中文
相关论文

相关论文: Parity Asymmetry in the CMBR Temperature Power Spe…

200 篇论文

In the standard model of cosmology, Cosmic Microwave Background (CMB) sky is expected to show no symmetry preferences. Following our previous studies, we explore the presence of any particular parity preference in the latest full-mission…

宇宙学与河外天体物理 · 物理学 2021-03-16 Srikanta Panda , Pavan K. Aluri , Pramoda Kumar Samal , Pranati K. Rath

We investigate the sources of parity asymmetry in the CMB temperature maps using a pixel domain approach. We demonstrate that this anomaly is mainly associated with the presence of two pairs of high asymmetry regions. The first pair of…

宇宙学与河外天体物理 · 物理学 2021-04-14 James Creswell , Pavel Naselsky

If the principle of statistical isotropy is valid, then the angular power spectrum (APS) of cosmic microwave background (CMB) radiation is uncorrelated between different multipoles. We propose a novel technique to analyse any possible…

宇宙学与河外天体物理 · 物理学 2022-12-29 Md Ishaque Khan , Rajib Saha

We perform an analysis of the CMB temperature data taken by the Planck satellite investigating if there is any significant deviation from cosmological isotropy. We look for differences in the spectrum between two opposite hemispheres and…

宇宙学与河外天体物理 · 物理学 2015-01-14 Miguel Quartin , Alessio Notari

We compare the statistics of parity even and odd multipoles of the cosmic microwave background (CMB) sky from PLANCK full mission temperature measurements. An excess power in odd multipoles compared to even multipoles has previously been…

宇宙学与河外天体物理 · 物理学 2018-09-25 Pavan K. Aluri , John P. Ralston , Amanda Weltman

The Parity symmetry of the Cosmic Microwave Background (CMB) pattern as seen by WMAP 7 is tested jointly in temperature and polarization at large angular scale. A Quadratic Maximum Likelihood (QML) estimator is applied to the WMAP 7 year…

宇宙学与河外天体物理 · 物理学 2011-06-21 A. Gruppuso , F. Finelli , P. Natoli , F. Paci , P. Cabella , A. De Rosa , N. Mandolesi

The temperature fluctuations of the Cosmic Microwave Background (CMB) are supposed to be distributed randomly in both magnitude and phase, following to the simplest model of inflation. In this paper, we look at the odd and even multipoles…

宇宙学与河外天体物理 · 物理学 2015-03-19 M. Hansen , A. M. Frejsel , J. Kim , P. Naselsky , F. Nesti

[Abridged] We have produced a cleaned map of the Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data using an improved foreground subtraction technique. We perform an internal linear combination (ILC) to subtract the Galactic foreground…

天体物理学 · 物理学 2008-11-26 Chan-Gyung Park , Changbom Park , J. Richard Gott

We test the hemispherical power asymmetry of the WMAP 7-year low-resolution temperature and polarization maps. We consider two natural estimators for such an asymmetry and exploit our implementation of an optimal angular power spectrum…

宇宙学与河外天体物理 · 物理学 2015-06-12 F. Paci , A. Gruppuso , F. Finelli , A. De Rosa , N. Mandolesi , P. Natoli

We present a CMB temperature power spectrum measurement at large angular scales from WMAP and Planck maps that were cleaned of foregrounds using a template-based approach described in a companion paper. We recover essentially the full-sky…

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

The lack of power anomaly is an unexpected feature observed at large angular scales in the CMB maps produced by the COBE, WMAP and Planck satellites. This signature, which consists in a missing of power with respect to that predicted by the…

宇宙学与河外天体物理 · 物理学 2024-08-20 M. Billi , R. B. Barreiro , E. Martínez-González

We have investigated the odd-parity preference of the WMAP 7 year power spectrum. Comparison with simulation shows the odd-parity preference of WMAP data (2<= l <=22) is anomalous at 4-in-1000 level. We have investigated its origins, and…

宇宙学与河外天体物理 · 物理学 2014-11-20 Jaiseung Kim , Pavel Naselsky

We have investigated the angular correlation in the recent CMB data. In addition to the known large-angle correlation anomaly, we find the lack of correlation at small angles with high statistical significance. We have investigated various…

宇宙学与河外天体物理 · 物理学 2011-09-14 Jaiseung Kim , Pavel Naselsky

We reexamine the evidence of the hemispherical power asymmetry, detected in the CMB WMAP data using a new method. At first, we analyze the hemispherical variance ratios and compare these with simulated distributions. Secondly, working…

天体物理学 · 物理学 2014-11-18 Bartosz Lew

Parity violation found in the Cosmic Microwave Background (CMB) radiation is a crucial clue for the non-standard cosmological model or the possible contamination of various foreground residuals and/or calibration of the CMB data sets. In…

宇宙学与河外天体物理 · 物理学 2012-03-22 P. Naselsky , W. Zhao , J. Kim , S. Chen

We analyze first-year data of WMAP to determine the significance of asymmetry in summed power between arbitrarily defined opposite hemispheres, using maps that we create ourselves with software developed independently of the WMAP team. We…

天体物理学 · 物理学 2010-11-11 P. E. Freeman , C. R. Genovese , C. J. Miller , R. C. Nichol , L. Wasserman

We have investigated non-Gaussianity of our early Universe by comparing the parity asymmetry of the WMAP power spectrum with simulations. We find that odd-parity preference of the WMAP data (2<= l <=18) is anomalous at 4-in-1000 level. We…

宇宙学与河外天体物理 · 物理学 2010-05-25 Jaiseung Kim , Pavel Naselsky

We estimate CMB polarization and temperature power spectra using WMAP 5-year foreground contaminated maps. The power spectrum is estimated by using a model independent method, which does not utilize directly the diffuse foreground templates…

宇宙学与河外天体物理 · 物理学 2011-02-11 Pramoda Kumar Samal , Rajib Saha , Jacques Delabrouille , Simon Prunet , Pankaj Jain , Tarun Souradeep

One of the foundations of the Standard Model of Cosmology is statistical isotropy, which can be tested, among other probes, through the study of the Cosmic Microwave Background (CMB). However, a hemispherical power asymmetry on large scales…

宇宙学与河外天体物理 · 物理学 2023-12-15 C. Gimeno-Amo , R. B. Barreiro , E. Martínez-González , A. Marcos-Caballero

Recent analyses of the WMAP data have suggested that the low-order multipoles of the CMB anisotropy distribution show cosmologically interesting and unexpected morphologies and amplitudes. In this paper, we apply a power equalization (PE)…

天体物理学 · 物理学 2009-11-10 P. Bielewicz , K. M. Gorski , A. J. Banday
‹ 上一页 1 2 3 10 下一页 ›