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In order to extract cosmological information from observations of the millimeter and submillimeter sky, foreground components must first be removed to produce an estimate of the cosmic microwave background (CMB). We developed a…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-10 Matthew A. Petroff , Graeme E. Addison , Charles L. Bennett , Janet L. Weiland

The WMAP satellite has made available high quality maps of the sky in five frequency bands ranging from 22 to 94 GHz, with the main scientific objective of studying the anisotropies of the Cosmic Microwave Background (CMB). These maps,…

Astrophysics · Physics 2009-11-13 J. Delabrouille , J. -F. Cardoso , M. Le Jeune , M. Betoule , G. Fay , F. Guilloux

In this paper, we develop a theoretical framework for analyzing the measurable information content of an unknown scene through an active electromagnetic imaging array. We consider monostatic and multistatic array architectures in a…

Information Theory · Computer Science 2018-08-07 Babak Mamandipoor , Amin Arbabian , Upamanyu Madhow

We present an improved Global Sky Model (GSM) of diffuse galactic radio emission from 10 MHz to 5 THz, whose uses include foreground modeling for CMB and 21 cm cosmology. Our model improves on past work both algorithmically and by adding…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 Haoxuan Zheng , Max Tegmark , Joshua S. Dillon , Doyeon A. Kim , Adrian Liu , Abraham Neben , Justin Jonas , Patricia Reich , Wolfgang Reich

In this paper we estimate diffuse foreground minimized Cosmic Microwave Background (CMB) Stokes Q and U polarization maps based upon the fundamental concept of Gaussian nature of CMB and strong non-Gaussian nature of astrophysical polarized…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-10 Ujjal Purkayastha , Rajib Saha

The cross-correlation between 21-cm intensity mapping experiments and photometric surveys of galaxies (or any other cosmological tracer with a broad radial kernel) is severely degraded by the loss of long-wavelength radial modes due to…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-19 Caroline Guandalin , Isabella P. Carucci , David Alonso , Kavilan Moodley

Precise estimation of cosmological parameters from the cosmic microwave background (CMB) remains a central goal of modern cosmology and a key test of inflationary physics. However, this task is fundamentally limited by strong foreground…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Larissa Santos , Camila P. Novaes , Elisa G. M. Ferreira , Carlo Baccigalupi

We present the first tests of a new method, the Correlated Component Analysis (CCA) based on second-order statistics, to estimate the mixing matrix, a key ingredient to separate astrophysical foregrounds superimposed to the Cosmic Microwave…

Astrophysics · Physics 2016-04-26 A. Bonaldi , L. Bedini , E. Salerno , C. Baccigalupi , G. De Zotti

We compare multiple foreground-cleaning pipelines for estimating the tensor-to-scalar ratio, $r$, using simulated maps of the planned CMB-S4 experiment within the context of the South Pole Deep Patch. To evaluate robustness, we analyze bias…

One of the main challenges for future 21 cm observations is to remove foregrounds which are several orders of magnitude more intense than the HI signal. We propose a new technique for removing foregrounds of the redshifted 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jungyeon Cho , A. Lazarian , P. Timbie

As Cosmic Microwave Background (CMB) measurements are becoming more ambitious, the issue of foreground contamination is becoming more pressing. This is especially true at the level of sensitivity, angular resolution and for the sky coverage…

Astrophysics · Physics 2009-10-31 François R. Bouchet , Richard Gispert

We propose a novel method to probe the global 21-cm background. This background experiences the integrated Sachs-Wolfe effect (ISW) as the cosmic microwave background does. The 21-cm ISW is modulated by the spectral shape of the global…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-14 Kyungjin Ahn , Minji Oh

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

We present the Bayesian Global Sky Model (B-GSM), a new absolutely calibrated model of the diffuse Galactic foreground at frequencies below 408 MHz. We assemble a dataset of publicly available diffuse emission maps at frequencies between 45…

Instrumentation and Methods for Astrophysics · Physics 2025-04-08 George Carter , Will Handley , Mark Ashdown , Nima Razavi-Ghods

Line intensity mapping using atomic hydrogen (HI) has the potential to efficiently map large volumes of the universe if the signal can be successfully separated from overwhelmingly bright radio foreground emission. This motivates…

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 present a data-driven technique to analyze multifrequency images from upcoming cosmological surveys mapping large sky area. Using full information from the data at the two-point level, our method can simultaneously constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 Yun-Ting Cheng , Benjamin D. Wandelt , Tzu-Ching Chang , Olivier Dore

A great deal of experimental effort is currently being devoted to the precise measurements of the cosmic microwave background (CMB) sky in temperature and polarisation. Satellites, balloon-borne, and ground-based experiments scrutinize the…

In this work we present a Neural Network (NN) algorithm for the identification of the appropriate parametrization of diffuse polarized Galactic emissions in the context of Cosmic Microwave Background (CMB) $B$-mode multi-frequency…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Farida Farsian , Nicoletta Krachmalnicoff , Carlo Baccigalupi
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