English
Related papers

Related papers: What can we learn about Reionization astrophysical…

200 papers

Photoionization and its inverse, electron-ion recombination, are key processes that influence many astrophysical plasmas (and gasses), and the diagnostics that we use to analyse the plasmas. In this review we provide a brief overview of the…

Solar and Stellar Astrophysics · Physics 2023-03-21 D. John Hillier

During the epoch of reionization (EoR), the 21-cm signal allows direct observation of the neutral hydrogen (HI) in the intergalactic medium (IGM). In the post-reionization era, this signal instead probes HI in galaxies, which traces the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Sambit K. Giri , Michele Bianco , Timothée Schaeffer , Ilian T. Iliev , Garrelt Mellema , Aurel Schneider

Photovoltaic (PV) power is affected by weather conditions, making the power generated from the PV systems uncertain. Solving this problem would help improve the reliability and cost effectiveness of the grid, and could help reduce reliance…

Machine Learning · Computer Science 2020-10-07 Yahya Al Lawati , Jack Kelly , Dan Stowell

Transmission spectroscopy, which consists of measuring the wavelength-dependent absorption of starlight by a planet's atmosphere during a transit, is a powerful probe of atmospheric composition. However, the expected signal is typically…

Earth and Planetary Astrophysics · Physics 2015-05-30 N. P. Gibson , S. Aigrain , S. Roberts , T. M. Evans , M. Osborne , F. Pont

The redshifted 21-cm signal from the epoch of reionization (EoR) directly probes the ionization and thermal states of the intergalactic medium during that period. In particular, the distribution of the ionized regions around the radiating…

The observed power spectrum of redshifted 21cm fluctuations is known to be sensitive to the astrophysical properties of the galaxies that drove reionization. Thus, detailed measurements of the 21cm power spectrum and its evolution could…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Han-Seek Kim , J. Stuart B. Wyithe , Jaehong Park , C. G. Lacey

The James Webb Space Telescope (JWST) is expected to enable transformational progress in studying galaxy populations in the very early Universe, during the Epoch of Reionization (EoR). A critical parameter for understanding the sources that…

Astrophysics of Galaxies · Physics 2020-03-25 L. Y. Aaron Yung , Rachel S. Somerville , Gergö Popping , Steven L. Finkelstein

The present work is based on a parametric reconstruction of the deceleration parameter $q(z)$ in a model for the spatially flat FRW universe filled with dark energy and non-relativistic matter. In cosmology, the parametric reconstruction…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Abdulla Al Mamon , Sudipta Das

Enlightening our understanding of the first galaxies responsible for driving reionisation requires detecting the 21-cm signal from neutral hydrogen. Interpreting the wealth of information embedded in this signal requires Bayesian inference.…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-22 Bradley Greig , David Prelogović , Yuxiang Qin , Yuan-Sen Ting , Andrei Mesinger

A new parametrization of the reionization history is presented to facilitate robust comparisons between different observations and with theory. The evolution of the ionization fraction with redshift can be effectively captured by specifying…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Hy Trac

Measuring the small primordial nonGaussianity (PNG) predicted by cosmic inflation theories may help diagnose them. The detectability of PNG by its imprint on the 21cm power spectrum from the epoch of reionization is reassessed here in terms…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Yi Mao , Anson D'Aloisio , Jun Zhang , Paul R. Shapiro

The process of heating and reionization of the Universe at high redshift links small scale structures/galaxy formation and large scale inter-galactic medium properties. Even if the first one is difficult to observe, an observation window is…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-05 Nicolas J. F. Gillet , Dominique Aubert , Florent G. Mertens , Pierre Ocvirk

Observations of the early Universe suggest that reionization was complete by $z\sim6$, however, the exact history of this process is still unknown. One method for measuring the evolution of the neutral fraction throughout this epoch is via…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-19 D. Ďurovčíková , H. Katz , S. E. I. Bosman , F. B. Davies , J. Devriendt , A. Slyz

In this paper we reconstruct the growth and evolution of the cosmic structure of the Universe using Markov Chain Monte Carlo algorithms for Gaussian processes [1]. We estimate the difference between the reconstructions that are calculated…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-29 Mauricio Reyes , Celia Escamilla-Rivera

Gamma-Ray Burst (GRB) explosions from the first generation of stars offer an exciting opportunity to probe the epoch of reionization. Clues about how and when the intergalactic medium was ionized can be read off their UV emission spectrum.…

Astrophysics · Physics 2007-05-23 Abraham Loeb

The measurements of the 21-cm brightness temperature fluctuations from the neutral hydrogen at the Epoch of Reionization (EoR) should inaugurate the next generation of cosmological observables. In this respect, many works have concentrated…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-10 Sebastien Clesse , Laura Lopez-Honorez , Christophe Ringeval , Hiroyuki Tashiro , Michel H. G. Tytgat

Current data of high-redshift absorption-line systems imply that hydrogen reionization occurred before redshifts of about 5. Previous works on reionization by the first stars or quasars have shown that such scenarios are described by a…

Astrophysics · Physics 2009-10-31 Aparna Venkatesan

We perform an analysis of the cosmic reionization in the standard cold dark matter (CDM) paradigm and in alternative dark matter scenarios. Building upon the work of Corasaniti et al. (2017), we predict the reionization history for CDM, for…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Isabella P. Carucci , Pier-Stefano Corasaniti

In the coming decade, low-frequency radio arrays will begin to probe the epoch of reionization via the redshifted 21-cm hydrogen line. Successful interpretation of these observations will require effective statistical techniques for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Vera Gluscevic , Rennan Barkana

Gaussian processes (GPs) are a class of Kernel methods that have shown to be very useful in geoscience and remote sensing applications for parameter retrieval, model inversion, and emulation. They are widely used because they are simple,…

Machine Learning · Computer Science 2020-05-21 J. Emmanuel Johnson , Valero Laparra , Gustau Camps-Valls