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Related papers: Isocurvature modes in the CMB bispectrum

200 papers

Generic models for the origin of structure predict a spectrum of initial fluctuations with a mixture of adiabatic and isocurvature perturbations. Using the observed anisotropies of the cosmic microwave backgound, the matter power spectra…

Astrophysics · Physics 2009-11-10 Maria Beltran , Juan Garcia-Bellido , Julien Lesgourgues , Alain Riazuelo

We investigate the constraints imposed by the first-year WMAP CMB data extended to higher multipole by data from ACBAR, BOOMERANG, CBI and the VSA and by the LSS data from the 2dF galaxy redshift survey on the possible amplitude of…

Astrophysics · Physics 2009-11-10 K. Moodley , M. Bucher , J. Dunkley , P. G. Ferreira , C. Skordis

In this paper we combine partial-wave (`modal') methods with a wavelet analysis of the CMB bispectrum. Our implementation exploits the advantages of both approaches to produce robust, reliable and efficient estimators which can constrain…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Donough Regan , Pia Mukherjee , David Seery

We investigate the CMB $\mu$ distortion in models where two uncorrelated sources contribute to primordial perturbations. We parameterise each source by an amplitude, tilt, running and running of the running. We perform a detailed analysis…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Kimmo Kainulainen , Juuso Leskinen , Sami Nurmi , Tomo Takahashi

We study CMB constraints on non-Gaussianity from isocurvature perturbations of general types. Specifically, we study CDM/neutrino isocurvature perturbations which are uncorrelated or totally correlated with adiabatic ones. Using the data…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Chiaki Hikage , Masahiro Kawasaki , Toyokazu Sekiguchi , Tomo Takahashi

We present a set of formalisms for comparing, evolving and constraining primordial non-Gaussian models through the CMB bispectrum. We describe improved methods for efficient computation of the full CMB bispectrum for any general…

Astrophysics · Physics 2009-09-02 J. R. Fergusson , E. P. S. Shellard

Primordial fluctuations in the relative number densities of particles, or isocurvature perturbations, are generally well constrained by cosmic microwave background (CMB) data. A less probed mode is the compensated isocurvature perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-30 Chen He , Daniel Grin , Wayne Hu

The BB-mode angular correlation power spectrum of CMB is obtained by considering the primordial gravitational waves in the squeezed vacuum state for various inflationary models and results are compared with the joint analysis of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 N. Malsawmtluangi , P. K. Suresh

We consider cosmic microwave background (CMB) anisotropy in models with quintessence taking into account of isocurvature fluctuation in the quintessence. It is shown that, if the primordial fluctuation of the quintessence has a correlation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Takeo Moroi , Tomo Takahashi

This is a review of the Cold Dark Matter model of structure formation, and its variants. The approach is largely from first principles, the main aim being to impart a basic understanding of the relevant theory with an eye to the likely…

Astrophysics · Physics 2010-11-30 Andrew R Liddle , David H Lyth

Within the context of supersymmetric hybrid inflation, we study a multiple-stage inflationary scenario that can generate a primordial spectrum of adiabatic density perturbations with a break at $k_b \simeq 0.05 h Mpc^{-1}$. The presence of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mairi Sakellariadou , Nikos Tetradis

Constraining inflationary models with high precision bispectra across broad parameter ranges is a challenging task, requiring intensive computations at all stages, first, predicting the primordial inflation bispectrum from quantum field…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-29 Bowei Zhang , E. P. S. Shellard , James R. Fergusson

The Cosmic Microwave Background (CMB) anisotropies measurements can provide many clues about the Universe. Although the common belief is that they will allow a very precise measurement of the cosmological parameters (that is, the current…

Astrophysics · Physics 2007-05-23 Alain Riazuelo , David Langlois

In this paper, we investigate some consequences of multiple-field inflation for the cosmic microwave background radiation (CMB). We derive expressions for the amplitudes, the spectral indices and the derivatives of the indices of the CMB…

Astrophysics · Physics 2009-11-10 Bartjan van Tent

The usual inflationary scenario predicts a Gaussian random primordial density fluctuation, different Fourier modes of which do not correlate with each other. In this paper we propose a correlation between these different modes. A simple…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-12 B. Yu , T. Lu

The observed baryon asymmetry, as well as potentially an asymmetry in the dark matter sector, can be produced through dissipative particle production during inflation. A distinctive feature of this mechanism is the generation of matter…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-29 Mar Bastero-Gil , Arjun Berera , Rudnei O. Ramos , Joao G. Rosa

Gravitational waves from inflation induce polarization patterns in the cosmic microwave background (CMB). It is known that there are only two types of non-Gaussianities of the gravitaional waves in the most general scalar field theories…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 Hiroaki W. H. Tahara , Jun'ichi Yokoyama

We study the degree to which the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one polarization $B$ mode with two…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 P. Daniel Meerburg , Joel Meyers , Alex van Engelen , Yacine Ali-Haïmoud

The curl-modes of Cosmic Microwave Background (CMB) polarization probe horizon-scale primordial gravitational waves related to inflation. A significant source of confusion is expected from a lensing conversion of polarization related to…

Astrophysics · Physics 2009-11-10 Asantha Cooray

The recently detected polarization of the cosmic microwave background (CMB) holds the potential for revealing the physics of inflation and gravitationally mapping the large-scale structure of the universe, if so called B-mode signals below…

Astrophysics · Physics 2011-05-12 Wayne Hu , Matthew M. Hedman , Matias Zaldarriaga