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相关论文: Small-Angle CMB Temperature Anisotropies Induced b…

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y-type spectral distortions of the cosmic microwave background allow us to detect clusters and groups of galaxies, filaments of hot gas and the non-uniformities in the warm hot intergalactic medium. Several CMB experiments (on small areas…

宇宙学与河外天体物理 · 物理学 2013-03-13 Rashid A. Sunyaev , Rishi Khatri

We investigate the statistical anisotropy and Gaussianity of temperature fluctuations of Cosmic Microwave Background radiation (CMB) data from {\it Wilkinson Microwave Anisotropy Probe} survey, using the multifractal detrended fluctuation…

天体物理学 · 物理学 2011-08-04 M. Sadegh Movahed , F. Ghasemi , Sohrab Rahvar , M. Reza Rahimi Tabar

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the…

宇宙学与河外天体物理 · 物理学 2011-01-27 Juan Garcia-Bellido , Ruth Durrer , Elisa Fenu , Daniel G. Figueroa , Martin Kunz

We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically…

天体物理学 · 物理学 2008-11-26 Xuelei Chen , Marc Kamionkowski

The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce…

天体物理学 · 物理学 2016-08-25 Lloyd Knox

Cosmic Microwave Background (CMB) anisotropies that result from quantum fluctuations during inflation are explored and the impact of their ``cosmic variance'' on the ability to use existing data to probe inflationary models is studied. We…

天体物理学 · 物理学 2016-08-30 Martin White , Lawrence M. Krauss , Joseph Silk

We detect anisotropy in the cosmic microwave background (CMB) at degree angular scales and confirm a previous detection reported by Wollack et al. (1993). The root-mean-squared amplitude of the fluctuations is $44^{+13}_{-7} \mu$K. This may…

天体物理学 · 物理学 2008-11-26 C. B. Netterfield , N. Jarosik , L. Page , D. Wilkinson , E. Wollack

In this paper we present a complete computation of the Cosmic Microwave Background (CMB) anisotropies up to third order from gravitational perturbations accounting for scalar, vector and tensor perturbations. We then specify our results to…

天体物理学 · 物理学 2008-11-26 G. D'Amico , N. Bartolo , S. Matarrese , A. Riotto

Possible signatures of primordial magnetic fields on the Cosmic Microwave Background (CMB) temperature and polarization anisotropies are reviewed. The signals that could be searched for include excess temperature anisotropies particularly…

天体物理学 · 物理学 2009-11-11 Kandaswamy Subramanian

We present a new method for calculating linear cosmic microwave background (CMB) anisotropy spectra based on integration over sources along the photon past light cone. In this approach the temperature anisotropy is written as a time…

天体物理学 · 物理学 2008-11-26 Uros Seljak , Matias Zaldarriaga

The low quadrupole of the cosmic microwave background (CMB), measured by COBE and confirmed by WMAP, has generated much discussion recently. We point out that the well-known correlation between temperature and polarization anisotropies of…

天体物理学 · 物理学 2009-06-15 Olivier Doré , Gilbert P. Holder , Abraham Loeb

Recent Cosmic Microwave Background (CMB) observations indicate that the temperature anisotropies arise from quantum fluctuations in the inflationary scenario. In the simplest inflationary models, the distribution of CMB temperature…

天体物理学 · 物理学 2009-11-10 J. L. Starck , N. Aghanim , O. Forni

A number of experiments for measuring anisotropies of the Cosmic Microwave Background use scanning strategies in which temperature fluctuations are measured along circular scans on the sky. It is possible, from a large number of such…

天体物理学 · 物理学 2009-10-30 J. Delabrouille , K. M. Górski , E. Hivon

The cosmic microwave background (CMB) radiation is characterized by well-established scales, the 2.7 K temperature of the Planckian spectrum and the $10^{-5}$ amplitude of the temperature anisotropy. These features were instrumental in…

We have searched the 1st-year WMAP W-Band CMB anisotropy map for evidence of cosmic strings. We have set a limit of $\delta = 8 \pi G \mu / c^2 < 8.2 \times 10^{-6}$ at 95% CL for statistical search for a significant number of strings in…

天体物理学 · 物理学 2009-11-10 E. Jeong , G. F. Smoot

We use the analytical model recently introduced in Ref. \cite{lp92}, to investigate the statistics of temperature fluctuations on the cosmic microwave background (CMB), induced by topological defects. The cases of cosmic strings and…

高能物理 - 唯象学 · 物理学 2010-11-01 Leandros Perivolaropoulos

Cosmic string loops contain cusps which decay by emitting bursts of particles. A significant fraction of the released energy is in the form of photons. These photons are injected non-thermally and can hence cause spectral distortions of the…

宇宙学与河外天体物理 · 物理学 2016-02-23 Madeleine Anthonisen , Robert Brandenberger , Alex Laguë , Ian A. Morrison , Daixi Xia

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

天体物理学 · 物理学 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

We report the most complete analysis to date of observations of the Cosmic Microwave Background (CMB) obtained during the 1998 flight of BOOMERANG. We use two quite different methods to determine the angular power spectrum of the CMB in 20…

To minimize instrumentally induced systematic errors, cosmic microwave background (CMB) anisotropy experiments measure temperature differences across the sky using paires of horn antennas, temperature map is recovered from temperature…

天体物理学 · 物理学 2009-08-30 Hao Liu , Ti-Pei Li