English
Related papers

Related papers: Constraining Reionization Morphology and Source Pr…

200 papers

Mapping of the neutral hydrogen (HI) 21-cm intensity fluctuations across redshifts promises a novel and powerful probe of cosmology. The neutral hydrogen gas mass density, $\Omega_{\rm HI}$ and bias parameter, $b_{\rm HI}$ are key…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-10 Hamsa Padmanabhan , T. Roy Choudhury , Alexandre Refregier

Weak gravitational lensing of the CMBR manifests as a secondary anisotropy in the temperature maps. The effect, quantified through the shear and convergence fields imprint the underlying large scale structure (LSS), geometry and evolution…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-19 Tapomoy Guha Sarkar

We discuss the possibility of performing blind surveys to detect large-scale features of the universe using 21cm emission. Using instruments with approx. 5'-10' resolution currently in the planning stage, it should be possible to detect…

Astrophysics · Physics 2008-11-26 Richard A. Battye , Rod D. Davies , Jochen Weller

Detecting neutral Hydrogen (H\,{\sc i}) via the 21~cm line emission from the intergalactic medium at $z\gtrsim 6$ has been identified as one of the most promising probes of the epoch of cosmic reionization -- a major phase transition of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Nithyanandan Thyagarajan , Chris Carilli , Bojan Nikolic

The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and HIRAX experiments,…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Dionysios Karagiannis , Roy Maartens , Liantsoa Randrianjanahary

Observations of the redshifted 21-cm line during the Epoch of Reionization will open a new window to probe the intergalactic medium during the formation of the first stars, galaxies, and black holes. A particularly promising route to an…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-10 Kai-Feng Chen , Meredith Neyer , Jacqueline N. Hewitt , Aaron Smith , Mark Vogelsberger

We explore the ability of observations of the global brightness temperature of the 21-cm signal to constrain the reionization history and the properties of the ionizing sources. In order to describe the reionization signal, we employ either…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Andrea Morandi , Rennan Barkana

The emission from neutral hydrogen (HI) clouds in the post-reionization era (z < 6), too faint to be individually detected, is present as a diffuse background in all low frequency radio observations below 1420 MHz. The angular and frequency…

Astrophysics · Physics 2009-10-29 Somnath Bharadwaj , Shiv K. Sethi , Tarun Deep Saini

We present new constraints on the 21cm Epoch of Reionization (EoR) power spectrum derived from 3 months of observing with a 32-antenna, dual-polarization deployment of the Donald C. Backer Precision Array for Probing the Epoch of…

The Minkowski Functionals (MFs), a set of topological summary statistics, have emerged as a powerful tool for extracting non-Gaussian information. We investigate the prospect of constraining the reionization parameters using the MFs of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Kangning Diao , Zhaoting Chen , Xuelei Chen , Yi Mao

We present new measurements of the intensity of the ionizing ultraviolet background and the global emissivity of ionizing photons over 2 < z < 5. Our results are based on a suite of updated measurements of physical properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 George D. Becker , James S. Bolton

Motivated by recent progress in studies of the high-$z$ Universe, we build a new model for the global 21-cm signal that is explicitly calibrated to measurements of the galaxy luminosity function (LF) and further tuned to match the Thomson…

Astrophysics of Galaxies · Physics 2016-12-06 Jordan Mirocha , Steven R. Furlanetto , G. Sun

We study the observed cosmic ionizing background as a constraint on the nature of the sources responsible for the reionization of the Universe. In earlier work, we showed that extrapolations of the Ultra-Violet Luminosity Function (LF) of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Fabio Fontanot , Stefano Cristiani , Christoph Pfrommer , Guido Cupani , Eros Vanzella

At redshifts z >~ 30 neutral hydrogen gas absorbs CMB radiation at the 21cm spin-flip frequency. In principle this is observable and a high-precision probe of cosmology. We calculate the linear-theory angular power spectrum of this signal…

Astrophysics · Physics 2008-11-26 Antony Lewis , Anthony Challinor

Of the many probes of reionization, the 21 cm line and the cosmic microwave background (CMB) are among the most effective. We examine how the cross-correlation of the 21 cm brightness and the CMB Doppler fluctuations on large angular scales…

Astrophysics · Physics 2014-02-20 Peter Adshead , Steven Furlanetto

The 21\,cm line and the patchy kinetic Sunyaev-Zel'dovich (kSZ) effect are promising and complementary probes of the Epoch of Reionization (EoR). A challenge for cross-correlating these two signals is that foreground avoidance or removal…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 Meng Zhou , Paul La Plante , Adam Lidz , Yi Mao , Yin-Zhe Ma

A critical challenge in measuring the power spectrum of 21cm emission from cosmic reionization is compensating for the frequency dependence of an interferometer's sampling pattern, which can cause smooth-spectrum foregrounds to appear…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Aaron R. Parsons , Jonathan C. Pober , James E. Aguirre , Christopher L. Carilli , Daniel C. Jacobs , David F. Moore

Understanding properties of the first sources in the Universe using the redshifted \HI ~21-cm signal is one of the major aims of present and upcoming low-frequency experiments. We investigate the possibility of imaging the redshifted 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 Raghunath Ghara , T. Roy Choudhury , Kanan K. Datta , Samir Choudhuri

We present a method to implement the idea of Jain & Taylor to constrain cosmological parameters with weak gravitational lensing. Photometric redshift information on foreground galaxies is used to produce templates of the mass structure at…

Astrophysics · Physics 2008-11-26 G. M. Bernstein , B. Jain

We investigate the impact of neutral hydrogen (HI) in galaxies on the statistics of 21-cm fluctuations using analytic and semi-numerical modelling. Following the reionisation of hydrogen the HI content of the Universe is dominated by damped…

Astrophysics · Physics 2015-05-13 Stuart Wyithe , Lila Warszawski , Paul M. Geil , S. Peng Oh
‹ Prev 1 8 9 10 Next ›