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QUBIC, the Q & U Bolometric Interferometer for Cosmology, is a telescope that observes the polarisation of the sky in the millimetre-wavelength range. Its goal is to detect the primordial B-modes of polarisation in the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Alexandre Huchet , Tom Laclavère , Leonora Kardum

We implement a simple, main beam correction in the maximum-likelihood, parametric component separation approach, which allows on accounting for different beamwidths of input maps at different frequencies without any preprocessing. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-19 Arianna Rizzieri , Josquin Errard , Radek Stompor

We describe a fast and accurate method to perform the convolution of a sky map with a general asymmetric main beam along any given scanning strategy. The method is based on the decomposition of the beam as a sum of circular functions, here…

Astrophysics · Physics 2009-11-10 M. Tristram , J. -C. Hamilton , J. F. Macias-Perez , C. Renault

Hyperspectral cameras provide numerous advantages in terms of the utility of the data captured. They capture hundreds of data points per sample (pixel) instead of only the few of RGB or multispectral camera systems. Aerial systems sense…

Image and Video Processing · Electrical Eng. & Systems 2026-01-09 Thomas P. Watson , Eddie L. Jacobs

We present a fast algorithm for generating full sky, high resolution ($\sim 5'$) simulations of the CMB anisotropy pattern. We also discuss the inverse problem, that of evaluating from such a map the full set of $a_{\ell m}$'s and the…

Astrophysics · Physics 2014-10-13 Pio Francesco Muciaccia , Paolo Natoli , Nicola Vittorio

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

Weak gravitational lensing is one of the key probes of cosmology. Cosmic shear surveys aimed at measuring the distribution of matter in the universe are currently being carried out (Pan-STARRS) or planned for the coming decade (DES, LSST,…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 Alberto Vallinotto

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

Forthcoming high-resolution observations of the Cosmic Microwave Background (CMB) radiation will generate datasets many orders of magnitude larger than have been obtained to date. The size and complexity of such datasets presents a very…

Astrophysics · Physics 2016-08-25 Julian Borrill

In this paper, we focus our attention on the following question: How well can we recover the power spectrum of the cosmic microwave background from the maps of a given experiment?. Each experiment is described by a a pixelization scale, a…

Astrophysics · Physics 2016-08-15 D. Sáez , J. V. Arnau

In this article we present a formalism to incorporate the partial-sky maps to the Gibbs ILC algorithm to estimate the joint posterior density of the Cosmic Microwave Background (CMB) signal and the theoretical CMB angular power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Vipin Sudevan , Ujjal Purkayastha , Rajib Saha

We have developed a fast, accurate and generally applicable method for inferring the power spectrum and its uncertainties from maps of the cosmic microwave background (CMB) in the presence of inhomogeneous and correlated noise. For maps…

Astrophysics · Physics 2014-10-13 O. Doré , L. Knox , A. Peel

Mechanisms have been proposed that might rotate the linear polarization of the cosmic microwave background (CMB) as it propagates from the surface of last scatter. In the simplest scenario, the rotation will be uniform across the sky, but…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-02 Vera Gluscevic , Marc Kamionkowski , Asantha Cooray

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 investigate the E/B decomposition of CMB polarization on a masked sky. In real space, operators of E and B mode decomposition involve only differentials of CMB polarization. We may, therefore in principle, perform a clean E/B…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-10 Jaiseung Kim

We present a method for measuring CMB polarization power spectra given incomplete sky coverage and test it with simulated examples such as Boomerang 2001 and MAP. By augmenting the quadratic estimator method with an additional step, we find…

Astrophysics · Physics 2009-10-07 Max Tegmark , Angelica de Oliveira-Costa

We present efficient algorithms for CMB lensing simulation and power spectrum es- timation for flat-sky CMB polarization maps. We build a pure B-mode estimator to remedy E to B leakage due to partial sky coverage. We show that our…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-14 Thibaut Louis , Sigurd Næss , Sudeep Das , Joanna Dunkley , Blake Sherwin

Pixelizations of Platonic solids such as the cube and icosahedron have been widely used to represent spherical data, from climate records to Cosmic Microwave Background maps. Platonic solids have well-known global symmetries. Once we…

Machine Learning · Computer Science 2021-06-15 Mehran Shakerinava , Siamak Ravanbakhsh

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

Deep cosmic microwave background polarization experiments allow a very precise internal reconstruction of the gravitational lensing signal in pricinple. For this aim, likelihood-based or Bayesian methods are typically necessary, where very…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-25 Martin Reinecke , Sebastian Belkner , Julien Carron