搜索结果: 1-15 共查到“理学 CMB”相关记录45条 . 查询时间(0.065 秒)
Isotropy of the early universe from CMB anisotropies
The cosmic microwave radiation cosmological parameters scattering baryon density
2014/12/20
The acoustic peak in the cosmic microwave background power spectrum is sensitive to causal processes and cosmological parameters in the early universe up to the time of last scattering. We provide lim...
Nonisotropy in the CMB power spectrum in single field inflation
Inflation the space gradient field the initial value the radiation power spectrum
2014/12/19
Contaldi et al. [C. R. Contaldi, M. Peloso, L. Kofman, and A. Linde, J. Cosmol. Astropart. Phys. 07 (2003) 002] have suggested that an initial period of kinetic energy domination in single field...
Statistical anisotropy of CMB as a probe of conformal rolling scenario
Statistical anisotropy CMB probe conformal rolling scenario
2012/2/21
Search for the statistical anisotropy in the CMB data is a powerful tool for constraining models of the early Universe. In this paper we focus on the recently proposed cosmological scenario with confo...
Future constraints on variations of the fine structure constant from combined CMB and weak lensing measurements
Future constraints variations fine structure constant combined CMB weak lensing measurements
2012/2/21
We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euc...
美国中华医学基金会（CHINA MEDICAL BOARD，简称CMB）成立于1914年11月，是从美国洛克菲勒基金会独立出来，专门资助中国及亚洲其他发展中国家发展医学护理教育、医学研究及公共卫生事业的基金会。迄今已有近百年的历史，为中国现代医学教育、医学研究及公共卫生事业的发展提供了巨额资助。
Isocurvature modes and Baryon Acoustic Oscillations II: gains from combining CMB and Large Scale Structure
Baryon Acoustic Oscillations combining CMB Large Scale Structure
2011/9/29
We consider cosmological parameters estimation in the presence of a non-zero isocurvature contribution in the primordial perturbations. A previous analysis showed that even a tiny amount of isocurvatu...
WMAP 7 year constraints on CPT violation from large angle CMB anisotropies
CMBR theory CMBR experiments
2011/10/18
We constrain the rotation angle $\alpha$ of the linear polarization of CMB photons using the large angular scale (up to $\sim 4^\circ$) signal in WMAP 7 year data. At these scales, the CMB polarizatio...
CMB radiation in an inhomogeneous spherical space
CMB radiation in an inhomogeneous spherical space
2011/10/20
We analyse the CMB radiation in spherical 3-spaces with non-trivial topology. The focus is put on an inhomogeneous space which possesses observer dependent CMB properties. The suppression of the CMB a...
Constraints from the CMB temperature and other common observational data-sets on variable dark energy density models
Cosmology Dark energy Thermodynamics
2011/10/13
The thermodynamic and dynamical properties of a variable dark energy model with density scaling as rho_x \propto (1+z)^m, z being the redshift, are discussed following the outline of Jetzer et al. Thi...
Detecting relic gravitational waves in the CMB: A statistical bias
Detecting relic gravitational waves statistical bias
2011/10/13
Analyzing the imprint of relic gravitational waves (RGWs) on the cosmic microwave background (CMB) power spectra provides a way to determine the signal of RGWs. In this Letter, we discuss a statistica...
An Estimator for statistical anisotropy from the CMB bispectrum
Estimator statistical anisotropy CMB bispectrum
2011/10/13
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 ve...
Characterisation of the non-Gaussianity of radio and IR point-sources at CMB frequencies
ology: Cosmic Microwave Background, large scale structures Galaxiesstatistics, Infrared: galaxies Radio continuum: galaxies Methods: statistical
2011/10/8
The present study focuses on the characterisation of the non-Gaussianity produced by radio point-sources and, for the first time, by infrared sources in the frequency range of the CMB from 30 to 350 G...
Violation of the Rotational Invariance in the CMB Bispectrum
Violation Rotational Invariance CMB Bispectrum
2011/9/27
We investigate a statistical anisotropy on the Cosmic Microwave Background (CMB) bispectrum which can be generated from the primordial non-Gaussianity induced by quantum fluctuations of a vector field...
In the context of the geometrical analysis of weakly non Gaussian CMB maps, the 2D differential extrema counts as functions of the excursion set threshold is derived from the full moments expansion of...
Non Gaussian extrema counts for CMB maps
non Gaussian extrema counts CMB maps Cosmology and Extragalactic Astrophysics
2011/9/30
Abstract: In the context of the geometrical analysis of weakly non Gaussian CMB maps, the 2D differential extrema counts as functions of the excursion set threshold is derived from the full moments ex...