English
Related papers

Related papers: A Method to Estimate the Primordial Power Spectrum…

200 papers

Pursuing the original idea proposed in our previous paper (Paper I), we improve the method to determine the shape of the initial curvature perturbation spectrum $P(k)$ from the CMB data. The thickness of the last scattering surface (LSS)…

Astrophysics · Physics 2009-10-09 Makoto Matsumiya , Misao Sasaki , Jun'ichi Yokoyama

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…

Astrophysics · Physics 2009-11-07 Pia Mukherjee , Yun Wang

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 develop a new method to reconstruct the power spectrum of primordial curvature perturbations, $P(k)$, by using both the temperature and polarization spectra of the cosmic microwave background (CMB). We test this method using several mock…

Astrophysics · Physics 2009-10-09 Noriyuki Kogo , Misao Sasaki , Jun'ichi Yokoyama

Reconstructing the shape of the primordial power spectrum in a model independent way from cosmological data is a useful consistency check on what is usually assumed regarding early universe physics. It is also our primary window to unknown…

Astrophysics · Physics 2008-11-26 Pia Mukherjee , Yun Wang

We propose an efficient and model independent method for reconstructing the primordial power spectrum from Cosmic Microwave Background (CMB) and large scale structure observations. The algorithm is based on a Monte Carlo principle and…

Astrophysics · Physics 2009-11-10 Steen Hannestad

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

The index $n$ of a power law power spectrum of primordial density fluctuations, $P(k) \propto k^n$, has been estimated using many different techniques. The most precise compare the COBE DMR large angular scale $\Delta T$ to the amplitude of…

Astrophysics · Physics 2007-05-23 Edward L. Wright

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…

Astrophysics · Physics 2009-10-31 Uros Seljak , Matias Zaldarriaga

Recent observations of the cosmic microwave background (CMB) anisotropies and the distribution of galaxies, galaxy clusters, and the Lyman Alpha forest have constrained the shape of the power spectrum of matter fluctuations on large scales…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Aravind Natarajan , Nick Zhu , Naoki Yoshida

We reconstruct the primordial spectrum of the curvature perturbation, $P(k)$, from the observational data of the Wilkinson Microwave Anisotropy Probe (WMAP) by the cosmic inversion method developed recently. In contrast to conventional…

Astrophysics · Physics 2009-10-09 Noriyuki Kogo , Makoto Matsumiya , Misao Sasaki , Jun'ichi Yokoyama

We present a new method for time-efficient and accurate extraction of the power spectrum from future cosmic microwave background (CMB) maps based on properties of peaks and troughs of the Gaussian CMB sky. We construct a statistic…

Astrophysics · Physics 2009-11-06 A. Kashlinsky , C. Hernández--Monteagudo , F. Atrio--Barandela

In this work we explore the possibility of variations in the primordial scalar power spectrum around the power-law shape, as predicted by single-field slow-roll inflationary scenarios. We search for the trace of these fluctuations in a…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Marzieh Farhang , Muhammad Sadegh Esmaeilian

The statistical properties of a map of the primary fluctuations in the cosmic microwave background (CMB) may be specified to high accuracy by a few thousand power spectra measurements, provided the fluctuations are gaussian, yet the number…

Astrophysics · Physics 2009-11-07 Sujata Gupta , Alan F. Heavens

In recent years the goal of estimating different cosmological parameters precisely has set new challenges in the effort to accurately measure the angular power spectrum of CMB. This has required removal of foreground contamination as well…

Astrophysics · Physics 2008-11-26 Rajib Saha , Simon Prunet , Pankaj Jain , Tarun Souradeep

We develop a method to reconstruct the primordial power spectrum, P(k), using both temperature and polarisation data from the joint analysis of a number of Cosmic Microwave Background (CMB) observations. The method is an extension of the…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 Gavin Nicholson , Carlo R. Contaldi

A phenomenological power spectrum of primordial density perturbations has been constructed by using both COBE data to probe the large wavelength region, and a double power law, locally deduced from galaxy catalogs, which describes the…

Astrophysics · Physics 2008-02-03 S. Torres , R. Fabbri , R. Ruffini

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…

Astrophysics · Physics 2016-08-30 Max Tegmark

Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

Constraints on the main cosmological parameters using CMB or large scale structure data are usually based on power-law assumption of the primordial power spectrum (PPS). However, in the absence of a preferred model for the early universe,…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Dhiraj Kumar Hazra , Arman Shafieloo , Tarun Souradeep
‹ Prev 1 2 3 10 Next ›