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Chan Chi Wang = 宇宙微波背景輻射中之溫度與偏振各向不同性 / 陳志宏. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 94-98). / Text in English; abstracts in English and Chinese. / Chan Chi Wang = Yu zhou wei bo bei jing fu she zhong zhi wen du yu pian zhen ge xiang bu tong xing / Chen Zhihong. / Chapter 1 --- Overviewing modern cosmology --- p.1 / Chapter 1.1 --- Discoveries in Cosmology --- p.1 / Chapter 1.2 --- The Cosmological Model --- p.2 / Chapter 1.2.1 --- Cosmic Expansion --- p.3 / Chapter 1.2.2 --- The Metric and Friedmann Cosmology --- p.4 / Chapter 1.2.3 --- Thermodynamics of Matter and Radiation --- p.7 / Chapter 1.2.4 --- Timeline of the universe --- p.11 / Chapter 1.3 --- Formation of CMB and Its Anisotropics --- p.17 / Chapter 1.3.1 --- CMB --- p.17 / Chapter 1.3.2 --- CMB anisotropics --- p.18 / Chapter 1.4 --- Motivation and Thesis Outline --- p.21 / Chapter 2 --- The Recombination process --- p.23 / Chapter 2.1 --- The Saha approximation --- p.23 / Chapter 2.2 --- The Peebles recombination --- p.25 / Chapter 2.3 --- The RECFAST calculation --- p.28 / Chapter 3 --- The Boltzmann equations --- p.32 / Chapter 3.1 --- Boltzmann Equation for Photons --- p.33 / Chapter 3.1.1 --- Collision Term --- p.36 / Chapter 3.2 --- Boltzmann Equations for Matter --- p.37 / Chapter 3.2.1 --- Cold Dark Matter (CDM) --- p.37 / Chapter 3.2.2 --- Baryons --- p.38 / Chapter 3.3 --- Summary --- p.40 / Chapter 4 --- Formalism of CMB Anisotropies Calculation --- p.42 / Chapter 4.1 --- CMB Temperature Spectrum --- p.42 / Chapter 4.1.1 --- The Tight-coupling Solution --- p.43 / Chapter 4.1.2 --- Silk Damping --- p.45 / Chapter 4.1.3 --- The Free-Streaming Solution for fully decoupled cosmic fluid --- p.45 / Chapter 4.2 --- CMB Polarization Spectrum --- p.47 / Chapter 4.2.1 --- The E-mode and B-mode extractions --- p.48 / Chapter 4.3 --- The CMBFAST code --- p.50 / Chapter 4.4 --- Dependences on ionization history --- p.51 / Chapter 4.4.1 --- Recombination history --- p.53 / Chapter 4.4.2 --- Reionization history --- p.57 / Chapter 5 --- Softening of Equation of State during Recombination --- p.59 / Chapter 5.1 --- Recombination Revisited --- p.60 / Chapter 5.2 --- EOS softening by Recombination --- p.62 / Chapter 5.3 --- Numerical Results --- p.64 / Chapter 5.4 --- Summary and Discussions --- p.72 / Chapter 6 --- Time Varying Fundamental Constants --- p.74 / Chapter 6.1 --- Background --- p.74 / Chapter 6.1.1 --- Validity of time-varying fundamental constants --- p.76 / Chapter 6.1.2 --- The problem of units --- p.77 / Chapter 6.2 --- Theory --- p.78 / Chapter 6.3 --- Results --- p.79 / Chapter 6.3.1 --- Changing the electric charge --- p.80 / Chapter 6.3.2 --- Changing the electron mass --- p.82 / Chapter 6.3.3 --- Changing the cosmological constant --- p.85 / Chapter 6.3.4 --- Changing the speed of light --- p.87 / Chapter 6.4 --- Some concluding notes --- p.90 / Chapter 7 --- Conclusion --- p.92 / Bibliography --- p.94

Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics, August 2000. / Includes bibliographical references. Also available on the Internet.

