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We describe a new map-making code for cosmic microwave background (CMB) observations. It implements fast algorithms for convolution and transpose convolution of two functions on the sphere (Wandelt & G\'{o}rski 2001). Our code can account…

Astrophysics · Physics 2009-11-10 Charmaine Armitage , Benjamin D. Wandelt

Detecting the imprint of inflationary gravitational waves on the $B$-mode polarization of the Cosmic Microwave Background (CMB) is one of the main science cases for current and next-generation CMB experiments. In this work we explore some…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-15 David Alonso , Joanna Dunkley , Sigurd Naess , Ben Thorne

Detection of magnetic-type ($B$-type) polarization in the Cosmic Microwave Background (CMB) radiation plays a crucial role in probing the relic gravitational wave (RGW) background. In this paper, we propose a new method to deconstruct a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Wen Zhao , Deepak Baskaran

We present a new approach to component separation in multifrequency CMB experiments by formulating the problem as that of partitioning the sky into pixel clusters such that within each pixel cluster the foregrounds have similar spectrum,…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-18 Rishi Khatri

We present a framework for cosmological model selection using Neural Networks (NNs) trained directly on simulated Cosmic Microwave Background (CMB) temperature and polarisation maps. By operating at the map level rather than on compressed…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Indira Ocampo , Guadalupe Cañas-Herrera

B-modes of Cosmic Microwave Background (CMB) polarization can be created by a primordial gravitational wave background. If this background was created by Inflation, then the amplitude of the polarization signal is proportional the energy…

Astrophysics · Physics 2008-11-26 Alexandre Amblard , Asantha Cooray , Manoj Kaplinghat

Polarized Galactic foregrounds are one of the primary sources of systematic error in measurements of the B-mode polarization of the Cosmic Microwave Background (CMB). Experiments are becoming increasingly sensitive to complexities in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-13 Brandon S. Hensley , Philip Bull

In this paper, we study statistical classification accuracy of two different Markov field environments for pixelwise image segmentation, considering the labels of the image as hidden states and solving the estimation of such labels as a…

Machine Learning · Computer Science 2013-07-12 Ana Georgina Flesia , Josef Baumgartner , Javier Gimenez , Jorge Martinez

We present a case study describing efforts to optimise and modernise "Modal", the simulation and analysis pipeline used by the Planck satellite experiment for constraining general non-Gaussian models of the early universe via the bispectrum…

Distributed, Parallel, and Cluster Computing · Computer Science 2016-01-27 J. P. Briggs , S. J. Pennycook , J. R. Fergusson , J. Jäykkä , E. P. S. Shellard

In addition to its spectrum and temperature anisotropy, the 2.7K Cosmic Microwave Background is also expected to exhibit a low level of polarization. The spatial power spectrum of the polarization can provide details about the formation of…

Astrophysics · Physics 2009-10-30 Brian Keating , Peter Timbie , Alexander Polnarev , Julia Steinberger

A new iteration bound for the preconditioned conjugate gradient (PCG) method is presented that more accurately captures convergence for systems with clustered eigenspectra, where the classical condition number-based bound is too…

Numerical Analysis · Mathematics 2025-11-18 Philip Soliman , Filipe Cumaru , Alexander Heinlein

Statistical preconditioning enables fast methods for distributed large-scale empirical risk minimization problems. In this approach, multiple worker nodes compute gradients in parallel, which are then used by the central node to update the…

We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual…

Next-generation cosmic microwave background (CMB) surveys are expected to provide valuable information about the primordial universe by creating maps of the mass along the line of sight. Traditional tools for creating these lensing…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-17 Peikai Li , Ipek Ilayda Onur , Scott Dodelson , Shreyas Chaudhari

The polarization modes of the cosmological microwave background are an invaluable source of information for cosmology, and a unique window to probe the energy scale of inflation. Extracting such information from microwave surveys requires…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-04 Jerome Bobin , Florent Sureau , Jean-Luc Starck

The B-mode detection of Cosmic Microwave Background polarization will require new technological developments, able to get sensitivities at least 2 orders of magnitude better than for the E-mode. This really ambitious goal cannot be reached…

Astrophysics · Physics 2007-05-23 S. Cortiglioni , E. Carretti

We present a Gibbs sampling solution to the map-making problem for CMB measurements, building on existing destriping methodology. Gibbs sampling breaks the computationally heavy destriping problem into two separate steps; noise filtering…

We introduce N+2 mapmaking as a novel approach to constructing maps in both intensity and polarization for multi-detector CMB data. The motivation behind this method is two-fold: Firstly, it provides individual temperature detector maps…

Instrumentation and Methods for Astrophysics · Physics 2025-09-29 M. Galloway , H. K. Eriksen , R. M. Sullivan , D. J. Watts , I. K. Wehus , L. Zapelli

Time-resolved observations of the Cosmic Microwave Background (CMB) offer a powerful probe of time-dependent cosmological signals, such as a stochastic gravitational wave background passing through Earth, which imprints a time-varying…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-18 Yilun Guan

Current ground-based submillimeter instruments (e.g. SCUBA-2, SHARC-2 and LABOCA) have hundreds to thousands of detectors, sampled at tens to hundreds of hertz, generating up to hundreds of gigabytes per night. Since noise is correlated…

Instrumentation and Methods for Astrophysics · Physics 2014-05-05 Gaelen Marsden , Adam Brazier , Tim Jenness , Jack Sayers , Douglas Scott