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The measurements of the statistical properties of the Cosmic Microwave Background (CMB) fluctuations enable us to probe the physics of the very early Universe especially at the epoch of inflation. A particular interest lays on the detection…

宇宙学与河外天体物理 · 物理学 2011-06-07 S. Pires , S. Plaszczynski , A. Lavabre

We present results from the QMAP balloon experiment, which maps the Cosmic Microwave Background (CMB) and probes its angular power spectrum on degree scales. In two separate flights, data were taken in six channels at two frequency bands…

I develop a method for assessing the ability of an instrument, coupled with an observing strategy, to measure the angular power spectrum of the cosmic microwave background (CMB). It allows for efficient calculation of expected parameter…

天体物理学 · 物理学 2009-10-28 Lloyd Knox

The measurements of the angular power spectrum of the Cosmic Microwave Background (CMB) anisotropy has proved crucial to the emergence of cosmology as a precision science in recent years. In this remarkable data rich period, the limitations…

天体物理学 · 物理学 2007-05-23 Sanjit Mitra , Anand S. Sengupta , Tarun Souradeep

We report the most complete analysis to date of observations of the Cosmic Microwave Background (CMB) obtained during the 1998 flight of BOOMERANG. We use two quite different methods to determine the angular power spectrum of the CMB in 20…

We present measurements of the cosmic microwave background (CMB) power spectrum made by the Atacama Cosmology Telescope at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. Our results clearly show the…

Cross-correlating the lensing signals of galaxies and comic microwave background (CMB) fluctuations is expected to provide valuable cosmological information. In particular it may help tighten constraints on parameters describing the…

宇宙学与河外天体物理 · 物理学 2017-09-14 Philipp M. Merkel , Bjoern Malte Schaefer

WMAP observations have accurately determined the position of the first two peaks and dips in the CMB temperature power spectrum. These encode information on the ratio of the distance to the last scattering surface to the sound horizon at…

天体物理学 · 物理学 2008-11-26 Pier Stefano Corasaniti , Alessandro Melchiorri

In this thesis we investigate several aspects related to the theory of fluctuations in the Cosmic Microwave Background. We develop a new algorithm to calculate the angular power spectrum of the anisotropies which is two orders of magnitude…

天体物理学 · 物理学 2007-05-23 Matias Zaldarriaga

We investigate the extent to which foreground cleaned CMB maps can be used to estimate the cosmological parameters at small scales. We use the SMICA method, a blind separation technique which works directly at the spectral level. In this…

宇宙学与河外天体物理 · 物理学 2019-04-17 C. Umiltà , J. F. Cardoso , K. Benabed , M. Le Jeune

The presence of astrophysical emissions in microwave observations forces us to perform component separation to extract the Cosmic Microwave Background (CMB) signal. However, even in the most optimistic cases, there are still strongly…

宇宙学与河外天体物理 · 物理学 2024-09-26 C. Gimeno-Amo , E. Martínez-González , R. B. Barreiro

In experimental microwave maps, point-sources can strongly affect the estimation of the power-spectrum and/or the test of Gaussianity of the Cosmic Microwave Background (CMB) component. As a consequence, their removal from the sky maps…

宇宙学与河外天体物理 · 物理学 2015-05-19 Elsa Patricia R. G. Ramos , Roberto Vio , Paola Andreani

We present Xspect, a method to obtain estimates of the angular power spectrum of the Cosmic Microwave Background (CMB) temperature anisotropies including analytical error bars developed for the Archeops experiment. Cross-power spectra are…

天体物理学 · 物理学 2009-11-10 M. Tristram , J. F. Macias-Perez , C. Renault , D. Santos

In this paper, we focus our attention on the following question: How well can we recover the power spectrum of the cosmic microwave background from the maps of a given experiment?. Each experiment is described by a a pixelization scale, a…

天体物理学 · 物理学 2016-08-15 D. Sáez , J. V. Arnau

Gaussianity and statistical isotropy of the Universe are modern cosmology's minimal set of hypotheses. In this work we introduce a new statistical test to detect observational deviations from this minimal set. By defining the temperature…

宇宙学与河外天体物理 · 物理学 2009-09-30 Thiago S. Pereira , L. Raul Abramo

We show how observations of temperature fluctuations in cosmic microwave background (CMB) can be used to extract information related to the large scale structure, including dark matter distribution, pressure and halo velocities involving…

天体物理学 · 物理学 2007-05-23 Asantha Cooray

Observations of the Cosmic Microwave Background (CMB) radiation have made significant contributions to our understanding of cosmology. While temperature observations of the CMB have greatly advanced our knowledge, the next frontier lies in…

宇宙学与河外天体物理 · 物理学 2024-11-05 Sarvesh Kumar Yadav

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

宇宙学与河外天体物理 · 物理学 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

Most of the cosmological information extracted from the CMB has been obtained through the power spectrum, however there is much more to be learnt from the statistical distribution of the temperature random field. We review some recent…

天体物理学 · 物理学 2015-06-24 Enrique Martinez-Gonzalez

We use weighted mean and median statistics techniques to combine individual cosmic microwave background (CMB) anisotropy detections and determine binned, multipole-space, CMB anisotropy power spectra. The resultant power spectra are peaked.…

天体物理学 · 物理学 2011-07-19 Silviu Podariu , Tarun Souradeep , J. Richard Gott , Bharat Ratra , Michael S. Vogeley