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Related papers: An analytical method to simulate the HI 21-cm visi…

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We introduce simulations aimed at assessing how well weak gravitational lensing of 21cm radiation from the Epoch of Reionization ($z \sim 8$) can be measured by an SKA-like radio telescope. A simulation pipeline has been implemented to…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-21 Alessandro Romeo , R. Benton Metcalf , Alkistis Pourtsidou

We describe a new software package for simulating channelised, high-time resolution data streams from radio telescopes. The software simulates data from the telescope and observing system taking into account the observation strategy,…

Instrumentation and Methods for Astrophysics · Physics 2022-05-09 Rui Luo , George Hobbs , Suk Yee Yong , Andrew Zic , Lawrence Toomey , Shi Dai , Alex Dunning , Di Li , Tommy Marshman , Chen Wang , Pei Wang , Shuangqiang Wang , Songbo Zhang

We present an investigation of the horizon and its effect on global 21-cm observations and analysis. We find that the horizon cannot be ignored when modeling low frequency observations. Even if the sky and antenna beam are known exactly,…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Neil Bassett , David Rapetti , Keith Tauscher , Bang D. Nhan , David D. Bordenave , Joshua J. Hibbard , Jack O. Burns

Microwave cavity haloscopes are among the most sensitive direct detection experiments searching for dark matter axions via their coupling to photons. When the power of the expected microwave signal due to axion-photon conversion is on the…

Instrumentation and Detectors · Physics 2023-10-10 Yuqi Zhu , M. J. Jewell , Claire Laffan , Xiran Bai , Sumita Ghosh , Eleanor Graham , S. B. Cahn , Reina H. Maruyama , S. K. Lamoreaux

Experimental 21 cm cosmology aims to detect the formation of the first stars during the cosmic dawn and the subsequent epoch of reionization by utilizing the 21 cm hydrogen line transition. While several experiments have published results…

Instrumentation and Methods for Astrophysics · Physics 2024-09-23 John Cumner , Carla Pieterse , Dirk De Villiers , Eloy de Lera Acedo

Optical coherence tomography (OCT) is a widely used imaging technique in the micrometer regime, which gained accelerating interest in medical imaging in the last twenty years. In up-to-date OCT literature [5,6] certain simplifying…

Medical Physics · Physics 2024-02-23 Leopold Veselka , Lisa Krainz , Leonidas Mindrinos , Wolfgang Drexler , Peter Elbau

We have studied the possibility of measuring the cross-correlation of the redshifted HI 21-cm signal and the Lyman-$\alpha$ forest using an upcoming radio-interferometric array OWFA and an spectroscopic observation like SDSS-IV. Our results…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Anjan Kumar Sarkar , Somnath Bharadwaj , Tapomoy Guha Sarkar

We introduce a novel technique, called "granulometry", to characterize and recover the mean size and the size distribution of HII regions from 21-cm tomography. The technique is easy to implement, but places the previously not very well…

Line-intensity mapping of the 21cm line is a powerful probe of large scale structure at z<6, tracing large-scale structure via neutral hydrogen content that is found within galaxies. In principle, it enables cost-efficient surveys of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-20 Adrian Liu , Simon Foreman , Hamsa Padmanabhan , H. Cynthia Chiang , Seth Siegel , Dallas Wulf , Jonathan Sievers , Matt Dobbs , Keith Vanderlinde

We present an analytic formulation to model the fluctuating component of the HI signal from the epoch of reionization during the phase of partial heating. During this phase, we assume self-ionized regions, whose size distribution can be…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-14 Janakee Raste , Shiv Sethi

The {\rm HI} 21-cm intensity mapping signal experiences redshift space distortions due to the motion of the galaxies which contain the {\rm HI} as well as the motions of the {\rm HI} gas within the galaxies. A detailed modelling is…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-19 Debanjan Sarkar , Somnath Bharadwaj

The HI 21cm absorption line is masked by bright foregrounds and systematic distortions that arise due to the chromaticity of the antenna used to make the observation coupling to the spectral inhomogeneity of these foregrounds. We…

Instrumentation and Methods for Astrophysics · Physics 2021-11-12 Dominic Anstey , Eloy de Lera Acedo , Will Handley

Reliable and exact assessment of visibility is essential for safe air traffic. In order to overcome the drawbacks of the currently subjective reports from human observers, we present an approach to automatically derive visibility measures…

Computer Vision and Pattern Recognition · Computer Science 2015-05-21 Jean-Philippe Andreu , Stefan Mayer , Karlheinz Gutjahr , Harald Ganster

Observations of redshifted 21cm radiation from HI at high redshifts is an important future probe of reionization. We consider the Multi-frequency Angular Power Spectrum (MAPS) to quantify the statistics of the HI signal as a joint function…

Astrophysics · Physics 2008-11-26 Kanan K. Datta , T. Roy Choudhury , Somnath Bharadwaj

Upcoming 21-cm intensity surveys will use the hyperfine transition in emission to map out neutral hydrogen in large volumes of the universe. Unfortunately, large spatial scales are completely contaminated with spectrally smooth…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-27 Chirag Modi , Martin White , Anze Slosar , Emanuele Castorina

The sky-averaged (global) 21-cm signal is a powerful probe of the intergalactic medium (IGM) prior to the completion of reionization. However, it has so far been unclear that even in the best case scenario, in which the signal is accurately…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Jordan Mirocha , Geraint J. A. Harker , Jack O. Burns

We develop an effective perturbation theory (and, equivalently, a bias expansion) for the inhomogeneous 21cm radiation field from reionization. Using large-scale simulations of cosmological reionization, we find that this expansion…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-20 Matthew McQuinn , Anson D'Aloisio

We use full sky simulations, including the effects of foreground contamination and removal, to explore multi-tracer synergies between a SKA-like 21cm intensity mapping survey and a LSST-like photometric galaxy redshift survey. In particular…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Amadeus Witzemann , David Alonso , José Fonseca , Mario G. Santos

Aperture array interferometers, such as that proposed for the Square Kilometre Array (SKA), will see the entire sky, hence the standard approach to simulating visibilities will not be applicable since it relies on a tangent plane…

Astrophysics · Physics 2008-09-11 J. D. McEwen , A. M. M. Scaife

Intensity mapping of the neutral hydrogen (HI) is a new observational tool that can be used to efficiently map the large-scale structure of the Universe over wide redshift ranges. The power spectrum of the intensity maps contains…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 L. Wolz , C. Tonini , C. Blake , J. S. B. Wyithe
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