English
Related papers

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

200 papers

We investigate the possibility of detecting the 3D cross correlation power spectrum of the Ly-$\alpha$ forest and HI 21 cm signal from the post reionization epoch. The cross-correlation signal is directly dependent on the dark matter power…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Tapomoy Guha Sarkar , Kanan K. Datta

The current status of the HI simulation efforts is presented, in which a self consistent simulation path is described and basic equations to calculate array sensitivities are given. There is a summary of the SKA Design Study (SKADS) sky…

Instrumentation and Methods for Astrophysics · Physics 2010-02-03 H. R. Kloeckner , R. Auld , I. Heywood , D. Obreschkow , F. Levrier , S. Rawlings

Upcoming galaxy surveys with the SKA Observatory will detect neutral hydrogen (HI) across unprecedented volumes, and their scientific return will crucially depend on predictive models for HI observables. In this work, we present a framework…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Joël Mayor , Marta Spinelli , Gabriella De Lucia , Robert Yates , Alexandre Refregier , Fabio Fontanot , Lizhi Xie , Michaela Hirschmann

Accurate beam modeling is important in many radio astronomy applications. In this paper, we focus on beam modeling for 21-cm intensity mapping experiments using radio interferometers, though the techniques also apply to single dish…

Instrumentation and Methods for Astrophysics · Physics 2025-09-16 Michael J. Wilensky , Philip Bull , Nicolas Fagnoni

Observations of the high-redshift Universe using the 21 cm line of neutral hydrogen and complimentary emission lines from the first galaxies promise to open a new door for our understanding of the epoch of reionization. We present…

Astrophysics of Galaxies · Physics 2019-03-13 Sebastian Dumitru , Girish Kulkarni , Guilaine Lagache , Martin G. Haehnelt

It has been proposed recently that the SKA1-MID could be used to conduct an HI intensity mapping survey that could rival upcoming Stage IV dark energy surveys. However, measuring the weak HI signal is expected to be very challenging due to…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-01 Stuart E. Harper , Clive Dickinson , Richard Battye , Lucas Olivari

A large fraction of baryons predicted from the standard cosmology has been missing observationally. Although previous numerical simulations have indicated that most of the missing baryons reside in large-scale filaments in the form of Warm…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Toshihiro Horii , Shinsuke Asaba , Kenji Hasegawa , Hiroyuki Tashiro

We study the behavior of internal signal chain reflections and antenna cross coupling as systematics for 21 cm cosmological surveys. We outline the mathematics for how these systematics appear in interferometric visibilities and describe…

Instrumentation and Methods for Astrophysics · Physics 2019-10-28 Nicholas S. Kern , Aaron R. Parsons , Joshua S. Dillon , Adam E. Lanman , Nicolas Fagnoni , Eloy de Lera Acedo

The 21 cm signal arising from fluctuations in the neutral hydrogen field, and its cross-correlation with other tracers of cosmic density, are promising probes of the high-redshift Universe. In this study, we assess the potential of the 21…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Barun Maity

We present detailed predictions for the redshifted 21cm signal from the epoch of reionization. These predictions are obtained from radiative transfer calculations on the results of large scale (100/h Mpc), high dynamic range, cosmological…

Astrophysics · Physics 2009-11-11 Garrelt Mellema , Ilian T. Iliev , Ue-Li Pen , Paul R. Shapiro

After reionization, neutral hydrogen (HI) traces the large-scale structure (LSS) of the Universe, enabling HI intensity mapping (IM) to capture the LSS in 3D and constrain key cosmological parameters. We present a new framework utilizing…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-10 Eishica Chand , Arka Banerjee , Simon Foreman , Francisco Villaescusa-Navarro

Prior to the epoch of reionisation, the 21-cm signal of the cosmic dawn is dominated by the Lyman-$\alpha$ coupling and gas temperature fluctuations caused by the first sources of radiation. While early efforts to model this epoch relied on…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-05 Aurel Schneider , Sambit K. Giri , Jordan Mirocha

We present a comprehensive methodology for the simulation of astronomical images from optical survey telescopes. We use a photon Monte Carlo approach to construct images by sampling photons from models of astronomical source populations,…

The Epoch of Reionization (EoR) neutral Hydrogen (HI) 21-cm signal evolves significantly along the line-of-sight (LoS) due to the light-cone (LC) effect. It is important to accurately incorporate this in simulations in order to correctly…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-13 Suman Pramanick , Rajesh Mondal , Somnath Bharadwaj

The sky-averaged (global) highly redshifted 21-cm spectrum from neutral hydrogen is expected to appear in the VHF range of $\sim20-200$ MHz and its spectral shape and strength are determined by the heating properties of the first stars and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-24 Keith Tauscher , David Rapetti , Jack O. Burns , Eric R. Switzer

[Abridged] The spatially averaged global spectrum of the redshifted 21cm line has generated much experimental interest, for it is potentially a direct probe of the Epoch of Reionization and the Dark Ages. Since the cosmological signal here…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-07 Adrian Liu , Jonathan R. Pritchard , Max Tegmark , Abraham Loeb

21cm intensity mapping experiments aim to observe the diffuse neutral hydrogen (HI) distribution on large scales which traces the Cosmic structure. The Square Kilometre Array (SKA) will have the capacity to measure the 21cm signal over a…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Laura Wolz , Filipe B. Abdalla , David Alonso , Chris Blake , Philip Bull , Tzu-Ching Chang , Pedro G. Ferreira , Cheng-Yu Kuo , Marios G. Santos , Richard Shaw

Accurate simulations of the 21-cm signal from the Epoch of Reionization require the generation of maps at specific frequencies given the values of astrophysical and cosmological parameters. The peculiar velocities of the hydrogen atoms…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Emma Chapman , Mario G. Santos

While simulation tools for visible light communication (VLC) with photo detectors (PDs) have been widely investigated, similar tools for optical camera communication (OCC) with complementary metal oxide semiconductor (CMOS) sensors are…

Signal Processing · Electrical Eng. & Systems 2025-04-15 Srivathsan Chakaravarthi Narasimman , Arokiaswami Alphones

The 21 cm signal contains a wealth of information about the formation of the first stars and the reionization of the intergalactic medium during the Cosmic Dawn (CD) and Epoch of Reionization (EoR). The timing of these important milestones…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-15 Nadia Cooper , Carina Norregaard , Romain Meriot , Jonathan R. Pritchard