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Related papers: Multiparameter estimation with the Pseudo-C_l meth…

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Over the last decade, measurements of the CMB anisotropy has spearheaded the remarkable transition of cosmology into a precision science. However, addressing the systematic effects in the increasingly sensitive, high resolution, `full' sky…

Astrophysics · Physics 2009-03-31 Sanjit Mitra , Anand S. Sengupta , Subharthi Ray , Rajib Saha , Tarun Souradeep

The estimation of cosmological parameters from a given data set requires a construction of a likelihood function which, in general, has a complicated functional form. We adopt a Gaussian copula and constructed a copula likelihood function…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-28 Masanori Sato , Kiyotomo Ichiki , Tsutomu T. Takeuchi

Simulated maps of the microwave background (CMB) radiation are generally created using one of two methods: all-sky simulations use the spherical harmonic transform, while maps covering small areas approximate the sky as flat, allowing the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-22 Mariona Giner Mascarell , Emory F. Bunn

We present a new, semi-analytic framework for estimating the level of residuals present in CMB maps derived from multi-frequency Cosmic Microwave Background (CMB) data and forecasting their impact on cosmological parameters. The data are…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-02 Radek Stompor , Josquin Errard , Davide Poletti

We present a collection of new, open-source computational tools for numerically modeling recent large-scale observational data sets using modern cosmology theory. Specifically, these tools will allow both students and researchers to…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-22 Jacob Moldenhauer , Larry Engelhardt , Keenan Stone , Ezekiel Shuler

The estimation of cosmological parameters from cosmic microwave experiments has almost always been performed assuming gaussian data. In this paper the sensitivity of the parameter estimation to different assumptions on the probability…

Astrophysics · Physics 2009-11-07 Luca Amendola

We present a neural net algorithm for parameter estimation in the context of large cosmological data sets. Cosmological data sets present a particular challenge to pattern-recognition algorithms since the input patterns (galaxy redshift…

Astrophysics · Physics 2007-05-23 Nicholas G. Phillips , A. Kogut

Since cosmology is no longer "the data-starved science", the problem of how to best analyze large data sets has recently received considerable attention, and Karhunen-Loeve eigenvalue methods have been applied to both galaxy redshift…

Astrophysics · Physics 2009-10-07 Max Tegmark , Andy Taylor , Alan Heavens

Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

Astrophysics · Physics 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

We present a neural net algorithm for parameter estimation in the context of large cosmological data sets. Cosmological data sets present a particular challenge to pattern-recognition algorithms since the input patterns (galaxy redshift…

Astrophysics · Physics 2007-05-23 Nicholas G. Phillips , A. Kogut

A functional approximation to implement Bayesian source separation analysis is introduced and applied to separation of the Cosmic Microwave Background (CMB) using WMAP data. The approximation allows for tractable full-sky map…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Simon P. Wilson , Jiwon Yoon

We extend the pure pseudo-power-spectrum formalism proposed recently in the context of the Cosmic Microwave Background polarized power spectra estimation by Smith (2006) to incorporate cross-spectra computed for multiple maps of the same…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-09 J. Grain , M. Tristram , R. Stompor

With the release of the data from the Boomerang and MAXIMA-1 balloon flights, estimates of cosmological parameters based on the Cosmic Microwave Background (CMB) have reached unprecedented precision. In this paper I show that it is possible…

Astrophysics · Physics 2009-10-31 William H. Kinney

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

We develop the framework of Linear Simulation-based Inference (LSBI), an application of simulation-based inference where the likelihood is approximated by a Gaussian linear function of its parameters. We obtain analytical expressions for…

Instrumentation and Methods for Astrophysics · Physics 2025-01-08 Nicolas Mediato-Diaz , Will Handley

The direct evaluation of manifestly optimal, cut-sky CMB power spectrum and bispectrum estimators is numerically very costly, due to the presence of inverse-covariance filtering operations. This justifies the investigation of alternative…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-01 H. F. Gruetjen , J. R. Fergusson , M. Liguori , E. P. S. Shellard

Microwave background temperature and polarization observations are a powerful way to constrain cosmological parameters if the likelihood function can be calculated accurately. The temperature and polarization fields are correlated, partial…

Astrophysics · Physics 2012-04-25 Samira Hamimeche , Antony Lewis

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

Accurate estimation of the Cosmic Microwave Background (CMB) angular power spectrum is enticing due to the prospect for precision cosmology it presents. Galactic foreground emissions, however, contaminate the CMB signal and need to be…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-04 Pallav Chanda , Rajib Saha

It is likely that the observed distribution of the microwave background temperature over the sky is only one realization of the underlying random process associated with cosmological perturbations of quantum-mechanical origin. If so, one…

General Relativity and Quantum Cosmology · Physics 2016-08-24 L. P. Grishchuk , Jérôme Martin
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