中文
相关论文

相关论文: Harmonic in-painting of CMB sky by constrained Gau…

200 篇论文

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

We propose a new internal linear combination (ILC) method in the pixel space, applicable on large angular scales of the sky, to estimate a foreground minimized Cosmic Microwave Background (CMB) temperature anisotropy map by incorporating…

宇宙学与河外天体物理 · 物理学 2018-11-07 Vipin Sudevan , Rajib Saha

Sparse inpainting techniques are gaining in popularity as a tool for cosmological data analysis, in particular for handling data which present masked regions and missing observations. We investigate here the relationship between sparse…

宇宙学与河外天体物理 · 物理学 2014-02-03 Stephen M. Feeney , Domenico Marinucci , Jason D. McEwen , Hiranya V. Peiris , Benjamin D. Wandelt , Valentina Cammarota

We introduce a new mathematical tool (a direction-dependent probe) to analyse the randomness of purported isotropic Gaussian random fields on the sphere. We apply the probe to assess the full-sky cosmic microwave background (CMB)…

宇宙学与河外天体物理 · 物理学 2020-06-29 J. Hamann , Q. T. Le Gia , I. H. Sloan , Y. G. Wang , R. S. Womersley

In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with respect to the…

宇宙学与河外天体物理 · 物理学 2015-05-28 P. Naselsky , M. Hansen , J. Kim

In this paper we present a new method to estimate a foreground cleaned Cosmic Microwave Background (CMB) map at a resolution of $1^\circ$ by minimizing the non-Gaussian properties of the cleaned map which arise dominantly due to diffuse…

宇宙学与河外天体物理 · 物理学 2015-05-28 Rajib Saha

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

For analyzing maps of the cosmic microwave background sky, it is necessary to mask out the region around the galactic equator where the parasitic foreground emission is strongest as well as the brightest compact sources. Since many of the…

宇宙学与河外天体物理 · 物理学 2015-05-30 Martin Bucher , Thibaut Louis

We analyze the alignment of the low multipoles (quadrupole and octupole) of various maps of the WMAP 5yr release: the CMB maps obtained with ILC and MCMC methods, the CMB map in the V band after foreground reduction, and, for comparison,…

宇宙学与河外天体物理 · 物理学 2010-01-15 Alessandro Gruppuso , Carlo Burigana

[Abridged.] It is conceivable that no single statistical estimator can be sensitive to all forms and levels of non-Gaussianity that may be present in observed CMB data. In recent works a statistical procedure based upon the calculation of…

宇宙学与河外天体物理 · 物理学 2015-01-14 A. Bernui , M. J. Reboucas

ABRIDGED: We introduce and analyze a method for testing statistical isotropy and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature maps, and cross-channel difference maps. We divide the sky into regions of varying…

天体物理学 · 物理学 2009-06-23 Bartosz Lew

As Cosmic Microwave Background (CMB) measurements are becoming more ambitious, the issue of foreground contamination is becoming more pressing. This is especially true at the level of sensitivity, angular resolution and for the sky coverage…

天体物理学 · 物理学 2009-10-31 François R. Bouchet , Richard Gispert

Strong foreground contamination in high resolution CMB data requires masking which introduces statistical anisotropies and renders a full maximum likelihood analysis numerically intractable. Standard analysis methods like the pseudo-C_l…

宇宙学与河外天体物理 · 物理学 2014-03-26 H. F. Gruetjen , E. P. S. Shellard

The WMAP satellite has made available high quality maps of the sky in five frequency bands ranging from 22 to 94 GHz, with the main scientific objective of studying the anisotropies of the Cosmic Microwave Background (CMB). These maps,…

天体物理学 · 物理学 2009-11-13 J. Delabrouille , J. -F. Cardoso , M. Le Jeune , M. Betoule , G. Fay , F. Guilloux

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…

Based on realistic simulations, we propose an hybrid method to reconstruct the lensing potential power spectrum, directly on PLANCK-like CMB frequency maps. It implies using a large galactic mask and dealing with a strong inhomogeneous…

宇宙学与河外天体物理 · 物理学 2015-03-20 S. Plaszczynski , A. Lavabre , L. Perotto , J. -L. Starck

The statistical analysis of the soon to come Planck satellite CMB data will help set tighter bounds on major cosmological parameters. On the way, a number of practical difficulties need to be tackled, notably that several other…

天体物理学 · 物理学 2009-11-13 P. Abrial , Y. Moudden , J. -L. Starck , J. Fadili , J. Delabrouille , M. K. Nguyen

Studies of cosmic microwave background (CMB) are often limited by foreground contamination. Foreground cleaning is performed either in harmonic or pixel space after data cuts have excluded sky areas of strong contamination. We present a…

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

We calculate the CMB anisotropy in compact hyperbolic universe models using the regularized method of images described in paper-I, including the 'line-of-sight `integrated Sachs-Wolfe' effect, as well as the last-scattering surface terms.…

天体物理学 · 物理学 2009-10-31 J. Richard Bond , Dmitry Pogosyan , Tarun Souradeep

The issue of non-Gaussianity is not only related to distinguishing the theories of the origin of primordial fluctuations, but also crucial for the determination of cosmological parameters in the framework of inflation paradigm. We present…

天体物理学 · 物理学 2009-11-10 Lung-Yih Chiang , Pavel D. Naselsky
‹ 上一页 1 2 3 10 下一页 ›