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相关论文: On using the CMB shift parameter in tests of model…

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Fluctuations in the cosmic neutrino background are known to produce a phase shift in the acoustic peaks of the cosmic microwave background. It is through the sensitivity to this effect that the recent CMB data has provided a robust…

宇宙学与河外天体物理 · 物理学 2020-02-05 Daniel Baumann , Daniel Green , Joel Meyers , Benjamin Wallisch

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

Recent estimates of cosmological parameters derived from Cosmic Microwave Background (CMB) anisotropies are based on the assumption that we know the precise amount of energy density in relativistic particles in the universe, $\omega_{rel}$,…

天体物理学 · 物理学 2008-11-26 R. Bowen , S. H. Hansen , A. Melchiorri , J. Silk , R. Trotta

Non-canonical scaling of the form $\rho_{x} \propto \rho_{m} a^{\xi}$, where $\rho_{x}$ and $\rho_{m}$ are the energy densities of dark energy and dark matter, respectively, provides a natural way to address the coincidence problem -why the…

天体物理学 · 物理学 2009-11-10 Diego Pavon , Somasri Sen , Winfried Zimdahl

Persistent evidence for a cosmic hemispherical asymmetry in the temperature field of cosmic microwave background (CMB) as observed by both WMAP as well as PLANCK increases the possibility of its cosmological origin. Presence of this signal…

宇宙学与河外天体物理 · 物理学 2016-06-28 Suvodip Mukherjee , Pavan K. Aluri , Santanu Das , Shabbir Shaikh , Tarun Souradeep

A maximum-likelihood method is presented for estimating the power spectrum of anisotropies in the cosmic microwave background (CMB) from interferometer observations. The method calculates flat band-power estimates in separate bins in…

天体物理学 · 物理学 2009-11-07 M. P. Hobson , Klaus Maisinger

We consider a double-inflationary model with two massive scalar fields interacting only gravitationally in the context of a flat cold dark matter (CDM) Universe. The cosmic microwave background (CMB) temperature anisotropies produced in…

天体物理学 · 物理学 2009-10-30 Julien Lesgourgues , David Polarski

Following the pioneering observations with COBE in the early 1990s, studies of the cosmic microwave background (CMB) have focused on temperature and polarization anisotropies. CMB spectral distortions - tiny departures of the CMB energy…

High precision measurements of the Cosmic Microwave Background (CMB) anisotropies, as can be expected from the Planck satellite, will require high-accuracy theoretical predictions as well. One possible source of theoretical uncertainty is…

宇宙学与河外天体物理 · 物理学 2009-11-13 Jan Hamann , Amedeo Balbi , Julien Lesgourgues , Claudia Quercellini

We examine Cosmic Microwave Background (CMB) temperature power spectra from the BOOMERANG, MAXIMA, and DASI experiments. We non-parametrically estimate the true power spectrum with no model assumptions. This is a significant departure from…

天体物理学 · 物理学 2007-05-23 Christopher J. Miller , Robert C. Nichol , Christopher Genovese , Larry Wasserman

Observations of the cosmic microwave background (CMB), especially of its frequency spectrum and its anisotropies, both in temperature and in polarization, have played a key role in the development of modern cosmology and our understanding…

宇宙学与河外天体物理 · 物理学 2015-01-20 Martin Bucher

We investigate the anisotropies in the cosmic microwave background in a class of models which possess a positive cosmic energy density but negative pressure, with a constant equation of state w = p/rho < -1. We calculate the temperature and…

天体物理学 · 物理学 2009-07-09 A. E. Schulz , Martin White

Accurate measurements of angular power spectrum of Cosmic Microwave Background (CMB) radiation has lead to marked improvement in the estimates of different cosmological parameters. This has required removal of foreground contamination as…

天体物理学 · 物理学 2009-11-13 Rajib Saha , Pankaj Jain , Tarun Souradeep

We propose a method to extract the projected power spectrum of density perturbations from the distortions in the cosmic microwave background (CMB). The distortions are imprinted onto the CMB by the gravitational lensing effect and can be…

天体物理学 · 物理学 2009-10-31 Uros Seljak , Matias Zaldarriaga

We constrain plausible dark energy models, parametrized by multiple candidate equation of state, using the recently published Cosmic Microwave Background (CMB) temperature anisotropy data from Planck together with the WMAP-9 low-$\ell$…

宇宙学与河外天体物理 · 物理学 2015-04-22 Dhiraj Kumar Hazra , Subhabrata Majumdar , Supratik Pal , Sudhakar Panda , Anjan A. Sen

The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…

宇宙学与河外天体物理 · 物理学 2015-05-20 R. Aurich , S. Lustig

We study the physical limitations placed on CMB temperature and polarization measurements of the initial power spectrum by geometric projection, acoustic physics, gravitational lensing and the joint fitting of cosmological parameters.…

天体物理学 · 物理学 2009-11-10 Wayne Hu , Takemi Okamoto

We report measurements of the cosmic microwave background (CMB) power spectrum from the complete 2008 South Pole Telescope (SPT) data set. We analyze twice as much data as the first SPT power spectrum analysis, using an improved…

Various data analyses of the Cosmic Microwave Background (CMB) provide observational hints of statistical isotropy breaking. Some of these features can be studied within the framework of primordial vector fields in inflationary theories…

宇宙学与河外天体物理 · 物理学 2015-05-28 N. Bartolo , E. Dimastrogiovanni , M. Liguori , S. Matarrese , A. Riotto

A peak has been unambiguously detected in the cosmic microwave background (CMB) angular spectrum. Here we characterize its properties with fits to phenomenological models. We find that the TOCO and BOOM/NA data determine the peak location…

天体物理学 · 物理学 2009-10-31 Lloyd Knox , Lyman Page