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相关论文: The effect of asymmetric beams in the Wilkinson Mi…

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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…

Several accurate analyses have revealed a statistically significant North-South ecliptic asymmetry in the large-angle correlations strength of the Cosmic Microwave Background (CMB) radiation temperature field data from the Wilkinson…

天体物理学 · 物理学 2009-02-23 Armando Bernui

In recent years the goal of estimating different cosmological parameters precisely has set new challenges in the effort to accurately measure the angular power spectrum of CMB. This has required removal of foreground contamination as well…

天体物理学 · 物理学 2008-11-26 Rajib Saha , Simon Prunet , Pankaj Jain , Tarun Souradeep

We present new full-sky temperature maps in five frequency bands from 23 to 94 GHz, based on the first three years of the WMAP sky survey. The new maps, which are consistent with the first-year maps and more sensitive, incorporate…

We present local extrema studies of two models that introduce a preferred direction into the observed cosmic microwave background (CMB) temperature field. In particular, we make a frequentist comparison of the one- and two-point statistics…

宇宙学与河外天体物理 · 物理学 2014-11-20 Zhen Hou , A. J. Banday , K. M. Gorski , N. E. Groeneboom , H. K. Eriksen

Over the last decade, measurements of the CMB anisotropy has spearheaded the remarkable transition of cosmology into a precision science. However, addressing the systematic effects in the increasingly sensitive, high resolution, `full' sky…

天体物理学 · 物理学 2009-03-31 Sanjit Mitra , Anand S. Sengupta , Subharthi Ray , Rajib Saha , Tarun Souradeep

Asymmetric beams can create significant bias in estimates of the power spectra from CMB experiments. With the temperature power spectrum many orders of magnitude stronger than the B-mode power spectrum any systematic error that couples the…

宇宙学与河外天体物理 · 物理学 2017-03-08 Christopher G. R. Wallis , Michael L. Brown , Richard A. Battye , Giampaolo Pisano , Luca Lamagna

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

We present two novel methods for the estimation of the angular power spectrum of cosmic microwave background (CMB) anisotropies. We assume an absolute CMB experiment with arbitrary asymmetric beams and arbitrary sky coverage. The methods…

宇宙学与河外天体物理 · 物理学 2017-01-25 Elina Keihänen , Kimmo Kiiveri , Hannu Kurki-Suonio , Martin Reinecke

We report on the first flight of the balloon-borne QMAP experiment. The experiment is designed to make a map of the cosmic microwave background anisotropy on angular scales from 0.7 to several degrees. Using the map we determine the angular…

The cosmic microwave background (CMB) temperature maps published by the Wilkinson Microwave Anisotropy Probe (WMAP) team are found to be inconsistent with the differential time-ordered data (TOD), from which the maps are reconstructed. The…

宇宙学与河外天体物理 · 物理学 2009-09-22 Hao Liu , Ti-Pei Li

We investigate weak lensing effect on cosmic microwave background (CMB) in the presence of dipole anisotropy. The approach of flat-sky approximation is considered. We determine the functions $\sigma_0^2$ and $\sigma_2^2$ that appear in…

宇宙学与河外天体物理 · 物理学 2019-07-24 Abhineet Agarwal , Naveen K. Singh , Pankaj Jain , Prabhakar Tiwari

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its…

The Wilkinson Microwave Anisotropy Probe (WMAP) has measured lower amplitudes for the temperature quadrupole and octopole anisotropies than expected in the best fitting (concordance) Lambda-dominated cold dark matter cosmology. Some authors…

天体物理学 · 物理学 2009-11-10 G. Efstathiou

We search for hidden mirror symmetries at large angular scales in the WMAP 7 year Internal Linear Combination map of CMB temperature anisotropies using global pixel based estimators introduced for this aim. Two different axes are found for…

宇宙学与河外天体物理 · 物理学 2015-03-19 F. Finelli , A. Gruppuso , F. Paci , A. A. Starobinsky

Under the assumption that the concordance Lambda cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…

天体物理学 · 物理学 2007-05-23 Louise M. Griffiths , Charles H. Lineweaver

The standard models of inflation predict statistically homogeneous and isotropic primordial fluc- tuations, which should be tested by observations. In this paper we test the statistical isotropy of the mean of the CMB temperature…

宇宙学与河外天体物理 · 物理学 2015-03-19 Daichi Kashino , Kiyotomo Ichiki , Tsutomu T. Takeuchi

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck…

宇宙学与河外天体物理 · 物理学 2025-09-05 Laura Herold , Graeme E. Addison , Charles L. Bennett , Hayley C. Nofi , J. L. Weiland

Precise measurements of the Cosmic Microwave Background (CMB) anisotropy have been one of the foremost concerns in modern cosmology as it provides valuable information on the cosmology of the universe. However, an accurate estimation of the…

宇宙学与河外天体物理 · 物理学 2013-09-20 Fidy A. Ramamonjisoa , Subharthi Ray , Sanjit Mitra , Tarun Souradeep

Local scaling properties of the co-added foreground-cleaned three-year Wilkinson Microwave Anisotropy Probe (WMAP) data are estimated using weighted scaling indices. The scaling index method (SIM) is - for the first time - adapted and…

天体物理学 · 物理学 2009-05-21 C. Raeth , P. Schuecker , A. J. Banday