English
Related papers

Related papers: C_l interpolation for cosmological parameter estim…

200 papers

We present a novel method to significantly speed up cosmological parameter sampling. The method relies on constructing an interpolation of the CMB-log-likelihood based on sparse grids, which is used as a shortcut for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mona Frommert , Dirk Pflueger , Thomas Riller , Martin Reinecke , Hans-Joachim Bungartz , Torsten Ensslin

We apply the Pseudo-C_l formalism to obtain an unbiased, approximate method for efficient simultaneous estimation of several cosmological parameters from large, almost full-sky cosmic microwave background data sets.

Astrophysics · Physics 2007-05-23 Benjamin D. Wandelt , Krzysztof M. Gorski , Eric Hivon

The estimation of cosmological parameters from precision observables is an important industry with crucial ramifications for particle physics. This article discusses the statistical methods presently used in cosmological data analysis,…

High Energy Physics - Theory · Physics 2009-12-15 Andrew R Liddle

I derive analytically the spectrum of the CMB fluctuations. The final result for C_l is presented in terms of elementary functions with an explicit dependence on the basic cosmological parameters. This result is in a rather good agreement…

Astrophysics · Physics 2009-11-07 V. Mukhanov

A new method for estimating the angular power spectrum C_l from cosmic microwave background (CMB) maps is presented, which has the following desirable properties: (1) It is unbeatable in the sense that no other method can measure C_l with…

Astrophysics · Physics 2009-10-07 Max Tegmark

Currently, a method has been developed for the cosmological inflation model with a single scalar field to calculate cosmological parameters such as the power spectrum of scalar and tensor perturbations, their spectral indices, and the…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Katerina Bolshakova , Sergey Chervon

We have developed a fast method for predicting the angular power spectrum, C_l, of the cosmic microwave background given cosmological parameters and a primordial power spectrum of perturbations. After pre--computing the radiation…

Astrophysics · Physics 2009-11-07 Manoj Kaplinghat , Lloyd Knox , Constantinos Skordis

The interpretation of cosmological observables requires the use of increasingly sophisticated theoretical models. Since these models are becoming computationally very expensive and display non-trivial uncertainties, the use of standard…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Marcos Pellejero-Ibañez , Raul E. Angulo , Giovanni Aricó , Matteo Zennaro , Sergio Contreras , Jens Stücker

We consider approaches to cosmological parameter estimation in the inflationary cosmology, focussing on the required accuracy of the initial power spectra. Parametrizing the spectra, for example by power-laws, is well suited to testing the…

Astrophysics · Physics 2009-11-07 Samuel M. Leach , Andrew R. Liddle , Jerome Martin , Dominik J. Schwarz

We propose a technique for determination of the spectral parameters of the cosmological signal and pixel noise using observational data on CMB polarization without any additional assumptions. We introduce the notion of so called crossing…

Astrophysics · Physics 2007-05-23 P. Naselsky , D. Novikov , I. Novikov , J. Silk

The internal linear combination (ILC) method is a popular approach for constructing component-separated maps in cosmic microwave background (CMB) analyses. It optimally combines observed maps at different frequencies to produce an unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-05 Kristen M. Surrao , J. Colin Hill

Bayesian statistics and Markov Chain Monte Carlo (MCMC) algorithms have found their place in the field of Cosmology. They have become important mathematical and numerical tools, especially in parameter estimation and model comparison. In…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-02 Luis E. Padilla , Luis O. Tellez , Luis A. Escamilla , J. Alberto Vazquez

The confrontation of the Cosmic Microwave Background (CMB) theoretical angular power spectrum with available data often requires the calculation of large numbers of power spectra. The standard practice is to use a fast code to compute the…

Astrophysics · Physics 2009-10-31 Kris Sigurdson , Douglas Scott

We discuss the problems of applying Maximum Likelihood methods to the CMB and how one can make it both efficient and optimal. The solution is a generalised eigenvalue problem that allows virtually no loss of information about the parameter…

Astrophysics · Physics 2007-05-23 Andy Taylor , Alan Heavens , Bill Ballinger , Max Tegmark

We present a new method of interpolation for the pixel brightness estimation in astronomical images. Our new method is simple and easily implementable. We show the comparison of this method with the widely used linear interpolation and…

Instrumentation and Methods for Astrophysics · Physics 2013-10-03 A. Popowicz , A. R. Kurek , Z. Filus

We discuss a method of calculating the key cosmological parameters on the basis of a selected scale factor by using exact solutions of the background equations. We specify the formulas for calculating the power spectrum, the spectral…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Sergey V. Chervon , Igor V. Fomin

CMB anisotropy data could put powerful constraints on theories of the evolution of our Universe. Using the observations of the large number of CMB experiments, many studies have put constraints on cosmological parameters assuming different…

Astrophysics · Physics 2015-06-24 Marian Douspis

Cosmological probes pose an inverse problem where the measurement result is obtained through observations, and the objective is to infer values of model parameters which characterize the underlying physical system -- our Universe. Modern…

Instrumentation and Methods for Astrophysics · Physics 2019-05-21 Timur Takhtaganov , Zarija Lukic , Juliane Mueller , Dmitriy Morozov

Much attention has been given to the problem of estimating cosmological parameters from the $C_l$ measured by future experiments. Many of the approaches which are being used either invoke poorly controlled approximations or are…

Astrophysics · Physics 2007-05-23 Benjamin D. Wandelt , Eric Hivon , Krzysztof M. Gorski

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 ›