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We perform a Fisher analysis to estimate the expected constraints on the Epoch of Reionization (EoR) model parameters (i.e., minimum virial temperature, the ionizing efficiency and the mean free path of ionizing photons) taking into account…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-04 Hayato Shimabukuro , Shintaro Yoshiura , Keitaro Takahashi , Shuichiro Yokoyama , Kiyotomo Ichiki

The observations of the redshifted 21-cm signal from neutral hydrogen are a promising probe for understanding the Cosmic Dawn and the Epoch of Reionisation (EoR). One of the primary obstacles to the statistical detection of the Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-22 Eeshan Beohar , Abhirup Datta , Anshuman Tripathi , Samit Kumar Pal , Rashmi Sagar

BayesEoR is a GPU-accelerated, MPI-compatible Python package for estimating the power spectrum of redshifted 21-cm emission from interferometric observations of the Epoch of Reionization (EoR). Utilizing a Bayesian framework, BayesEoR…

Instrumentation and Methods for Astrophysics · Physics 2025-01-23 Peter H. Sims , Jacob Burba , Jonathan C. Pober

Observations with radio arrays that target the 21-cm signal originating from the early Universe suffer from a variety of systematic effects. An important class of these are reflections and spurious couplings between antennas. We apply a…

(Abridged) Noise considerations for experiments that aim to statistically estimate the 21 cm signal from high redshift neutral hydrogen during the Epoch of Reionisation (EoR) using interferometric data are typically computed assuming a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Cathryn M. Trott

The GMRT Epoch of Reionization (EoR) experiment is an ongoing effort to measure the power spectrum from neutral hydrogen at high redshift. We have previously reported an upper limit of (70 mK)^2 at wavenumbers of k=0.65 h/Mpc using a basic…

We explore methods for robust estimation of the 21 cm signal from the Epoch of Reionisation (EoR). A Kernel Density Estimator (KDE) is introduced for measuring the spatial temperature fluctuation power spectrum from the EoR. The KDE…

We present the first limits on the Epoch of Reionization (EoR) 21-cm HI power spectra, in the redshift range $z=7.9-10.6$, using the Low-Frequency Array (LOFAR) High-Band Antenna (HBA). In total 13\,h of data were used from observations…

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

We present a broadband map of polarized diffuse emission at 167-198 MHz developed from data from the Murchison Widefield Array (MWA). The map is designed to improve visibility simulation and precision calibration for 21 cm Epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Ruby Byrne , Miguel F. Morales , Bryna Hazelton , Ian Sullivan , Nichole Barry , Christene Lynch , Jack L. B. Line , Daniel C. Jacobs

We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in the Phase I upper…

We use the Fisher matrix formalism and semi-numerical simulations to derive quantitative predictions of the constraints that power spectrum measurements on next-generation interferometers, such as the Hydrogen Epoch of Reionization Array…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-26 Aaron Ewall-Wice , Jacqueline Hewitt , Andrei Mesinger , Joshua S. Dillon , Adrian Liu , Jonathan Pober

Recently, the Hydrogen Epoch of Reionization Array (HERA) collaboration has produced the experiment's first upper limits on the power spectrum of 21-cm fluctuations at z~8 and 10. Here, we use several independent theoretical models to infer…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-21 The HERA Collaboration , Zara Abdurashidova , James E. Aguirre , Paul Alexander , Zaki Ali , Yanga Balfour , Rennan Barkana , Adam Beardsley , Gianni Bernardi , Tashalee Billings , Judd Bowman , Richard Bradley , Phillip Bull , Jacob Burba , Steven Carey , Christopher Carilli , Carina Cheng , David DeBoer , Matthew Dexter , Eloy de Lera Acedo , Joshua Dillon , John Ely , Aaron Ewall-Wice , Nicolas Fagnoni , Anastasia Fialkov , Randall Fritz , Steven Furlanetto , Kingsley Gale-Sides , Brian Glendenning , Deepthi Gorthi , Bradley Greig , Jasper Grobbelaar , Ziyaad Halday , Bryna Hazelton , Stefan Heimersheim , Jacqueline Hewitt , Jack Hickish , Daniel Jacobs , Austin Julius , Nicholas Kern , Joshua Kerrigan , Piyanat Kittiwisit , Saul Kohn , Matthew Kolopanis , Adam Lanman , Paul La Plante , Telalo Lekalake , David Lewis , Adrian Liu , Yin-Zhe Ma , David MacMahon , Lourence Malan , Cresshim Malgas , Matthys Maree , Zachary Martinot , Eunice Matsetela , Andrei Mesinger , Jordan Mirocha , Mathakane Molewa , Miguel Morales , Tshegofalang Mosiane , Julian Munoz , Steven Murray , Abraham Neben , Bojan Nikolic , Chuneeta Devi Nunhokee , Aaron Parsons , Nipanjana Patra , Samantha Pieterse , Jonathan Pober , Yuxiang Qin , N. Razavi-Ghods , Itamar Reis , Jon Ringuette , James Robnett , Kathryn Rosie , Mario Santos , Sudipta Sikder , Peter Sims , Craig Smith , Angelo Syce , Nithyanandan Thyagarajan , Peter Williams , Haoxuan Zheng

The 21~cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation. The main difficulty in measuring the 21 cm signal is the presence of bright foregrounds that require very accurate…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-20 N. Charles , G. Bernardi , H. L. Bester , O. M. Smirnov , C. Carilli , P. M. Keller , N. Kern , B. Nikolic , N. Thyagarajan , E. de Lera Acedo , N. Fagnoni , M. G. Santos

We present a halo-model-based approach to calculate the cross-correlation between $\rm{21\,cm}$ HI intensity fluctuations and $\rm{Ly}\alpha$ emitters (LAE) during the epoch of reionization (EoR). Ionizing radiation around dark matter halos…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-06 Chang Feng , Asantha Cooray , Brian Keating

Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by reducing foreground sensitivity while linking ionization morphology to galaxies. We quantify the constraining power of 21cm-Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yannic Pietschke , Anne Hutter , Caroline Heneka

We test the hypothesis that limitations in the sky model used to calibrate an interferometric radio telescope, where the model contains extended radio sources, will generate bias in the Epoch of Reionisation (EoR) power spectrum. The…

Instrumentation and Methods for Astrophysics · Physics 2017-11-29 Cathryn M. Trott , Randall B. Wayth

The aim of the LOFAR Epoch of Reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21cm signal. This signal is weaker by several orders of magnitude than the astrophysical foreground signals and hence, in…

We explore how chromatic RFI flags affect 21-cm power spectrum measurements. We particularly study flags that are coarser than the analysis resolution. We find that such RFI flags produce excess power in the EoR window in much the same way…

Instrumentation and Methods for Astrophysics · Physics 2022-01-12 Michael J. Wilensky , Bryna J. Hazelton , Miguel F. Morales

Polarization induced by cosmological scalar perturbations leads to a typical anisotropy pattern, which can best be analyzed in Fourier domain. This allows one to unambiguously distinguish cosmological signal of polarization from other…

Astrophysics · Physics 2009-10-28 Uros Seljak
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