English
Related papers

Related papers: The HERA-19 Commissioning Array: Direction Depende…

200 papers

Foregrounds with polarization states that are not smooth functions of frequency present a challenge to HI Epoch of Reionization (EoR) power spectrum measurements if they are not cleanly separated from the desired Stokes I signal. The…

Instrumentation and Methods for Astrophysics · Physics 2018-12-26 Zachary E. Martinot , James E. Aguirre , Saul A. Kohn , Immanuel Q. Washington

Current-generation low frequency interferometers constructed with the objective of detecting the high-redshift 21 cm background, aim to generate power spectra of the brightness-temperature contrast of neutral hydrogen in primordial…

Instrumentation and Methods for Astrophysics · Physics 2016-06-01 S. A. Kohn , J. Aguirre , C. Nunhokee , G. Bernardi , J. Pober , Z. Ali , R. Bradley , C. Carilli , D. DeBoer , N. Gugliucci , D. Jacobs , P. Klima , D. MacMahon , J. Manley , D. Moore , A. Parsons , I. Stefan , W. Walbrugh

Experiments aimed at detecting highly-redshifted 21 centimeter emission from the Epoch of Reionization (EoR) are plagued by the contamination of foreground emission. A potentially important source of contaminating foregrounds may be…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-13 David F. Moore , James E. Aguirre , Aaron R. Parsons , Daniel C. Jacobs , Jonathan C. Pober

Detecting cosmological signals from the Epoch of Reionization (EoR) requires high-precision calibration to isolate the cosmological signals from foreground emission. In radio interferometery, perturbed primary beams of antenna elements can…

The 21 cm hyperfine transition of neutral hydrogen offers a promising probe of the large scale structure of the universe before and during the Epoch of Reionization, when the first ionizing sources formed. Bright radio emission from…

Instrumentation and Methods for Astrophysics · Physics 2020-04-22 Adam E. Lanman , Jonathan C. Pober , Nicholas S. Kern , Eloy de Lera Acedo , David R. DeBoer , Nicolas Fagnoni

The detection of the Epoch of Reionization (EoR) delay power spectrum using a "foreground avoidance method" highly depends on the instrument chromaticity. The systematic effects induced by the radio-telescope spread the foreground signal in…

We construct foreground simulations comprising spatially correlated extragalactic and diffuse Galactic emission components and calculate the `intrinsic' (instrument-free) two-dimensional spatial power spectrum and the cylindrically and…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Peter H. Sims , Lindley Lentati , Paul Alexander , Chris L. Carilli

Unaccounted for systematics from foregrounds and instruments can severely limit the sensitivity of current experiments from detecting redshifted 21~cm signals from the Epoch of Reionization (EoR). Upcoming experiments are faced with a…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 Nithyanandan Thyagarajan , Aaron Parsons , David DeBoer , Judd Bowman , Aaron Ewall-Wice , Abraham Neben , Nipanjana Patra

Radio interferometers aiming to measure the power spectrum of the redshifted 21 cm line during the Epoch of Reionisation (EoR) need to achieve an unprecedented dynamic range to separate the weak signal from overwhelming foreground…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-12 Pascal M. Keller , Bojan Nikolic , Nithyanandan Thyagarajan , Chris L. Carilli , Gianni Bernardi , Ntsikelelo Charles , Landman Bester , Oleg M. Smirnov , Nicholas S. Kern , Joshua S. Dillon , Bryna J. Hazelton , Miguel F. Morales , Daniel C. Jacobs , Aaron R. Parsons , Zara Abdurashidova , Tyrone Adams , James E. Aguirre , Paul Alexander , Zaki S. Ali , Rushelle Baartman , Yanga Balfour , Adam P. Beardsley , Tashalee S. Billings , Judd D. Bowman , Richard F. Bradley , Philip Bull , Jacob Burba , Steven Carey , Carina Cheng , David R. DeBoer , Eloy de Lera Acedo , Matt Dexter , Nico Eksteen , John Ely , Aaron Ewall-Wice , Nicolas Fagnoni , Randall Fritz , Steven R. Furlanetto , Kingsley Gale-Sides , Brian Glendenning , Deepthi Gorthi , Bradley Greig , Jasper Grobbelaar , Ziyaad Halday , Jacqueline N. Hewitt , Jack Hickish , Austin Julius , MacCalvin Kariseb , Joshua Kerrigan , Piyanat Kittiwisit , Saul A. Kohn , Matthew Kolopanis , Adam Lanman , Paul La Plante , Adrian Liu , Anita Loots , Yin-Zhe Ma , David Harold Edward MacMahon , Lourence Malan , Cresshim Malgas , Keith Malgas , Bradley Marero , Zachary E. Martinot , Andrei Mesinger , Mathakane Molewa , Tshegofalang Mosiane , Steven G. Murray , Abraham R. Neben , Hans Nuwegeld , Robert Pascua , Nipanjana Patra , Samantha Pieterse , Jonathan C. Pober , Nima Razavi-Ghods , James Robnett , Kathryn Rosie , Mario G. Santos , Peter Sims , Craig Smith , Hilton Swarts , Pieter Van Wyngaarden , Peter K. G. Williams , Haoxuan Zheng

Combining the visibilities measured by an interferometer to form a cosmological power spectrum is a complicated process. In a delay-based analysis, the mapping between instrumental and cosmological space is not a one-to-one relation.…

The primary challenge for experiments measuring the neutral hydrogen power spectrum from the Epoch of Reionization (EoR) are mode-mixing effects where foregrounds from very bright astrophysical sources interact with the instrument to…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Bryna J. Hazelton , Miguel F. Morales , Ian S. Sullivan

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

The power spectrum of redshifted 21 cm emission brightness temperature fluctuations is a powerful probe of the Epoch of Reionization (EoR). However, bright foreground emission presents a significant impediment to its unbiased recovery from…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-31 Peter H. Sims , Jonathan C. Pober

Detection of the 21-cm signal coming from the epoch of reionization (EoR) is challenging especially because, even after removing the foregrounds, the residual Stokes $I$ maps contain leakage from polarized emission that can mimic the…

Contamination from instrumental effects interacting with bright astrophysical sources is the primary impediment to measuring Epoch of Reionization and BAO 21 cm power spectra---an effect called mode-mixing. In this paper we identify four…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Miguel F. Morales , Bryna Hazelton , Ian Sullivan , Adam Beardsley

Leakage of diffuse polarized emission into Stokes I caused by the polarized primary beam of the instrument might mimic the spectral structure of the 21-cm signal coming from the epoch of reionization (EoR) making their separation difficult.…

Contamination due to foregrounds (Galactic and Extra-galactic), calibration errors and ionospheric effects pose major challenges in detection of the cosmic 21 cm signal in various Epoch of Reionization (EoR) experiments. We present the…

Instrumentation and Methods for Astrophysics · Physics 2018-05-15 B. K. Gehlot , L. V. E. Koopmans , A. G. de Bruyn , S. Zaroubi , M. A. Brentjens , K. M. B. Asad , M. Hatef , V. Jelic , M. Mevius , A. R. Offringa , V. N. Pandey , S. Yatawatta

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
‹ Prev 1 2 3 10 Next ›