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Related papers: Sample Variance Denoising in Cylindrical 21-cm Pow…

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Denoising diffusion models are a powerful type of generative models used to capture complex distributions of real-world signals. However, their applicability is limited to scenarios where training samples are readily available, which is not…

Computer Vision and Pattern Recognition · Computer Science 2023-11-20 Ayush Tewari , Tianwei Yin , George Cazenavette , Semon Rezchikov , Joshua B. Tenenbaum , Frédo Durand , William T. Freeman , Vincent Sitzmann

We propose a deep learning analyzing technique with convolutional neural network (CNN) to predict the evolutionary track of the Epoch of Reionization (EoR) from the 21-cm differential brightness temperature tomography images. We use…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Yungi Kwon , Sungwook E. Hong , Inkyu Park

Measurement of the global 21-cm signal during Cosmic Dawn (CD) and the Epoch of Reionization (EoR) is made difficult by bright foreground emission which is 2-5 orders of magnitude larger than the expected signal. Fitting for a…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-20 Michael Pagano , Peter Sims , Adrian Liu , Dominic Anstey , Will Handley , Eloy De Lera Acedo

A number of experiments are set to measure the 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR). The common denominator of these experiments are the large data sets produced, contaminated by various instrumental…

High-redshift 21-cm observations will provide crucial insights into the physical processes of the Epoch of Reionization. Next-generation interferometers such as the Square Kilometer Array will have enough sensitivity to directly image the…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Simon Gazagnes , Léon V. E. Koopmans , Michael H. F. Wilkinson

The 21cm signal of neutral hydrogen contains a wealth of information about the poorly constrained era of cosmological history, the Epoch of Reionization (EoR). Recently, AI models trained on EoR simulations have gained significant attention…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-08 Jasper Solt , Jonathan C. Pober , Stephen H. Bach

Upper limits from the current generation of interferometers targeting the 21-cm signal from high redshifts have recently begun to rule out physically realistic, though still extreme, models of the Epoch of Reionization (EoR). While…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 Jordan Mirocha , Julian B. Muñoz , Steven R. Furlanetto , Adrian Liu , Andrei Mesinger

The redshifted 21-cm signal from the Cosmic Dawn and Epoch of Reionization carries invaluable information about the cosmology and astrophysics of the early Universe. Analyzing data from a sky-averaged 21-cm signal experiment requires…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-16 Anchal Saxena , P. Daniel Meerburg , Christoph Weniger , Eloy de Lera Acedo , Will Handley

We incorporate a contribution to reionization from X-rays within analytic and semi-numerical simulations of the 21-cm signal arising from neutral hydrogen during the epoch of reionization. We explore the impact that X-ray ionizations have…

Astrophysics · Physics 2015-05-13 Lila Warszawski , Paul M. Geil , Stuart Wyithe

The redshifted 21-cm signal is a unique probe of the early universe, particularly the Epoch of Reionization (EoR). While the 21-cm power spectrum has been the primary statistic for parameter inference, it fails to capture the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Anoop Krishna , Deepthi Moorkanat , Hiten , Rajesh Mondal

Measurements of the post-reionization 21-cm bispectrum $B_{{\rm HI}}(\mathbf{k_1},\mathbf{k_2},\mathbf{k_3})$ using various upcoming intensity mapping experiments hold the potential for determining the cosmological parameters at a high…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Debanjan Sarkar , Suman Majumdar , Somnath Bharadwaj

One of the main challenges in probing the reionization epoch using the redshifted 21 cm line is that the magnitude of the signal is several orders smaller than the astrophysical foregrounds. One of the methods to deal with the problem is to…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-25 Dinesh Raut , Tirthankar Roy Choudhury , Raghunath Ghara

Out-of-distribution detection is crucial to the safe deployment of machine learning systems. Currently, unsupervised out-of-distribution detection is dominated by generative-based approaches that make use of estimates of the likelihood or…

A critical challenge in measuring the power spectrum of 21cm emission from cosmic reionization is compensating for the frequency dependence of an interferometer's sampling pattern, which can cause smooth-spectrum foregrounds to appear…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Aaron R. Parsons , Jonathan C. Pober , James E. Aguirre , Christopher L. Carilli , Daniel C. Jacobs , David F. Moore

Predictions for the ability of 21-cm interferometric experiments to discriminate Epoch of Reionization (EoR) signal models are typically limited by the simplicity of data models, whereby foreground signals and characteristics of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Ainulnabilah Nasirudin , Steven Murray , Cathryn Trott , Bradley Greig , Ronniy Joseph , Chris Power

In a sky-averaged 21-cm signal experiment, the uncertainty on the extracted signal depends mainly on the covariance between the foreground and 21-cm signal models. In this paper, we construct these models using the modes of variation…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-19 Anchal Saxena , P. Daniel Meerburg , Eloy de Lera Acedo , Will Handley , Léon V. E. Koopmans

Measurements of the Epoch of Reionization (EoR) 21-cm signal hold the potential to constrain models of reionization. In this paper we consider a reionization model with three astrophysical parameters namely (1) the minimum halo mass which…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-18 Abinash Kumar Shaw , Somnath Bharadwaj , Rajesh Mondal

Current and upcoming radio interferometric experiments are aiming to make a statistical characterization of the high-redshift 21cm fluctuation signal spanning the hydrogen reionization and X-ray heating epochs of the universe. However,…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-19 Nicholas S. Kern , Adrian Liu , Aaron R. Parsons , Andrei Mesinger , Bradley Greig

A multiscale representation-based denoising method for spherical data contaminated with Poisson noise, the multiscale variance stabilizing transform on the sphere (MS-VSTS), has been previously proposed. This paper first extends this…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Jérémy Schmitt , Jean-Luc Starck , Jean-Marc Casandjian , Jalal Fadili , Isabelle Grenier

The next generation 21 cm surveys open a new window onto the early stages of cosmic structure formation and provide new insights about the Epoch of Reionization (EoR). However, the non-Gaussian nature of the 21 cm signal along with the huge…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-18 Héctor J. Hortúa , Luigi Malago , Riccardo Volpi