We measure the cross-correlation between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg(2) of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of z(med) similar to 0.7, while the CMB lensing kernel is broad and peaks at z similar to 2. The resulting cross-correlation is maximally sensitive to mass fluctuations at z similar to 0.44. Assuming the Planck 2015 best-fitting cosmology, the amplitude of the DESxSPT cross-power is found to be A(SPT) = 0.88 +/- 0.30 and that from DESxPlanck to be A(Planck) = 0.86 +/- 0.39, where A = 1 corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of 2.9 sigma and 2.2 sigma, respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photo-z uncertainty and CMB lensing systematics. We calculate a value of A = 1.08 +/- 0.36 for DESxSPT when we correct the observations with a simple intrinsic alignment model. With three measurements of this cross-correlation now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of cross-correlation. We provide forecasts for the expected signal-to-noise ratio of the combination of the five-year DES survey and SPT-3G.

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.

Lau, King = 普朗克衛星測量對純量-張量比例的規範 / 劉荊. / Thesis M.Phil. Chinese University of Hong Kong 2013. / Includes bibliographical references (leaves 83-89). / Abstracts also in Chinese. / Title from PDF title page (viewed on 15, September, 2016). / Lau, King = Pulangke wei xing ce liang dui chun liang-zhang liang bi li de gui fan / Liu Jing.

This thesis investigates weak lensing (WL) of galaxies and the cosmic microwave back- ground (CMB) in the nonlinear regime. WL describes the effect of bending of background light rays by foreground matter (“lens”). It is sensitive to the large scale structure of the universe, and hence is a promising method to answer some unsolved fundamental questions in physics, such as the nature of dark energy and the total mass of neutrinos. WL datasets of unprecedented precision will come on-line in the early 2020s. This presents an exciting yet challenging task for the WL community: how do we extract the maximum amount of information from lensing observables, while minimizing the impact of systematics? This work attempts to answer this question by studying non-Gaussian statistics. Traditionally, WL data are analyzed using second-order statistics, which capture all the cosmological information if the density field is Gaussian. However, the small-scale density fluctuations are strongly non-Gaussian and can be highly sensitive to cosmology. Thus we need higher order (non-Gaussian) statistics to utilize these features in the nonlinear regime. In this thesis, we study the constraining power on cosmology and relevant systematics of non-Gaussian statistics, with a focus on convergence peaks. We present the first cosmological constraints using peak counts of the CFHTLenS survey. We also quantify the impact of magnification and size bias, one type of lensing systematics, on the lensing power spectrum and peaks. Finally, going beyond galaxy lensing, we cross-correlate Planck CMB lensing maps with CFHTLenS galaxy lensing maps, to investigate various WL systematics.

The E and B EXperiment (EBEX) is a pointed balloon-borne telescope designed to measure the polarization of the cosmic microwave background (CMB) as well as that from Galactic dust. The instrument is equipped with a 1.5 meter aperture Gregorian-Dragone telescope, providing an 8' beam at three frequency bands centered on 150, 250 and 410 GHz. The telescope is designed to measure or place an upper limit on inflationary B-mode signals and to probe B-modes originating from gravitationnal lensing of the CMB. The higher EBEX frequencies are designed to enable the measurement and removal of polarized Galactic dust foregrounds which currently limit the measurement of inflationary B-modes. Polarimetry is achieved by rotating an achromatic half-wave plate (HWP) on a superconducting magnetic bearing. In January 2013, EBEX completed 11 days of observations in a flight over Antarctica covering 6,000 square degrees of the southern sky. This marks the first time that kilo-pixel TES bolometer arrays have made science observations on a balloon-borne platform. In this thesis we report on the construction, deployment and data analysis of EBEX. We review the development of the pointing sensors and software used for real-time attitude determination and control, including pre-flight testing and calibration. We then report on the 2013 long duration flight (LD2013) and review all the major stages of the analysis pipeline used to transform the ~1 TB of raw data into polarized sky maps. We review "LEAP", the software framework developed to support the analysis pipeline. We discuss in detail the novel program developed to reconstruct the attitude post-flight and estimate the effect of attitude errors on measured B-mode signals. We describe the bolometer time-stream cleaning procedure including removing the HWP-synchronous signal, and we detail the map making procedure. Finally we present a novel method to measure and subtract instrumental polarization, after which we show Galaxy and CMB maps.

