter 5.2 --- Dimensional Reduction and Low Energy Effective Actions --- p.68 / Chapter 5.3 --- Numerical Constraints on the Evolution of the Radion --- p.72 / Chapter 5.3.1 --- Effects of Variation of Higgs VEV on CMB Power Spectra --- p.72 / Chapter 5.3.2 --- Numerical Constraints on the Higgs VEV and Radion by CMB --- p.75 / Chapter 5.4 --- Conclusion --- p.80 / Chapter 6 --- Summary of the Thesis --- p.81 / Chapter A --- Markov Chain Monte Carlo Method --- p.84 / Chapter A.1 --- Basic Theory of MCMC --- p.84 / Chapter A.2 --- The Metropolis-Hastings Algorithm --- p.86 / Chapter A.3 --- Convergence Diagnostics --- p.87 / Chapter B --- Forecast by Fisher Matrix --- p.89 / Chapter C --- Modified Equations in RECFAST with Variation me --- p.92 / Bibliography --- p.95
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Design and testing of tuning algorithms for the E and B EXperiment (EBEX)MacDermid, Kevin. January 2008 (has links)
Detection of B-mode polarization from the cosmic microwave background would provide compelling evidence for the inflationary paradigm and has thus become a principal goal for experimental cosmologists during the last 5-10 years. A number of high sensitivity experiments have been developed and many are under construction, including the E and B EXperiment (EBEX), a balloon-borne experiment scheduled to take data in 2010. The design of EBEX is presented here, including the scientific motivation for the experiment, and an overview of all its components, with particular attention paid to the read out electronics for its array of over 1300 biometries detectors. In the read out of such a large array of bolometers, which must be kept at ∼250mK, running many signals down the same wire (i.e. multiplexing) is vital. The digital frequency multiplexing (dfmux) electronics designed and tested at McGill addresses this as well as providing the control required to tune the bolometers and super conducting quantum interference devices (SQUIDs) used in readout. How these electronics accomplish both of these goals is described with an in-depth description of the recently designed tuning algorithms required to take the detectors from initialization to fully-operational. Finally, some tests of the readout system on cold bolometers in a test cryostat are presented. These measurements are encouraging with 98% success rate of automated tuning on a test sample of 47 bolometers. Improvements to achieve a 100% success rate have been proposed and will be implemented for the upcoming integration of the bolometer camera with the telescope in November 2008. A test-flight for the experiment is planned for spring 2009, and the science flight for 2010 from Antarctica.
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Small-scale secondary anisotropies in the Cosmic Microwave BackgroundDudley, Jonathan, 1982- January 2008 (has links)
One of the main harbingers of the modern age of precision cosmology, the Cosmic Microwave Background (CMB) has proven itself to be a veritable trove of cosmological information. With the aid of experiments such as the WMAP satellite, precision measurements of the CMB anisotropy spectra are now being made. / This work will first explore the physics of the Vishniac effect, a small-scale CMB temperature anisotropy created by the Compton scattering of CMB photons by free electrons caught in a line-of-sight bulk flow. The Vishniac effect arises due to a density enhancement in the electrons caused by gravitational potentials in both the linear and nonlinear regimes and contributes significant power to the CMB temperature anisotropy power spectrum on small scales. This effect is strongly dependent upon cosmology and as such this dependence is investigated for all experimentally-allowed values of the fundamental cosmological parameters. This analysis is performed for both the linear Vishniac effect as well as its nonlinear extension. Following this analysis a fitting function, capable of predicting the power generated by the Vishniac effect over a range of scales for any allowed cosmology, is investigated. This function proves to be an accurate and efficient way of computing the Vishniac effect for any input cosmology. / The next small-scale phenomenon to be explored is the small-scale CMB polarization anisotropies generated by Thomson scattering of the local photon quadrupole anisotropy during reionization. The underlying physics behind this effect are studied along with the observational information it potentially contains. Observational data of the remote quadrupole is capable of improving constraints in the CMB temperature anisotropy spectrum on scales of ℓ ∼ 11 as well as offering information concerning the reconstruction of the primordial density perturbations on gigaparsec scales in our local universe.
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Cosmic reionisation and the primordial fluctuations in the UniverseVan Engelen, Alexander. January 2007 (has links)
We investigate the effect of allowing freedom in the primordial power spectrum of curvature perturbations upon the measurement of other cosmological parameters, in particular the Thomson optical depth due to cosmic reionisation which is present in cosmic microwave background (CMB) observations. We find that the constraint on the optical depth from Wilkinson Microwave Anisotropy Probe (WMAP) data broadens by approximately 10% upon allowing spectral freedom on large scales, and by a slightly larger factor when considering data from future experiments with lower noise in measurements of CMB polarisation. We also present a reconstruction of the primordial power spectrum on the largest scales from WMAP, which is jointly obtained from this analysis.