Cosmology is now a precision science. The temperature anisotropies in the cosmic microwave background (CMB) have been exquisitely mapped by many experiments over the last decade. The Planck satellite was launched in 2009, observed the sky in temperature and polarisation, and released the nominal mission temperature data to the public in 2013. Planck has shed new light on CMB polarisation anisotropies and the polarisation signal from our own galaxy, and knowledge of the galactic emission forms a central part of this analysis presented in this thesis. I first introduce the background cosmology and review what we know about CMB temperature and polarisation anisotropies, including their mathematical formulation and representation on the sphere. I review our knowledge of the origin of galactic polarised foregrounds, particularly electron synchrotron and thermal dust emission. I then describe the generation of polarised CMB maps from an input cosmological model, and the generation of CMB polarised foregrounds using a variety of methods to create full-sky maps of the microwave sky at the Planck observing frequencies between 30 and 353 GHz. I develop a parametric fitting maximum-likelihood polarised component separation routine with correlated foreground parameters to extract the CMB and associated foregrounds to a high precision, and show that my method can reliably recover a primordial B-mode polarisation signal at r = 0.1 at multiple map resolutions. I then test the sky model against the full mission Planck data to examine how accurately the foregrounds are simulated, and find that along the galactic plane the simulations are accurate, but at high latitudes the agreement worsens. I also compare the polarisation morphology to that seen in the WMAP data and find a tension between Planck and WMAP. I present an analysis of the dx8 polarisation data in terms of polarised amplitudes and orientations, and investigate a variety of foreground separation routines to get a feel for the reliability of the data. Significant systematic issues are found and I conclude that in their current state, the polarisation data are not reliable enough for precise cosmology. Finally I develop a Fisher matrix analysis of the temperature power spectrum using the full mission covariance matrix to explore the parameter space around a CosmoMC simulation, and extract the principal components for different models. I use this to explore a strange oscillation in the power spectrum and conclude that it is a statistical fluke, a conclusion confirmed in a recent data release. I close by offering extensions to the work and a look into the future of the field.

The Planck cosmic microwave background temperature data are best fit with a Lambda CDM model that mildly contradicts constraints from other cosmological probes. The South Pole Telescope (SPT) 2540 deg(2) SPT-SZ survey offers measurements on sub-degree angular scales (multipoles 650 <= l <= 2500) with sufficient precision to use as an independent check of the Planck data. Here we build on the recent joint analysis of the SPT-SZ and Planck data in Hou et al. by comparing Lambda CDM parameter estimates using the temperature power spectrum from both data sets in the SPT-SZ survey region. We also restrict the multipole range used in parameter fitting to focus on modes measured well by both SPT and Planck, thereby greatly reducing sample variance as a driver of parameter differences and creating a stringent test for systematic errors. We find no evidence of systematic errors from these tests. When we expand the maximum multipole of SPT data used, we see low-significance shifts in the angular scale of the sound horizon and the physical baryon and cold dark matter densities, with a resulting trend to higher Hubble constant. When we compare SPT and Planck data on the SPT-SZ sky patch to Planck full-sky data but keep the multipole range restricted, we find differences in the parameters n(s) and A(s)e(-2 tau). We perform further checks, investigating instrumental effects and modeling assumptions, and we find no evidence that the effects investigated are responsible for any of the parameter shifts. Taken together, these tests reveal no evidence for systematic errors in SPT or Planck data in the overlapping sky coverage and multipole range and at most weak evidence for a breakdown of Lambda CDM or systematic errors influencing either the Planck data outside the SPT-SZ survey area or the SPT data at l > 2000.