Kinetic inductance detectors (KIDs) are superconducting thin-film microresonators that are sensitive photon detectors. These detectors are a candidate for the next generation of experiments designed to measure the polarization of the cosmic microwave background (CMB). I discuss the basic theory needed to understand the response of a KID to light, focusing on the dynamics of the quasiparticle system. I derive an equation that describes the dynamics of the quasiparticle number, solve it in a simplified form not previously published, and show that it can describe the dynamic response of a detector. Magnetic flux vortices in a superconducting thin film can be a significant source of dissipation, and I demonstrate some techniques to prevent their formation. Based on the presented theory, I derive a corrected version of a widely-used equation for the quasiparticle recombination noise in a KID. I show that a KID consisting of a lumped-element resonator can be sensitive enough to be limited by photon noise, which is the fundamental limit for photometry, at a level of optical loading below levels in ground-based CMB experiments. Finally, I describe an ongoing project to develop multichroic KID pixels that are each sensitive to two linear polarization states in two spectral bands, intended for the next generation of CMB experiments. I show that a prototype 23-pixel array can detect millimeter-wave light, and present characterization measurements of the detectors.

This thesis presents the development of kinetic inductance detectors (KIDs) for cosmic microwave background (CMB) polarimetry. Increasingly precise measurements of the CMB have led to much of our understanding of the observable universe; future measurements of the CMB will require the development of new detectors as progressively fainter signals are targeted. In particular, a measurement of the primordial B-mode polarization signal, which would offer strong evidence of inflation, will require at least a 50 times increase in detector count. KIDs are an attractive detector option for next-generation CMB experiments due to their low-noise and high-multiplexing factor. In this thesis, I present KIDs optimized for ground-based CMB observations, which are sensitive to a 150 GHz spectral band where the CMB spectrum peaks. This research demonstrates the first systematic studies of lumped-element KIDs (LEKIDs) optimized for CMB surveys and shows the readiness of the detectors for on-sky observations. First, I present the design and performance of horn-coupled LEKIDs, which are sensitive to a single polarization. I show that KIDs can meet the stringent noise and sensitivity requirements necessary for a competitive CMB detector. Second, I present a novel method for reducing crosstalk between LEKIDs, which is important for controlling instrument systematics. Third, I present the design and performance of dual-polarization LEKIDs, which are sensitive to orthogonal polarizations within a single spectral band and double the number of detectors per array, increasing the sensitivity. Finally, I present the initial analysis of millimeter-wave observations of a nearby galaxy cluster, Abell 2443, taken with the LEKID-based NIKA2 instrument on the IRAM 30 m telescope. This is part of ongoing research to make high-resolution measurements of the Sunyaev–Zel'dovich effect, seen as a distortion in the CMB spectrum.

Cosmic microwave background observations have been fundamental in forming the standard model of cosmology. Ongoing and upcoming cosmic microwave background experiments aim to confirm this model and push the boundaries of our knowledge to the very first moments of the Universe. Non-cosmological microwave radiation from the Galaxy and beyond, called foregrounds, obscures and contaminates these measurements. Understanding the sources and effects of foregrounds and removing their imprint in cosmic microwave background observations is a major obstacle to making cosmological inferences. This thesis contains my work studying these foregrounds. First, I will present observations of a well-known but poorly understood foreground called anomalous microwave emission. Second, I will present results forecasting the capability of a next-generation satellite experiment to detect cosmic microwave background spectral distortions in the presence of foregrounds. Third, I will present results studying the effect of foregrounds on the cosmic microwave background self-calibration method, which allows experiments to calibrate the telescope polarization angle using the cosmic microwave background itself. Fourth, I will present my analysis characterizing the performance of and producing maps for the E and B Experiment. Fifth, I will present my research contributions to the readout system that used in the laboratory to operate kinetic inductance detectors, which are being developed for cosmic microwave background observations. Lastly, I will conclude with future prospects in the field of foregrounds and cosmic microwave background cosmology.

No description available.

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.