English
Related papers

Related papers: Probing the primordial power spectrum with the VSA…

200 papers

We discuss the issue of how precisely we can measure the primordial power spectrum by using future observations of 21 cm fluctuations and cosmic microwave background (CMB). For this purpose, we investigate projected constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kazunori Kohri , Yoshihiko Oyama , Toyokazu Sekiguchi , Tomo Takahashi

We constrain the primordial fluctuation spectrum P(k) by using the new data on the Cosmic Microwave Background (CMB) from the Boomerang and MAXIMA experiments. Our study is based on slow-roll inflationary models, and we consider the…

Astrophysics · Physics 2009-10-31 S. Hannestad , S. H. Hansen , F. L. Villante

(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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. Fedeli , F. Finelli , L. Moscardini

We use statistical inference theory to explore the constraints from future galaxy weak lensing (cosmic shear) surveys combined with the current CMB constraints on cosmological parameters, focusing particularly on the running of the spectral…

Astrophysics · Physics 2009-11-10 Mustapha Ishak , Christopher M. Hirata , Patrick McDonald , Uros Seljak

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…

Astrophysics · Physics 2007-05-23 Ariel G. Sanchez , Carlton M. Baugh

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

We study how the shape of the spectrum of primordial gravitational waves can be constrained by future experiments looking at the B-mode of the Cosmic Microwave Background (CMB) polarization. We implement a Principal Component Analysis (PCA)…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-15 Paolo Campeti , Davide Poletti , Carlo Baccigalupi

In this work we explore the power of future large-scale surveys to constrain possible deviations from the standard single-field slow-roll inflationary scenario. Specifically, we parametrize possible fluctuations around the almost…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-14 Muhammad Sadegh Esmaeilian , Marzieh Farhang , Shirin Khodabakhshi

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-19 Ana Achucarro , Vicente Atal , Pablo Ortiz , Jesus Torrado

We constrain the spectral running by combining cosmic microwave background (CMB) data, baryon acoustic oscillation (BAO) data and the constraint from primordial black holes (PBHs). We find that the constraint from PBHs has a significant…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Jun Li , Qing-Guo Huang

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…

Astrophysics · Physics 2009-11-11 Samuel Leach

We investigate the ability of current CMB data to reliably constrain the form of the primordial power spectrum generated during inflation. We attempt to identify more exotic power spectra that yield equally good fits to the data as simple…

Astrophysics · Physics 2009-06-23 Brian A. Powell , William H. Kinney

We study the capability of future measurements of the galaxy clustering power spectrum to probe departures from a power-law spectrum for primordial fluctuations. On considering the information from the galaxy clustering power spectrum up to…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-05 Mario Ballardini , Fabio Finelli , Cosimo Fedeli , Lauro Moscardini

We show a primordial non-linear "f_NL" term may produce unphysically large CMB anisotropy for a red-tilted primordial power spectrum (n<1), because of coupling to primordial fluctuation on the largest scale. We consider a primordial power…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-14 Jaiseung Kim , Pavel Naselsky

The three-year WMAP(WMAP3), combined with other cosmological observations from galaxy clustering and Type Ia Supernova (SNIa), prefers a non-vanishing running of the primordial spectral index independent of the low CMB multipoles. Motivated…

Astrophysics · Physics 2009-11-11 Bo Feng , Jun-Qing Xia , Jun'ichi Yokoyama , Xinmin Zhang , Gong-Bo Zhao

We argue that observations of the reionization history can be used as a probe of primordial density fluctuations, particularly on small scales. Although the primordial curvature perturbations are well constrained from measurements of cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-29 Teppei Minoda , Shintaro Yoshiura , Tomo Takahashi

Detailed study of the scalar and tensor perturbation spectra can provide much information about the primordial fluctuation-generator, be it inflation or something else. The tensor perturbation spectrum may be observable through its…

Astrophysics · Physics 2007-05-23 L. Knox

We develop a complete set of tools for CMB forecasting, simulation and estimation of primordial running bispectra, arising from a variety of curvaton and single-field (DBI) models of Inflation. We validate our pipeline using mock CMB…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Filippo Oppizzi , Michele Liguori , Alessandro Renzi , Frederico Arroja , Nicola Bartolo

We provide predictions on small-scale cosmological density power spectrum from supernova lensing dispersion. Parameterizing the primordial power spectrum with running $\alpha$ and running of running $\beta$ of the spectral index, we exclude…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-11 Ido Ben-Dayan , Ryuichi Takahashi

We propose and develop a formalism to describe and constrain statistically anisotropic primordial perturbations. Starting from a decomposition of the primordial power spectrum in spherical harmonics, we find how the temperature fluctuations…

Astrophysics · Physics 2009-11-13 C. Armendariz-Picon
‹ Prev 1 2 3 10 Next ›