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We describe a class of observational strategies for probing the anisotropies in the cosmic microwave background (CMB) where the instrument scans on rings which can be combined into an n-torus, the {\em ring torus}. This class has the…

Astrophysics · Physics 2009-11-06 Benjamin D. Wandelt , Frode K. Hansen

Angular statistics of cosmological observables are hard to compute. The main difficulty is due to the presence of highly-oscillatory Bessel functions which need to be integrated over. In this paper, we provide a simple and fast method to…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-12 Valentin Assassi , Marko Simonović , Matias Zaldarriaga

Large patterns could exist on the microwave sky as a result of various non-standard possibilities for the large-scale Universe -- rotation or shear, non-trivial topology, and single topological defects are specific examples. All-sky (or…

Astrophysics · Physics 2009-10-31 Emory F. Bunn , Douglas Scott

An harmonic-space maximum-entropy method (MEM) is presented for separating the emission from different physical components in all-sky observations by the forthcoming Planck satellite. The analysis is performed at full Planck resolution,…

Astrophysics · Physics 2009-11-06 V. Stolyarov , M. P. Hobson , M. A. J. Ashdown , A. N. Lasenby

We present LM-GAN, an HDR sky model that generates photorealistic environment maps with weathered skies. Our sky model retains the flexibility of traditional parametric models and enables the reproduction of photorealistic all-weather skies…

Multidimensional imaging, capturing image data in more than two dimensions, has been an emerging field with diverse applications. Due to the limitation of two-dimensional detectors in obtaining the high-dimensional image data, computational…

Image and Video Processing · Electrical Eng. & Systems 2020-06-16 Didem Dogan , Figen S. Oktem

Accurate measurements of the cosmic microwave background (CMB) anisotropies with an angular resolution of a few arcminutes can be used to determine fundamental cosmological parameters such as the densities of baryons, cold and hot dark…

Astrophysics · Physics 2016-01-13 J. Richard Bond , George Efstathiou , Max Tegmark

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

At the pinnacle of computational imaging is the co-optimization of camera and algorithm. This, however, is not the only form of computational imaging. In problems such as imaging through adverse weather, the bigger challenge is how to…

Image and Video Processing · Electrical Eng. & Systems 2023-10-30 Stanley H. Chan

Recent CMB observations have resulted in very precise observational data. A robust and reliable CMB reconstruction technique can lead to efficient estimation of the cosmological parameters. We demonstrate the performance of our methodology…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-31 Albin Joseph , Ujjal Purkayastha , Rajib Saha

In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with respect to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 P. Naselsky , M. Hansen , J. Kim

A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through simple quadrature is of order O(L^5), where 2L…

Astrophysics · Physics 2011-02-11 Y. Wiaux , L. Jacques , P. Vielva , P. Vandergheynst

We discuss full-sky convolution of the instrumental beam with the CMB sky signal in CMB single-dish and interferometry experiments, using the method (Challinor et al. 2000) that the measured temperature and polarization anisotropies are…

Astrophysics · Physics 2009-11-10 Kin-Wang Ng

We apply state-of-the art data analysis methods to a number of fictitious CMB mapping experiments, including 1/f noise, distilling the cosmological information from time-ordered data to maps to power spectrum estimates, and find that in all…

Astrophysics · Physics 2008-11-26 Max Tegmark

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

We describe a new numerical algorithm to obtain high-resolution simulated maps of the Cosmic Microwave Background (CMB), for a broad class of non-Gaussian models. The kind of non-Gaussianity we account for is based on the simple idea that…

Astrophysics · Physics 2009-11-07 Michele Liguori , Sabino Matarrese , Lauro Moscardini

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

Modeling the hemispherical night sky brightness of anthropogenic origin is a demanding computational challenge, due to the intensive calculations required to produce all-sky maps with fine angular resolution including high-order scattering…

Instrumentation and Methods for Astrophysics · Physics 2022-03-30 Miroslav Kocifaj , Salvador Bará , Fabio Falchi

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 are presenting an Internal Linear Combination (ILC) CMB map, in which the foreground is reduced through harmonic variance minimization. We have derived our method by converting a general form of pixel-space approach into spherical…

Astrophysics · Physics 2009-09-29 Jaiseung Kim , Pavel Naselsky , Per Rex Christensen