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Related papers: Wavelet Based Statistics for Enhanced 21cm EoR Par…

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The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this…

Previous studies showed that hydro-climate processes are stochastic and complex systems, and it is difficult to discover the hidden patterns in the all non-stationary data and thoroughly understand the hydro-climate relationships. For the…

Applications · Statistics 2018-10-02 Jianhua Xu

An obstacle to the detection of redshifted 21cm emission from the epoch of reionization (EoR) is the presence of foregrounds which exceed the cosmological signal in intensity by orders of magnitude. We argue that in principle it would be…

With the first phase of the Square Kilometre Array (SKA1) entering into its final pre-construction phase, we investigate how best to maximise its scientific return. Specifically, we focus on the statistical measurement of the 21 cm power…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-14 Bradley Greig , Andrei Mesinger , Léon V. E. Koopmans

The detection of power-laws in real data is a demanding task for several reasons. The two, more frequently met, being: (i) real data possess noise which affects significantly the power-law tails and (ii) there is no solid tool for the…

Data Analysis, Statistics and Probability · Physics 2020-05-13 Yiannis F. Contoyiannis , Stelios Potirakis , Fotios K. Diakonos

We explore the imprints of fuzzy dark matter (FDM) on the redshifted 21~cm signal from the Cosmic Dawn and the Epoch of Reionization by employing the wavelet scattering transform (WST). FDM, composed of ultralight scalar particles with…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-02 Hayato Shimabukuro , Shihang Liu , Bohua Li

We explore the impact of reionization topology on 21-cm statistics. Four reionization models are presented which emulate large ionized bubbles around over-dense regions (21CMFAST/ global-inside- out), small ionized bubbles in over-dense…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-15 Catherine A. Watkinson , Jonathan R. Pritchard

Upcoming 21cm surveys with the SKA1-LOW telescope will enable imaging of the neutral hydrogen distribution on cosmological scales in the early Universe. These surveys are expected to generate huge imaging datasets that will encode more…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Tumelo Mangena , Sultan Hassan , Mario G. Santos

The 21-cm absorption feature reported by the EDGES collaboration is several times stronger than that predicted by traditional astrophysical models. If genuine, a deeper absorption may lead to stronger fluctuations on the 21-cm signal on…

21cm emission from residual neutral hydrogen after the epoch of reionization can be used to trace the cosmological power spectrum of density fluctuations. Using a Fisher matrix formulation, we provide a detailed forecast of the constraints…

Astrophysics · Physics 2009-11-13 Eli Visbal , Abraham Loeb , Stuart Wyithe

The Cosmic Dawn was marked by the formation of the first stars, and preceded the Epoch of Reionization (EoR), when the Universe underwent a fundamental transformation caused by the radiation from these first stars and galaxies.…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Oscar Sage David O'Hara , Fred Dulwich , Eloy de Lera Acedo , Jiten Dhandha , Thomas Gessey-Jones , Dominic Anstey , Anastasia Fialkov

Within the next few years, the Square Kilometer Array (SKA) or one of its pathfinders will hopefully provide a detection of the 21-cm signal fluctuations from the Epoch of Reionization (EoR). Then, the main goal will be to accurately…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-25 Aristide Doussot , Evan Eames , Benoit Semelin

We investigate the Wavelet Scattering Transform (WST) as a tool for the study of Primordial non-Gaussianity (PNG) in Large Scale Structure (LSS), and compare its performance with that achievable via a joint analysis with power spectrum and…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-27 Matteo Peron , Gabriel Jung , Michele Liguori , Massimo Pietroni

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

We introduce 21CMMC: a parallelized, Monte Carlo Markov Chain analysis tool, incorporating the epoch of reionization (EoR) seminumerical simulation 21CMFAST. 21CMMC estimates astrophysical parameter constraints from 21 cm EoR experiments,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Bradley Greig , Andrei Mesinger

The 21-cm signal from the epoch of reionization is non-Gaussian. Current radio telescopes are focused on detecting the 21-cm power spectrum, but in the future the Square Kilometre Array is anticipated to provide a first measurement of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Sambit K. Giri , Anson D'Aloisio , Garrelt Mellema , Eiichiro Komatsu , Raghunath Ghara , Suman Majumdar

The wavelet transform has been used for numerous studies in astrophysics, including signal--noise periodicity and decomposition as well as the signature of differential rotation in stellar light curves. In the present work, we apply the…

Solar and Stellar Astrophysics · Physics 2010-09-28 D. B. de Freitas , I. de C. Leão , B. L. Canto Martins , J. R. De Medeiros

The Epoch of Reionization (EoR) is a crucial link to grasp the complete evolutionary history of the universe. Several attempts with a variety of observables have been utilized in the past to understand the thermal and ionization evolution…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-25 Barun Maity

Detecting a signal from the Epoch of Reionisation (EoR) requires an exquisite understanding of galactic and extra-galactic foregrounds, low frequency radio instruments, instrumental calibration, and data analysis pipelines. In this work we…

Instrumentation and Methods for Astrophysics · Physics 2020-02-27 Ronniy C. Joseph , C. M. Trott , R. B. Wayth , A. Nasirudin

The algorithm of modified wavelet analysis is discussed. It is based on the weighted least squares approximation. Contrary to the Gaussian as a weight function, we propose to use a compact weight function. The accuracy estimates using the…

Instrumentation and Methods for Astrophysics · Physics 2020-05-05 Ivan L. Andronov , Violetta P. Kulynska
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