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In our previous study, we introduced a machine-learning technique, namely CMBFSCNN, for the removal of foreground contamination in cosmic microwave background (CMB) polarization data. This method was successfully employed on actual…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-19 Ye-Peng Yan , Si-Yu Li , Guo-Jian Wang , Zirui Zhang , Jun-Qing Xia

A detection of the predicted anticorrelation between 21cm and either Ly-alpha or H-alpha from the Epoch of Reionization (EOR) would be a powerful probe of the first galaxies. While 3D intensity maps isolate foregrounds in low k_\parallel…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-06 Abraham R. Neben , Brian Stalder , Jacqueline N. Hewitt , John L. Tonry

Interferometric experiments designed to detect the highly redshifted 21-cm signal from neutral hydrogen are producing increasingly stringent constraints on the 21-cm power spectrum, but some k-modes remain systematics-dominated. Mutual…

High-contrast imaging of exoplanets hinges on powerful post-processing methods to denoise the data and separate the signal of a companion from its host star, which is typically orders of magnitude brighter. Existing post-processing…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Timothy D. Gebhard , Markus J. Bonse , Sascha P. Quanz , Bernhard Schölkopf

In the past decade, HCI surveys provided new insights about the frequency and properties of substellar companions at separation larger than 5 au. In this context, our study aims to detect and characterise potential exoplanets and brown…

Earth and Planetary Astrophysics · Physics 2022-10-05 C. -H. Dahlqvist , J. Milli , O. Absil , F. Cantalloube , L. Matra , E. Choquet , C. del Burgo , J. P. Marshall , M. Wyatt , S. Ertel

The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the two components,…

The bispectrum is a 3-point statistic with the potential to provide additional information beyond power spectra analyses of survey datasets. Radio telescopes which broadly survey the 21cm emission from neutral hydrogen (HI) are a promising…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-11 Steven Cunnington , Catherine Watkinson , Alkistis Pourtsidou

Multiple instruments are pursuing constraints on dark energy, observing reionization and opening a window on the dark ages through the detection and characterization of the 21cm hydrogen line across the redshift spectrum, from nearby to…

Instrumentation and Methods for Astrophysics · Physics 2016-10-11 Daniel C. Jacobs , Jacob Burba , Judd Bowman , Abraham R. Neben , Benjamin Stinnett , Lauren Turner

The upcoming Square Kilometre Array Observatory (SKAO) will produce images of neutral hydrogen distribution during the epoch of reionization by observing the corresponding 21-cm signal. However, the 21-cm signal will be subject to…

Instrumentation and Methods for Astrophysics · Physics 2024-02-29 Michele Bianco , Sambit. K. Giri , David Prelogović , Tianyue Chen , Florent G. Mertens , Emma Tolley , Andrei Mesinger , Jean-Paul Kneib

One of the main challenges facing upcoming CMB experiments will be to distinguish the cosmological signal from foreground contamination. We present a comprehensive treatment of this problem and study how foregrounds degrade the accuracy…

Astrophysics · Physics 2009-10-07 Max Tegmark , Daniel J. Eisenstein , Wayne Hu , Angelica de Oliveira-Costa

Measurements of cosmic microwave background spectral distortions have profound implications for our understanding of physical processes taking place over a vast window in cosmological history. Foreground contamination is unavoidable in such…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-03 Maximilian H. Abitbol , Jens Chluba , J. Colin Hill , Bradley R. Johnson

Existing image synthesis methods for natural scenes focus primarily on foreground control, often reducing the background to simplistic textures. Consequently, these approaches tend to overlook the intrinsic correlation between foreground…

Computer Vision and Pattern Recognition · Computer Science 2025-03-11 Mu Zhang , Yunfan Liu , Yue Liu , Yuzhong Zhao , Qixiang Ye

The post-reionization $(z \le 6)$ neutral hydrogen (HI) 21-cm intensity mapping signal holds the potential to probe the large scale structures, study the expansion history and constrain various cosmological parameters. Here we apply the…

The CHIME radio telescope operates in the frequency bandwidth of 400 to 800 MHz. The CHIME/FRB collaboration has a data pipeline that analyzes the data in real time, suppresses radio frequency interferences (RFI) and searches for FRBs.…

Instrumentation and Methods for Astrophysics · Physics 2023-11-21 K. J. Luke

Many of the current round of experiments searching for anisotropies in the MBR are confronting the problem of how to disentangle the cosmic signal from contamination due to galactic and intergalactic foreground sources. Here we show how…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Albert Stebbins

We consider future balloon-borne and ground-based suborbital experiments designed to search for inflationary gravitational waves, and investigate the impact of residual foregrounds that remain in the estimated cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-03 Y. Fantaye , F. Stivoli , J. Grain , S. M. Leach , M. Tristram , C. Baccigalupi , R. Stompor

The reported detection of the global 21-cm signal by the EDGES collaboration is significantly stronger than standard astrophysical predictions. One possible explanation is an early radio excess above the cosmic microwave background. Such a…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-12 Sudipta Sikder , Rennan Barkana , Anastasia Fialkov , Itamar Reis

Radio frequency interference (RFI) is a significant problem for current and future radio telescopes. We describe here a method for post-correlation cancellation of RFI for the special case of an extended source observed with an…

Astrophysics · Physics 2015-06-24 Geoffrey C. Bower

Residual-domain feature is very useful for Deepfake detection because it suppresses irrelevant content features and preserves key manipulation traces. However, inappropriate residual prediction will bring side effects on detection accuracy.…

Computer Vision and Pattern Recognition · Computer Science 2022-05-03 Zhiqing Guo , Gaobo Yang , Jiyou Chen , Xingming Sun

The motion of an observer in the rest frame of the cosmic 21-cm background induces an anisotropy in the observed background, even when the background is isotropic. The induced anisotropy includes a dipole and a quadrupole, in the order…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-19 Selim C. Hotinli , Kyungjin Ahn