A thesis submitted to the Faculty of Science, University of Witwatersrand, in the ful lment of the requirements for the degree of Doctor of Philosophy Johannesburg, South Africa, 2017. / According to the standard model of cosmology, the Universe has evolved from a thermal bath of elementary particles and photons towards one comprising of collapsed structures such as stars, galaxies and clusters of galaxies. The Cosmic Microwave Background (CMB) spectrum and its angular anisotropy across the sky contain information on the physical processes, matter distribution and evolution of the Universe across cosmic time. Primordial spectral distortions of the CMB and its anisotropy can be studied through the inverse comptonization process occuring in cosmic structures, known as the Sunyaev-Zel'dovich e ect (SZE). This present study demonstrates how the SZE can be used to obtain information on the 21 cm background produced between the Dark Ages (DA) and the Epoch of Reionization (EoR), on Non-Planckian (NP) modi cations of the CMB due to plasma frequency at the recombination epoch, and on the anisotropy of the CMB at cluster locations, through the study of the polarization of the SZE. To these aims, a full relativistic approach is employed, that allows us to calculate the spectra of the SZE and its polarization component with high precision, and allows to calculate it for any kind of electron population (thermal or nonthermal plasma), and for an input spectrum that can deviate from the standard black-body spectrum. The SZE-21cm, which is the comptonized spectrum of the modi ed CMB due to physical processes occuring during the DA and the EoR, is calculated for four models of the 21-cm background. A full spectral analysis of the signal is performed and the importance of relativistic e ects are highlighted. The results demonstrate that relativistic e ects are nonzero over the entire frequency spectrum and hence cannot be ignored, particularly for hot clusters. It is found that the amplitude of the SZE-21cm signal is of the order of Jy and is within the reach of the SKA instrument. Clusters with high temperature and optical depth are optimal targets to search for the SZE-21cm signal. The SKA can measure the signal in the frequency interval 75-90 MHz for clusters with temperature higher than 5 keV. Discerning the SZE-21cm from the standard SZE can be achieved using the SKA depending on the 21-cm background model for temperatures > 10 keV. Using CMB spectral data at both low and high frequencies, upper limits (206, 346 and 418 MHz at 1, 2, 3 con dence level) are placed on NP e ects associated with a non-zero plasma frequency at the recombination epoch. The SZENP is derived for a CMB spectrum modi ed due to plasma e ects using these upperlimits and a unique spectral feature is obtained. A peak occures at the plasma frequency in the SZENP independent of cluster parameters and the possibility of measuring the plasma frequency with the SKA and eVLA is shown. Plasma e ects are also investigated on the spectrum of the cosmological 21-cm background and it is found that such an e ect is important to consider when recovering the history of the Universe during these epochs. Polarization is a natural outcome of inverse Compton (IC) scattering and the anisotropy of the CMB plays a big role in the production of polarization in Comptonization process. The SZE polarization associated with the anisotropy of the CMB is derived in the full relativistic regime for any general electron distribution. The spectral shapes of the Stokes parameters induced by the IC scattering of the multipoles of the CMB for thermal and non-thermal electrons are derived, focusing mainly on the quadrupole and octupole which provide the largest possible detectable signals in cosmic structures. Our results demonstrate the implication of relativistic e ects, which become important for high temperature or non-thermal cluster environments. When relativistic e ects are accounted for, all the multipoles of the CMB are involved in the production of polarization. The octupole induced polarization spectrum reveals the existence of a cross-over frequency which is dependent on cluster parameters such as temperature, minimum momentum and spectral index. The possibilities to disentangle the quadrupole spectrum from the octupole one are discussed, which would allow the measurments of these multipoles at cluster locations. The generality of our approach allows us to calculate the SZE polarization spectra of the Bullet cluster using multifrequency SZE data in intensity and compare the results with the sensitivities of the SKA, ALMA, Millimetron and CORE++ instruments. Although the e ects that we studied here are small, however, they are still within the detection limits of the SKA, due to its very high sensitivity. Therefore, the SKA will play a big role in the study of cosmological radio backgrounds by providing high precision SZE data. / LG2018

The E and B EXperiment (EBEX) was a balloon-borne instrument designed to measure the polarization of the cosmic microwave background (CMB) while simultaneously characterizing Galactic dust emission. The instrument was based on a two-mirror ambient temperature Gregorian-Dragone telescope coupled with cooled refractive optics to a kilo-pixel array of transition edge sensor (TES) bolometeric detectors. To achieve sensitivity to both the CMB signal and Galactic foregrounds, EBEX observed in three signal bands centered on 150, 250, and 410 GHz. Polarimetry was achieved via a stationary wire-grid polarizer and a continuously rotating achromatic half-wave plate (HWP) based on a superconducting magnetic bearing (SMB). EBEX launched from McMurdo station, Antarctica on December 29, 2012 and collected ~ 1.3 TB of data during 11 days of observation. This thesis is presented in two Parts. Part I reviews the data analysis we performed to transform the raw EBEX data into maps of temperature and polarization sky signals, with a particular focus on post-flight pointing reconstruction; time stream cleaning and map making; the generation of model sky maps of the expected signal for each of the three EBEX signal bands; removal of the HWP-synchronous signal from the detector time streams; and our attempts to identify, characterize, and correct for non-linear detector responsivity. In Part II we present recent developments in instrumentation for the next generation of CMB polarimeters. The developments we describe, including advances in lumped-element kinetic inductance detector (LEKID) technology and the development of a hollow-shaft SMB-based motor for use in HWP polarimetry, were motivated in part by the design for a prospective ground-based CMB polarimeter based in Greenland.

