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相关论文: Probing the Running of Primordial Bispectrum and T…

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Observation of the fine structures (anisotropies, polarization, spectral distortions) of the Cosmic Microwave Background (CMB) is hampered by instabilities, 1/f noise and asymmetries of the radiometers used to carry on the measurements.…

We present estimates of parameters which model the primordial density fluctuations using CMB data from the VSA, 1st year WMAP, CBI and ACBAR along with external priors from 2dF and the HST. Taken at face value there is significant evidence…

天体物理学 · 物理学 2007-05-23 Richard A. Battye , the VSA Collaboration

We study the general properties of the CMB temperature four-point function, specifically its harmonic analogue the angular trispectrum, and illustrate its utility in finding optimal quadratic statistics through the weak gravitational…

天体物理学 · 物理学 2009-11-06 Wayne Hu

In this Letter we study the impact on cosmological parameter estimation, from present and future surveys, due to lensing corrections on CMB temperature and polarization anisotropies beyond leading order. In particular, we show how post-Born…

宇宙学与河外天体物理 · 物理学 2017-05-31 Giovanni Marozzi , Giuseppe Fanizza , Enea Di Dio , Ruth Durrer

(abridged) We explore the statistical properties of non-linear cosmic structures in a flat $\Lambda$CDM cosmology in which the index of the primordial power spectrum for scalar perturbations is allowed to depend on the scale. Within the…

宇宙学与河外天体物理 · 物理学 2015-05-18 C. Fedeli , F. Finelli , L. Moscardini

Accurate ($\lesssim 1\% $) predictions for the anisotropy of the Cosmic Background Radiation (CBR) are essential for using future high-resolution ($\lesssim 1^\circ$) CBR maps to test cosmological models. In many inflationary models the…

天体物理学 · 物理学 2010-01-06 Arthur Kosowsky , Michael S. Turner

Inflation may provide a suitable collider to probe physics at very high energies. In this paper we investigate the impact on the CMB bispectrum of higher spin fields which are long-lived on super-Hubble scales, e.g. partially massless…

宇宙学与河外天体物理 · 物理学 2018-08-30 Gabriele Franciolini , Alex Kehagias , Antonio Riotto , Maresuke Shiraishi

Prior to recombination, Silk damping causes the dissipation of energy from acoustic waves into the monopole of the Cosmic Microwave Background (CMB), resulting in spectral distortions. These can be used to probe the primordial scalar power…

宇宙学与河外天体物理 · 物理学 2015-06-18 Sebastien Clesse , Björn Garbrecht , Yi Zhu

Recent progress in high sensitivity Cosmic Microwave Background (CMB) polarization experiments opens up a window on large scale structure (LSS), as CMB polarization fluctuations on small angular scales can arise from a combination of LSS…

宇宙学与河外天体物理 · 物理学 2018-06-20 Chang Feng , Gilbert Holder

Many inflation models predict that primordial density perturbations have a nonzero three-point correlation function, or bispectrum in Fourier space. Of the several possibilities for this bispectrum, the most commmon is the local-model…

宇宙学与河外天体物理 · 物理学 2015-07-01 Razieh Emami , Emanuela Dimastrogiovanni , Jens Chluba , Marc Kamionkowski

The reconstruction of the CMB lensing potential is based on a Taylor expansion of lensing effects which is known to have poor convergence properties. For lensing of temperature fluctuations, an understanding of the higher order terms in…

天体物理仪器与方法 · 物理学 2015-06-12 Ethan Anderes

Training convolutional recurrent neural networks on first-order Ambisonics signals is a well-known approach when estimating the direction of arrival for speech/sound signals. In this work, we investigate whether increasing the order of…

音频与语音处理 · 电气工程与系统科学 2021-05-07 Nils Poschadel , Robert Hupke , Stephan Preihs , Jürgen Peissig

In this work, we analyze a power-law inflationary potential enhanced with a step that can introduce features in the primordial power spectrum. We focus on the computation of the Spectral Distortions (SD) induced by these features obtained…

宇宙学与河外天体物理 · 物理学 2023-11-27 Jorge Mastache , Wilson Barrera , Raúl Henríquez-Ortiz

Deviations from the blackbody spectral energy distribution of the CMB are a precise probe of physical processes active both in the early universe (such as those connected to particle decays and inflation) and at later times (e.g.…

宇宙学与河外天体物理 · 物理学 2022-10-05 Federico Bianchini , Giulio Fabbian

We calculate the bispectrum of the Cosmic Microwave Background (CMB) temperature anisotropies induced by the second-order fluctuations in the Boltzmann equation. In this paper, which is one of a series of papers on the numerical calculation…

宇宙学与河外天体物理 · 物理学 2015-05-13 Daisuke Nitta , Eiichiro Komatsu , Nicola Bartolo , Sabino Matarrese , Antonio Riotto

We expect a detectable correlation between two seemingly unrelated quantities: the four point function of the cosmic microwave background (CMB) and the amplitude of flux decrements in quasar (QSO) spectra. The amplitude of CMB convergence…

宇宙学与河外天体物理 · 物理学 2011-06-20 Alberto Vallinotto , Matteo Viel , Sudeep Das , David N. Spergel

Spectral distortions of the cosmic microwave background (CMB) are sensitive to energy injection by exotic physics in the early universe. The proposed Primordial Inflation Explorer (PIXIE) mission has the raw sensitivity to provide…

宇宙学与河外天体物理 · 物理学 2021-09-22 Ioana A. Zelko , Douglas P. Finkbeiner

We investigate parity-violating signatures of temperature and polarization bispectra of the cosmic microwave background (CMB) in an inflationary model where a rolling pseudoscalar produces large equilateral tensor non-Gaussianity. By a…

宇宙学与河外天体物理 · 物理学 2013-11-22 Maresuke Shiraishi , Angelo Ricciardone , Shohei Saga

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent amplitude of the primordial curvature…

宇宙学与河外天体物理 · 物理学 2010-01-06 Emiliano Sefusatti , Michele Liguori , Amit P. S. Yadav , Mark G. Jackson , Enrico Pajer

A full account of galaxy evolution in the context of LCDM cosmology requires measurements of the average star-formation rate (SFR) and cold gas abundance across cosmic time. Emission from the CO ladder traces cold gas, and [CII] fine…

宇宙学与河外天体物理 · 物理学 2017-04-05 Eric R. Switzer