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Related papers: General CMB and Primordial Trispectrum Estimation

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In the context of maximum-likelihood parametric component separation for next-generation full-sky CMB polarization experiments, we study the impact of fitting different spectral parameters of Galactic foregrounds in distinct subsets of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Arianna Rizzieri , Clément Leloup , Josquin Errard , Davide Poletti

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

We present a formalism for performance forecasting and optimization of future cosmic microwave background (CMB) experiments. We implement it in the context of nearly full sky, multifrequency, B-mode polarization observations, incorporating…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Josquin Errard , Federico Stivoli , Radek Stompor

Deep learning has emerged as a transformative methodology in modern cosmology, providing powerful tools to extract meaningful physical information from complex astronomical datasets. This paper implements a novel Bayesian graph deep…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-28 Juan Alejandro Pinto Castro , Héctor J. Hortúa , Jorge Enrique García-Farieta , Roger Anderson Hurtado

We present a method designed to estimate the noise power spectrum in the time domain for CMB experiments. The noise power spectrum is extracted from the time ordered data avoiding the contamination coming from sky signal and accounting the…

Astrophysics · Physics 2009-11-10 Alexandre Amblard , Jean-Christophe Hamilton

Modelling of the weak lensing of the CMB will be crucial to obtain correct cosmological parameter constraints from forthcoming precision CMB anisotropy observations. The lensing affects the power spectrum as well as inducing…

Astrophysics · Physics 2010-11-17 Antony Lewis

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

Component separation methods mitigate the cross-contamination between different extragalactic and galactic contributions to cosmic microwave background (CMB) data. This is often done by linearly combining CMB maps from different frequency…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Jack Y. L. Kwok , William R. Coulton , Niall MacCrann , Fiona McCarthy , Boris Bolliet , Blake D. Sherwin

It is well known that CMB temperature anisotropies and polarization can be used to probe the metric perturbations in the early universe. Presently, there exist neither any observational detection of tensor modes of primordial metric…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-23 Gaurav Goswami , Jayanti Prasad

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

Cosmic magnetic fields are observed to be coherent on large scales and could have a primordial origin. Non-Gaussian signals in the cosmic microwave background (CMB) are generated by primordial magnetic fields as the magnetic stresses and…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

We discuss methods for estimating EB and TB spectra of the Cosmic Microwave Background anisotropy maps covering limited sky area. Such odd-parity correlations are expected to vanish whenever parity is not broken. As this is indeed the case…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-18 Julien Grain , Matthieu Tristram , Radek Stompor

The dependence of the bispectrum on the size and shape of the triangle contains a wealth of cosmological information. Here we consider a triangle parameterization which allows us to separate the size and shape dependence. We have…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-22 Abinash Kumar Shaw , Somnath Bharadwaj , Debanjan Sarkar , Arindam Mazumdar , Sukhdeep Singh , Suman Majumdar

Future Cosmic Microwave Background (CMB) experiments will deliver extremely accurate measurements of the E-modes pattern of the CMB polarization field. Given the sharpness of the E-modes transfer functions, such surveys make for a powerful…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Matteo Braglia , Xingang Chen , Dhiraj Kumar Hazra , Lucas Pinol

Detailed knowledge of the primordial power spectrum of curvature perturbations is essential both in order to elucidate the physical mechanism (`inflation') which generated it, and for estimating the cosmological parameters from observations…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-17 Paul Hunt , Subir Sarkar

For the local-type primordial perturbation, it is known that there is an inequality between the bispectrum and the trispectrum. By using the diagrammatic method, we develop a general formalism to systematically construct the similar…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Teruaki Suyama , Shuichiro Yokoyama

Cross-correlations between Cosmic Microwave Background (CMB) temperature and $y$-spectral distortions anisotropies have been previously proposed as a way to measure the local bispectrum parameter $f_{\rm NL}^{\rm loc.}$ in a range of scales…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Andrea Ravenni , Michele Liguori , Nicola Bartolo , Maresuke Shiraishi

This paper generalises the hybrid power spectrum estimator developed in Efstathiou (2004a) to the estimation of polarization power spectra of the cosmic microwave background radiation. The hybrid power spectrum estimator is unbiased and we…

Astrophysics · Physics 2009-11-11 G. Efstathiou

A flexible maximum-entropy component separation algorithm is presented that accommodates anisotropic noise, incomplete sky-coverage and uncertainties in the spectral parameters of foregrounds. The capabilities of the method are determined…

We calculate the primordial power spectrum of tensor perturbations, within the emergent universe scenario, incorporating a version of the Continuous Spontaneous Localization (CSL) model as a mechanism capable of: breaking the initial…

General Relativity and Quantum Cosmology · Physics 2022-12-21 Octavio Palermo , Martín M. Ocampo , Gabriel R. Bengochea , Gabriel León