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Using Planck polarization data, we search for and constrain spatial variations of the polarized dust foreground for cosmic microwave background (CMB) observations, specifically in its spectral index, $\beta_d$. Failure to account for such…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Keisuke Osumi , Janet L. Weiland , Graeme E. Addison , Charles L. Bennett

Extracting cosmological information from microwave sky observations requires accurate estimation of the underlying Cosmic Microwave Background (CMB) by removing foreground contamination, instrumental noise, and the effects of beam…

Instrumentation and Methods for Astrophysics · Physics 2026-05-12 Obasho M , Shambhavi Jaiswal , Santanu Das , Krishna Mohan Parattu

We present a new model of the microwave sky in polarization that can be used to simulate data from CMB polarization experiments. We exploit the most recent results from the Planck satellite to provide an accurate description of the diffuse…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Carlos Hervías-Caimapo , Anna Bonaldi , Michael L. Brown

In this paper we are concerned with the solution of Compressed Sensing (CS) problems where the signals to be recovered are sparse in coherent and redundant dictionaries. We extend a primal-dual Newton Conjugate Gradients (pdNCG) method for…

Optimization and Control · Mathematics 2015-07-03 Ioannis Dassios , Kimon Fountoulakis , Jacek Gondzio

We report an improved technique for diffuse foreground minimization from Cosmic Microwave Background (CMB) maps using a new multi-phase iterative internal-linear-combination (ILC) approach in harmonic space. The new procedure consists of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-18 Vipin Sudevan , Pavan K. Aluri , Sarvesh Kumar Yadav , Rajib Saha , Tarun Souradeep

Upcoming ground-based cosmic microwave background experiments will provide CMB maps with high sensitivity and resolution that can be used for high fidelity lensing reconstruction. However, the sky coverage will be incomplete and the noise…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Mark Mirmelstein , Julien Carron , Antony Lewis

Current and future Cosmic Microwave Background (CMB) experiments aim to achieve high-precision reconstruction of the CMB polarization signal, with the most ambitious objective being the detection of primordial $B$ modes sourced by cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Alessandro Carones

The Cosmological Microwave Background (CMB) is of premier importance for the cosmologists to study the birth of our universe. Unfortunately, most CMB experiments such as COBE, WMAP or Planck do not provide a direct measure of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. Bobin , J. -L. Starck , F. Sureau , S. Basak

We present and analyze a preconditioned conjugate gradient method (PCG) for solving spatial network problems. Primarily, we consider diffusion and structural mechanics simulations for fiber based materials, but the methodology can be…

Numerical Analysis · Mathematics 2022-07-18 Morgan Görtz , Fredrik Hellman , Axel Målqvist

Classical iterative methods for tomographic reconstruction include the class of Algebraic Reconstruction Techniques (ART). Convergence of these stationary linear iterative methods is however notably slow. In this paper we propose the use of…

Numerical Analysis · Mathematics 2015-01-22 Siegfried Cools , Pieter Ghysels , Wim van Aarle , J. Sijbers , Wim Vanroose

The Wavelength-Oriented Microwave Background Analysis Team (WOMBAT) is constructing microwave maps which will be more realistic than previous simulations. Our foreground models represent a considerable improvement: where spatial templates…

The efficient solution of moderately large-scale linear systems arising from the KKT conditions in optimal control problems (OCPs) is a critical challenge in robotics. With the stagnation of Moore's law, there is growing interest in…

Optimization and Control · Mathematics 2025-05-21 Shaohui Yang , Toshiyuki Ohtsuka , Brian Plancher , Colin N. Jones

For analyzing maps of the cosmic microwave background sky, it is necessary to mask out the region around the galactic equator where the parasitic foreground emission is strongest as well as the brightest compact sources. Since many of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Martin Bucher , Thibaut Louis

We investigate the science goals achievable with the upcoming generation of ground-based Cosmic Microwave Background polarization experiments and calculate the optimal sky coverage for such an experiment including the effects of…

Polarimetry of the Cosmic Microwave Background (CMB) represents one of the possible diagnostics aimed at testing large-scale magnetism at the epoch of the photon decoupling. The propagation of electromagnetic disturbances in a magnetized…

Astrophysics · Physics 2010-04-29 Massimo Giovannini , Kerstin E. Kunze

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

We present an analysis of errors on the tensor-to-scalar ratio due to residual diffuse foregrounds. We use simulated observations of a CMB polarization satellite, the Cosmic Origins Explorer, using the specifications of the version proposed…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Carlos Hervías-Caimapo , Anna Bonaldi , Michael L. Brown

The polarization of the Cosmic Microwave Background (CMB) radiation carries essential information on early stages of the Universe such as the cosmic inflation, forming cosmological structures through gravitational lensing, and the epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-22 E. Carretti , C. Baccigalupi

The Cosmic Microwave Background (CMB) is a fundamental observational tool in modern cosmology. The linear polarization of the CMB provides a crucial observational tool for exploring new physics, including the inflationary paradigm and…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-12 Vyoma Muralidhara

In this talk I propose the first fast methods which can analyze CMB data taking into account correlated noise, arbitrary beam shapes, non-uniform distribution of integration time on the sky, and partial sky coverage, without the need for…

Astrophysics · Physics 2007-05-23 Benjamin D. Wandelt
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