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相关论文: WMAP constraints on Cardassian model

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Cosmic Microwave Background (CMB) anisotropy encodes a lot of information about our Universe. In this paper we take the ground-based CMB observations (GCMB), including the South Pole Telescope (SPT), SPTpol and the Atacama Cosmology…

宇宙学与河外天体物理 · 物理学 2020-07-01 Ke Wang , Qing-Guo Huang

We present a new method based on the N-point probability distribution (pdf) to study non-Gaussianity in cosmic microwave background (CMB) maps. Likelihood and Bayesian estimation are applied to a local non-linear perturbed model up to third…

天体物理学 · 物理学 2015-05-13 P. Vielva , J. L. Sanz

Large-scale modes in the temperature anisotropy power spectrum C_l measured by the Wilkinson Microwave Anisotropy Probe (WMAP), seem to have lower amplitudes (C_2, C_3 and C_4) than that expected in the so called concordance LCDM model. In…

天体物理学 · 物理学 2009-11-07 E. Gaztanaga , J. Wagg , T. Multamaki , A. Montana , D. H. Hughes

The ``Cardassian Expansion Scenario'' was recently proposed by Freese and Lewis (2002) as an alternative to a cosmological constant in explaining the current accelerating universe. In this paper we investigate observational constraints on…

天体物理学 · 物理学 2009-11-07 Zong-Hong Zhu , Masa-Katsu Fujimoto

I present a series of diagrams which illustrate why the cosmic microwave background (CMB) data favor certain values for the cosmological parameters. Various methods to extract these parameters from CMB and non-CMB observations are forming…

天体物理学 · 物理学 2007-05-23 Charles H. Lineweaver

Recently, two issues concerning the three-year WMAP likelihood code were pointed out. On large angular scales ($l \lesssim 30$), a sub-optimal likelihood approximation resulted in a small power excess. On small angular scales ($l \gtrsim…

天体物理学 · 物理学 2007-05-23 Jostein R. Kristiansen , Hans Kristian Eriksen , Oystein Elgaroy

The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information and high…

MAXIMA is a balloon-borne platform for measuring the anisotropy of the Cosmic Microwave Background (CMB). It has measured the CMB power spectrum with a ten-arcminute FWHM beam, corresponding to a detection of the power spectrum out to…

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

Most parameter constraints obtained from cosmic microwave background (CMB) anisotropy data are based on power estimates and rely on approximate likelihood functions; computational difficulties generally preclude an exact analysis based on…

天体物理学 · 物理学 2009-11-06 M. Douspis , J. G. Bartlett , A. Blanchard , M. Le Dour

The cosmic microwave background radiation is supposed to be Gaussian and this hypothesis is in good agreement with the recent very accurate measurements. Nonetheless a tiny amount of non-Gaussianity is predicted by the standard inflation…

宇宙学与河外天体物理 · 物理学 2009-10-06 Davide Pietrobon

We measure the skewness power spectrum of the Cosmic Microwave Background (CMB) anisotropies optimized for a detection of the secondary bispectrum generated by the correlation of the CMB lensing potential with integrated Sachs-Wolfe effect…

宇宙学与河外天体物理 · 物理学 2013-05-29 Erminia Calabrese , Joseph Smidt , Alexandre Amblard , Asantha Cooray , Alessandro Melchiorri , Paolo Serra , Alan Heavens , Dipak Munshi

Recent data from the WMAP, ACT and SPT experiments provide precise measurements of the cosmic microwave background temperature power spectrum over a wide range of angular scales. The combination of these observations is well fit by the…

We investigate the accuracy attainable by forthcoming space-based observations of the cosmic microwave background (CMB) temperature and polarization anisotropy in constraining the dark energy density parameter $\Oq$ and equation of state…

天体物理学 · 物理学 2009-11-07 A. Balbi , C. Baccigalupi , F. Perrotta , S. Matarrese , N. Vittorio

[Abridged] In this paper we explore a local non-linear perturbative model up to third order as a general characterization of the CMB anisotropies. We focus our analysis in large scale anisotropies. At these angular scales, the non-Gaussian…

宇宙学与河外天体物理 · 物理学 2015-05-14 P. Vielva , J. L. Sanz

Previous claims of significant evidence for mirror-parity in the large-scale cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment have been recently echoed in the first study of isotropy and…

宇宙学与河外天体物理 · 物理学 2014-10-20 Assaf Ben-David , Ely D. Kovetz

(Abridged) We present the analysis of the first 18 months of data obtained with the COSMOSOMAS experiment at the Teide Observatory (Tenerife). Three maps have been obtained at 12.7, 14.7 and 16.3 GHz covering 9000 square degrees each with a…

The first three years of observation of the Wilkinson Microwave Anisotropy Probe (WMAP) have provided the most precise data on the anisotropies of the cosmic microwave background (CMB) to date. We investigate the impact of these results and…

天体物理学 · 物理学 2008-11-26 Michael Doran , Georg Robbers , Christof Wetterich

We obtain the reduced CMB data $\{l_A, R, z_*\}$ from WMAP9, WMAP9+BICEP2, Planck+WP and Planck+WP+BICEP2 for the $\Lambda$CDM and $w$CDM models with or without spatial curvature. We then use these reduced CMB data in combination with…

宇宙学与河外天体物理 · 物理学 2015-07-06 Rong-Gen Cai , Zong-Kuan Guo , Bo Tang

I describe briefly the Cosmic Microwave Background (hereafter CMB) physics which explains why high accuracy observations of its spatial structure are a unique observational tool both for the determination of the global cosmological…

天体物理学 · 物理学 2007-05-23 Francois R. Bouchet