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Related papers: Limits on the 21 cm power spectrum at z=6.5-7.0 fr…

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We compute the spherically-averaged power spectrum from four seasons of data obtained for the Epoch of Reionisation (EoR) project observed with the Murchison Widefield Array (MWA). We measure the EoR power spectrum over $k=…

The compact configuration of Phase II of the Murchison Widefield Array (MWA) consists of both a redundant subarray and pseudo-random baselines, offering unique opportunities to perform sky-model and redundant interferometric calibration.…

Current attempts to measure the 21cm Power Spectrum of neutral hydrogen during the Epoch of Reionization are limited by systematics which produce measured upper limits above both the thermal noise and the expected cosmological signal. These…

We explore the properties of interferometric data from high-redshift 21~cm measurements using the Murchison Widefield Array. These data contain redshifted 21~cm signal, contamination from continuum foreground sources, and radiometric noise.…

We present an analysis of Epoch of Reionization data from Phase II of the Murchison Widefield Array using the \texttt{simpleDS} delay spectrum pipeline. Prior work analyzed the same observations using the FHD/$\varepsilon$ppsilon imaging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Matthew Kolopanis , Jonathan Pober , Daniel C. Jacobs , Samantha McGraw

The Murchison Widefield Array (MWA) team has derived new upper limits on the spherically averaged power spectrum of the 21-cm signal at six redshifts in the range $z \approx 6.5-8.7$. We use these upper limits and a Bayesian inference…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-24 Raghunath Ghara , Sambit K. Giri , Benedetta Ciardi , Garrelt Mellema , Saleem Zaroubi

Measurements of 21 cm Epoch of Reionization (EoR) structure are subject to systematics originating from both the analysis and the observation conditions. Using 2013 data from the Murchison Widefield Array (MWA), we show the importance of…

The radio interferometric closure phases can be a valuable tool for studying cosmological {H\scriptsize{I}}~from the early Universe. Closure phases have the advantage of being immune to element-based gains and associated calibration errors.…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-05 Himanshu Tiwari , Nithyanandan Thyagarajan , Cathryn M. Trott , Benjamin McKinley

The detection of redshifted hyperfine line of neutral hydrogen (HI) is the most promising probe of the Epoch of Reionization (EoR). We report an analysis of 55 hours of Murchison Widefield Array (MWA) Phase II drift scan EoR data. The data…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Akash Kumar Patwa , Shiv Sethi , K. S. Dwarakanath

We present a new upper limit to the 21cm power spectrum during the Epoch of Reionization (EoR) which constrains reionization models with an unheated IGM. The GMRT-EoR experiment is an ongoing effort to make a statistical detection of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Gregory Paciga , Tzu-Ching Chang , Yashwant Gupta , Rajaram Nityanada , Julia Odegova , Ue-Li Pen , Jeffrey Peterson , Jayanta Roy , Kris Sigurdson

We present new upper limits on the 21-cm signal power spectrum from the Epoch of Reionization (EoR), at redshifts $z \approx 10.1, 9.1, \text{ and } 8.3$, based on reprocessed observations from the Low-Frequency Array (LOFAR). The analysis…

Observations in the lowest MWA band between $75-100$ MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift $\sim 13-17$. Using 15 hours of MWA data, we analyse systematics in this…

We report the most sensitive upper limits to date on the 21 cm epoch of reionization power spectrum using 94 nights of observing with Phase I of the Hydrogen Epoch of Reionization Array (HERA). Using similar analysis techniques as in…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-28 The HERA Collaboration , Zara Abdurashidova , Tyrone Adams , James E. Aguirre , Paul Alexander , Zaki S. Ali , Rushelle Baartman , Yanga Balfour , Rennan Barkana , Adam P. Beardsley , Gianni Bernardi , Tashalee S. Billings , Judd D. Bowman , Richard F. Bradley , Daniela Breitman , Philip Bull , Jacob Burba , Steve Carey , Chris L. Carilli , Carina Cheng , Samir Choudhuri , David R. DeBoer , Eloy de Lera Acedo , Matt Dexter , Joshua S. Dillon , John Ely , Aaron Ewall-Wice , Nicolas Fagnoni , Anastasia Fialkov , Randall Fritz , Steven R. Furlanetto , Kingsley Gale-Sides , Hugh Garsden , Brian Glendenning , Adélie Gorce , Deepthi Gorthi , Bradley Greig , Jasper Grobbelaar , Ziyaad Halday , Bryna J. Hazelton , Stefan Heimersheim , Jacqueline N. Hewitt , Jack Hickish , Daniel C. Jacobs , Austin Julius , Nicholas S. Kern , Joshua Kerrigan , Piyanat Kittiwisit , Saul A. Kohn , Matthew Kolopanis , Adam Lanman , Paul La Plante , David Lewis , Adrian Liu , Anita Loots , Yin-Zhe Ma , David H. E. MacMahon , Lourence Malan , Keith Malgas , Cresshim Malgas , Matthys Maree , Bradley Marero , Zachary E. Martinot , Lisa McBride , Andrei Mesinger , Jordan Mirocha , Mathakane Molewa , Miguel F. Morales , Tshegofalang Mosiane , Julian B. Muñoz , Steven G. Murray , Vighnesh Nagpal , Abraham R. Neben , Bojan Nikolic , Chuneeta D. Nunhokee , Hans Nuwegeld , Aaron R. Parsons , Robert Pascua , Nipanjana Patra , Samantha Pieterse , Yuxiang Qin , Nima Razavi-Ghods , James Robnett , Kathryn Rosie , Mario G. Santos , Peter Sims , Saurabh Singh , Craig Smith , Hilton Swarts , Jianrong Tan , Nithyanandan Thyagarajan , Michael J. Wilensky , Peter K. G. Williams , Pieter van Wyngaarden , Haoxuan Zheng

The redshifted cosmological 21 cm signal emitted by neutral hydrogen during the first billion years of the universe is much fainter relative to other galactic and extragalactic radio emissions, posing a great challenge towards detection of…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-26 J. Kariuki Chege , C. H. Jordan , C. Lynch , C. M. Trott , J. L. B. Line , B. Pindor , S. Yoshiura

Several experimental efforts are underway to measure the power spectrum of 21cm fluctuations from the Epoch of Reionization (EoR) using low-frequency radio interferometers. Experiments like the Hydrogen Epoch of Reionization Array (HERA)…

Instrumentation and Methods for Astrophysics · Physics 2019-06-19 Adam E. Lanman , Jonathan C. Pober

We forecast the sensitivity with which the Murchison Widefield Array (MWA) can measure the 21 cm power spectrum of cosmic hydrogen, using radiative transfer simulations to model reionization and the 21 cm signal. The MWA is sensitive to…

Astrophysics · Physics 2009-11-13 Adam Lidz , Oliver Zahn , Matthew McQuinn , Matias Zaldarriaga , Lars Hernquist

The Epoch of Reionization (EoR)---when neutral hydrogen in the intergalactic medium was systematically ionized---is a period in our Universe's history that is currently poorly understood. However, a key prediction of most models is a…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-25 Michael Pagano , Adrian Liu

We report upper-limits on the Epoch of Reionization (EoR) 21 cm power spectrum at redshifts 7.9 and 10.4 with 18 nights of data ($\sim36$ hours of integration) from Phase I of the Hydrogen Epoch of Reionization Array (HERA). The Phase I…

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