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Data reduction and analysis of the Python V cosmic microwave background anisotropy experiment /Coble, Kimberly Ann. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics. / Includes bibliographical references. Also available on the Internet.
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Cosmic reionisation and the primordial fluctuations in the UniverseVan Engelen, Alexander. January 2007 (has links)
No description available.
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Small-scale secondary anisotropies in the Cosmic Microwave BackgroundDudley, Jonathan, 1982- January 2008 (has links)
No description available.
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Design and testing of tuning algorithms for the E and B EXperiment (EBEX)MacDermid, Kevin January 2008 (has links)
No description available.
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Topics in cosmology. / 宇宙學中的題目 / Topics in cosmology. / Yu zhou xue zhong de ti muJanuary 2006 (has links)
Cheung Kai Chung Mars = 宇宙學中的題目 / 張啓聰. / Thesis submitted in: September 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 93-95). / Text in English; abstracts in English and Chinese. / Cheung Kai Chung Mars = Yu zhou xue zhong de ti mu / Zhang Qicong. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- "Hubble's Law, the cosmic scale factor and redshift" --- p.1 / Chapter 1.2 --- The Big Bang Model and Cosmic Microwave Background --- p.3 / Chapter 1.3 --- An overview of the universe --- p.4 / Chapter 1.4 --- Current Observation Results and Motivation --- p.6 / Chapter 1.5 --- Review of CMB calculation --- p.7 / Chapter 1.5.1 --- Friedmann Cosmologies --- p.8 / Chapter 1.5.2 --- The Perturbed Robertson-Walker Metric --- p.10 / Chapter 1.5.3 --- Boltzmann Equations --- p.13 / Chapter 1.5.4 --- Perturbative Einstein Equations --- p.16 / Chapter 2 --- Ionization History of The Universe --- p.18 / Chapter 2.1 --- Saha equation --- p.18 / Chapter 2.2 --- Peebles recombination --- p.19 / Chapter 2.3 --- RECFAST --- p.20 / Chapter 3 --- CMB Anisotropics --- p.22 / Chapter 3.1 --- The CMBA spectra --- p.23 / Chapter 3.1.1 --- Tight Coupling Limit --- p.23 / Chapter 3.1.2 --- Free Streaming --- p.25 / Chapter 3.1.3 --- The Anisotropy Spectrum --- p.27 / Chapter 3.1.4 --- CMBFAST --- p.28 / Chapter 4 --- Variation of Fundamental Constant and CMBA spectra --- p.30 / Chapter 4.1 --- The problem of units --- p.31 / Chapter 4.2 --- Modification of CMBFAST and conversion of units --- p.32 / Chapter 4.3 --- The constraints of varying constants using CMBA spectra --- p.35 / Chapter 4.4 --- Physics involved and variation of the spectra --- p.36 / Chapter 4.4.1 --- Effect of Recombination --- p.36 / Chapter 4.4.2 --- Variation of hP --- p.38 / Chapter 4.4.3 --- Variations of e and me --- p.41 / Chapter 4.4.4 --- Variations of g and c --- p.48 / Chapter 4.4.5 --- Constraints on the constants --- p.57 / Chapter 5 --- MCMC and CMBA Spectra --- p.59 / Chapter 5.1 --- Method --- p.60 / Chapter 5.1.1 --- Algorithm --- p.60 / Chapter 5.1.2 --- Check of Convergency --- p.61 / Chapter 5.2 --- Likelihood function --- p.62 / Chapter 5.3 --- Results --- p.66 / Chapter 5.3.1 --- MCMC investigation of varying α in the temperature spectrum --- p.67 / Chapter 5.3.2 --- MCMC investigation of varying α in the polarization spectrum --- p.69 / Chapter 5.3.3 --- MCMC investigation of varying α and cosmological parameters --- p.71 / Chapter 5.3.4 --- Summary --- p.73 / Chapter 6 --- Extra Dimensions and Cosmology --- p.74 / Chapter 6.1 --- A review of KK cosmology --- p.74 / Chapter 6.2 --- Non-flat extra dimension universe --- p.80 / Chapter 6.2.1 --- Close Extra Dimensions and Flat Usual Dimensions --- p.83 / Chapter 6.2.2 --- Open Extra Dimensions and Flat Usual Dimensions --- p.87 / Chapter 6.2.3 --- Summary: Possibility of Extra Dimension(s) --- p.91 / Bibliography --- p.93
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