by Su, Shi Chun = 宇宙微波背景各向異性的非高斯特性與旋轉宇宙的規範 / by 蘇士俊. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 78-83). / Abstracts in English and Chinese. / by Su, Shi Chun = Yu zhou wei bo bei jing ge xiang yi xing de fei Gaosi te xing yu xuan zhuan yu zhou de gui fan / by Su Shijun. / Chapter 1 --- Review of Cosmic Microwave Background Anisotropies --- p.1 / Chapter 1.1 --- Robertson-Walker metric --- p.1 / Chapter 1.2 --- Cosmological Perturbation --- p.4 / Chapter 1.2.1 --- Scalar-Vector-Tensor Decomposition --- p.6 / Chapter 1.2.2 --- Gauge Transformations --- p.8 / Chapter 1.2.3 --- Scalar Perturbation --- p.8 / Chapter 1.3 --- Sachs-Wolfe Effect --- p.9 / Chapter 1.4 --- Spectrum of CMB Anisotropies --- p.11 / Chapter 1.4.1 --- Rotation Transformation of Spherical Harmonics --- p.14 / Chapter 1.5 --- Contaminations of the CMBA --- p.16 / Chapter 1.5.1 --- The Internal Linear Combination Method --- p.17 / Chapter 2 --- Review of Models of Rotating Universe --- p.22 / Chapter 2.1 --- Godel's Model of a Rotating Universe --- p.23 / Chapter 2.2 --- Bianchi Models of a Rotating Universe --- p.24 / Chapter 2.3 --- Constraints on the Rotation of our Universe --- p.26 / Chapter 3 --- Study of Non-Gaussian Properties of the CMB Anisotropies --- p.31 / Chapter 3.1 --- Methodology --- p.32 / Chapter 3.2 --- Suspicious Anomalies against the IGH --- p.33 / Chapter 3.3 --- Verifications of the Suspicious Anomalies --- p.37 / Chapter 3.3.1 --- Different Cleaning Methods --- p.37 / Chapter 3.3.2 --- Effects of the Foreground Contaminations --- p.39 / Chapter 3.4 --- Further Study and Discussion --- p.52 / Chapter 3.5 --- Conclusions --- p.56 / Chapter 4 --- CMB Constraint on the Rotation of the Universe --- p.57 / Chapter 4.1 --- The Einstein Field Equations with Rotational Perturbations --- p.58 / Chapter 4.2 --- Analytic Solutions of the EFEs for the Rotating Universe --- p.63 / Chapter 4.3 --- The Sachs-Wolfe Effects up to Second-Order due to the Rotation --- p.65 / Chapter 4.4 --- Constraints on Our Model --- p.69 / Chapter 4.5 --- Discussion --- p.72 / Chapter 4.6 --- Conclusions --- p.75 / Chapter 5 --- Summary of the Thesis --- p.76 / Bibliography --- p.78

Chan, Wing Hang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 76-78). / Abstracts in English and Chinese. / Chan, Wing Hang. / Chapter 1 --- Review of Cosmology --- p.1 / Chapter 1.1 --- Background Evolution of Universe --- p.1 / Chapter 1.1.1 --- The Cosmological Principle --- p.1 / Chapter 1.1.2 --- The Non-static Universe --- p.3 / Chapter 1.1.3 --- Robertson-Walker metric --- p.3 / Chapter 1.1.4 --- Scale Factor and Cosmological Redshift --- p.3 / Chapter 1.1.5 --- Hubble