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相关论文: Fast Parameter Estimation from the CMB Power Spect…

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We implement and investigate a method for measuring departures from scale-invariance, both scale-dependent as well as scale-free, in the primordial power spectrum of density perturbations using cosmic microwave background (CMB) C_l data and…

天体物理学 · 物理学 2009-11-11 Samuel Leach

Unprecedentedly precise cosmic microwave background (CMB) data are expected from ongoing and near-future CMB Stage-III and IV surveys, which will yield reconstructed CMB lensing maps with effective resolution approaching several arcminutes.…

宇宙学与河外天体物理 · 物理学 2016-11-09 Jia Liu , J. Colin Hill , Blake D. Sherwin , Andrea Petri , Vanessa Böhm , Zoltán Haiman

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

The Cosmic Microwave Background (CMB) fluctuations at very small angular scales (less than $10'$) induced by matter sources are computed in a simplified way. The result corrects a previous formula appearing in the literature. The small…

天体物理学 · 物理学 2011-05-10 Mark Hindmarsh

A precise determination of the primordial spectrum of matter density fluctuations at super-horizon scales is essential in understanding large scale structure in the universe. Attempts to constrain or obtain the primordial spectrum using…

天体物理学 · 物理学 2008-11-26 Rafael Bautista , Sergio Torres

We develop two methods for estimating the power spectrum, C_l, of the cosmic microwave background (CMB) from data and apply them to the COBE/DMR and Saskatoon datasets. One method involves a direct evaluation of the likelihood function, and…

天体物理学 · 物理学 2009-10-30 J. R. Bond , A. H. Jaffe , L. Knox

The first year of observations by the Planck satellite mission shows that the cosmic microwave background (CMB) fluctuations are consistent with gaussian statistics in the primordial perturbations, a key prediction of the simplest models of…

宇宙学与河外天体物理 · 物理学 2015-10-19 Ana Achucarro , Vicente Atal , Pablo Ortiz , Jesus Torrado

We present measurements of the power spectra of cosmic infrared background (CIB) and cosmic microwave background (CMB) fluctuations in six frequency bands. Maps at the lower three frequency bands, 95, 150, and 220 GHz (3330, 2000, 1360…

The Cosmic Microwave Background Radiation (CMBR) holds information about almost all the fundamental cosmological parameters, and by performing a likelihood analysis of high precision CMBR fluctuation data, these parameters can be inferred.…

天体物理学 · 物理学 2009-10-31 Steen Hannestad

We present a method for accelerating the calculation of CMB power spectra, matter power spectra and likelihood functions for use in cosmological parameter estimation. The algorithm, called CosmoNet, is based on training a multilayer…

天体物理学 · 物理学 2008-11-26 T. Auld , M. Bridges , M. P. Hobson , S. F. Gull

Since the temperature fluctuations in cosmic microwave background (CMB) on large-angular scales probe length scales that were super-horizon sized at photon decoupling and hence insensitive to microphysical processes, the low-multipole CMB…

宇宙学与河外天体物理 · 物理学 2015-12-30 Cheng Cheng , Qing-Guo Huang

A new method for estimating the power spectrum $C_l$ from cosmic microwave background (CMB) maps was recently presented by the author and applied to the 2 year COBE data. It was found that the spectral resolution $\Delta l$ for COBE could…

天体物理学 · 物理学 2016-08-30 Max Tegmark

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 evaluate the contribution of cosmic microwave background (CMB) polarization spectra to cosmological parameter constraints. We produce cosmological parameters using high-quality CMB polarization data from the ground-based QUaD experiment…

Recent measurements of the cosmic microwave background radiation (CMB), particularly when combined with other datasets, have revolutionised our knowledge of the values of the basic cosmological parameters. Here we summarize the state of…

天体物理学 · 物理学 2007-05-23 Ariel G. Sanchez , Carlton M. Baugh

We present a method to measure the small-scale matter power spectrum using high-resolution measurements of the gravitational lensing of the Cosmic Microwave Background (CMB). To determine whether small-scale structure today is suppressed on…

宇宙学与河外天体物理 · 物理学 2019-01-16 Ho Nam Nguyen , Neelima Sehgal , Mathew Madhavacheril

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

Measuring the primordial matter power spectrum is our primary means of probing unknown physics in the very early universe. We allow the primordial power spectrum to be an arbitrary function, and parametrize it in terms of wavelet band…

天体物理学 · 物理学 2009-11-07 Pia Mukherjee , Yun Wang

In this thesis we investigate several aspects related to the theory of fluctuations in the Cosmic Microwave Background. We develop a new algorithm to calculate the angular power spectrum of the anisotropies which is two orders of magnitude…

天体物理学 · 物理学 2007-05-23 Matias Zaldarriaga

When extracting cosmological information from power spectrum measurements, we must consider the impact of super-sample density fluctuations whose wavelengths are larger than the survey scale. These modes contribute to the mean density…

宇宙学与河外天体物理 · 物理学 2014-12-03 Yin Li , Wayne Hu , Masahiro Takada