Constant --- p.4 / Chapter 1.1.6 --- The Einstein Field Equations --- p.4 / Chapter 1.1.7 --- The Cosmological Constant --- p.6 / Chapter 1.1.8 --- Time Evolution --- p.6 / Chapter 1.1.9 --- Continuity Equation --- p.7 / Chapter 1.1.10 --- Conformal Distance --- p.8 / Chapter 1.2 --- Observational Data --- p.8 / Chapter 1.2.1 --- Type Ia Supernovae --- p.9 / Chapter 1.2.2 --- Cosmic Microwave Background --- p.9 / Chapter 2 --- Review of Dark Energy Models --- p.11 / Chapter 2.1 --- The Cosmological Constant --- p.11 / Chapter 2.2 --- Quintessence --- p.11 / Chapter 2.3 --- Extra Dimension Models --- p.12 / Chapter 2.3.1 --- Kaluza-Klein --- p.12 / Chapter 2.3.2 --- Generalized Homogeneous and Isotropic Extra Dimensions --- p.12 / Chapter 3 --- Review of CMB and Type Ia Supernovae --- p.17 / Chapter 3.1 --- Type Ia Supernovae --- p.17 / Chapter 3.1.1 --- Comparison of cosmological models with recent SNIa data --- p.18 / Chapter 3.2 --- Cosmic Microwave Background Radiation --- p.18 / Chapter 3.2.1 --- Power Spectrum of CMBA --- p.18 / Chapter 3.2.2 --- Photon Baryon Oscillation --- p.21 / Chapter 3.2.3 --- Acoustic Peaks --- p.23 / Chapter 3.2.4 --- Matter Perturbation --- p.24 / Chapter 3.2.5 --- Baryon Loading --- p.24 / Chapter 3.2.6 --- Photons Driving --- p.25 / Chapter 3.2.7 --- Initial Conditions --- p.25 / Chapter 3.2.8 --- Reionization --- p.26 / Chapter 3.2.9 --- The Vanilla ACDM Model --- p.26 / Chapter 3.2.10 --- Summary of CMBA --- p.26 / Chapter 4 --- Constraining Dark Energy Models --- p.27 / Chapter 4.1 --- Constraining Dark Energy Density Using SN Ia data --- p.27 / Chapter 4.1.1 --- Direct Calculation of Dark Energy Density --- p.27 / Chapter 4.2 --- Constraining Dark Energy Density Using CMB data --- p.31 / Chapter 4.2.1 --- Dark Energy Evolution for time varying EOS --- p.31 / Chapter 4.2.2 --- Dark Energy Density Perturbation --- p.32 / Chapter 4.2.3 --- Parameterization of Time Varying Dark Energy --- p.32 / Chapter 4.2.4 --- Effect of Dark Energy Density on CMBA power spectrum --- p.33 / Chapter 4.2.5 --- Limitations and Difficulties Constraining Dark Energy Equation of State --- p.41 / Chapter 4.2.6 --- Constraining the Evolution of Dark Energy Density with a polynomial model --- p.54 / Chapter 4.2.7 --- Constraining Evolution of Dark Energy Density with Gaussian-type EOS --- p.59 / Chapter 4.2.8 --- Constraining Evolution of Dark Energy Step Function EOS with CMB Acoustic Peaks --- p.66 / Chapter 5 --- Summary --- p.73 / Bibliography --- p.76

Thesis (Ph. D.)--University of Chicago, Department of Astronomy and Astrophysics, 2001. / Includes bibliographical references. Also available on the Internet.