English
Related papers

Related papers: Mitigating Internal Instrument Coupling II: A Meth…

200 papers

There are few data available with which to constrain the thermal history of the intergalactic medium (IGM) following global recombination. Thus far, most constraints flow from analyses of the Cosmic Microwave Background and optical…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-10 L. J. Greenhill , G. Bernardi

The redshifted 21-cm signal from neutral hydrogen (HI) in the intergalactic medium (IGM) is a powerful probe of the Epoch of Reionization (EoR). Owing to the complex growth and morphology of ionized regions, the 21-cm brightness-temperature…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Vishrut Pandya , Leon Noble , Suman Majumdar , Debanjan Sarkar , Mohd Kamran , Abhirup Datta

Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by reducing foreground sensitivity while linking ionization morphology to galaxies. We quantify the constraining power of 21cm-Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yannic Pietschke , Anne Hutter , Caroline Heneka

We explore methods for robust estimation of the 21 cm signal from the Epoch of Reionisation (EoR). A Kernel Density Estimator (KDE) is introduced for measuring the spatial temperature fluctuation power spectrum from the EoR. The KDE…

The epoch of reionization power spectrum is expected to evolve strongly with redshift, and it is this variation with cosmic history that will allow us to begin to place constraints on the physics of reionization. The primary obstacle to the…

We model the distribution of neutral hydrogen (HI) in the post-reionization era and investigate its detectability in 21 cm intensity mapping with the future SKA radio telescope. We rely on high resolution hydrodynamical N-body simulations.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Francisco Villaescusa-Navarro , Matteo Viel , Kanan K. Datta , T. Roy Choudhury

Observation of redshifted 21-cm signals from neutral hydrogen holds the key to understanding the structure formation and its evolution during the reionization and post-reionization era. Apart from the presence of orders of magnitude larger…

Instrumentation and Methods for Astrophysics · Physics 2022-03-02 Jais Kumar , Prasun Dutta , Samir Choudhuri , Nirupam Roy

The central challenge in 21~cm cosmology is isolating the cosmological signal from bright foregrounds. Many separation techniques rely on the accurate knowledge of the sky and the instrumental response, including the antenna primary beam.…

We present the first limits on the Epoch of Reionization (EoR) 21-cm HI power spectra, in the redshift range $z=7.9-10.6$, using the Low-Frequency Array (LOFAR) High-Band Antenna (HBA). In total 13\,h of data were used from observations…

Accurate modelling of the primary beam is an important but difficult task in radio astronomy. For high dynamic range problems such as 21cm intensity mapping, small modelling errors in the sidelobes and spectral structure of the beams can…

Instrumentation and Methods for Astrophysics · Physics 2024-07-25 Michael J. Wilensky , Jacob Burba , Philip Bull , Hugh Garsden , Katrine A. Glasscock , Nicolas Fagnoni , Eloy de Lera Acedo , David R. DeBoer , Nima Razavi-Ghods

We present a formalism to extract the EoR HI power spectrum for drift scans using radio interferometers. Our main aim is to determine the coherence time scale of time-ordered visibilities. We compute the two-point correlation function of…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-08 Akash Kumar Patwa , Shiv Sethi

We present a sophisticated statistical point-source foreground model for low-frequency radio Epoch of Reionization (EoR) experiments using the 21 cm neutral hydrogen emission line. Motivated by our understanding of the low-frequency radio…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Steven G. Murray , Cathryn M. Trott , Christopher H. Jordan

We quantify the effect of radio frequency interference (RFI) on measurements of the 21-cm power spectrum during the Epoch of Reionization (EoR). Specifically, we investigate how the frequency structure of RFI source emission generates…

Instrumentation and Methods for Astrophysics · Physics 2020-09-09 Michael J. Wilensky , Nichole Barry , Miguel F. Morales , Bryna J. Hazelton , Ruby Byrne

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

Using a combination of N-body simulations, semi-analytic models and radiative transfer calculations, we have estimated the theoretical cross power spectrum between galaxies and the 21cm emission from neutral hydrogen during the epoch of…

The upcoming Square Kilometre Array Low Frequency (SKA-Low) interferometer will have the required sensitivity to detect the 21 cm line from neutral hydrogen during the Epoch of Reionisation (EoR). In preparation, we investigated the…

Instrumentation and Methods for Astrophysics · Physics 2025-09-25 E. Jong , C. Trott , C. D. Nunhokee , Q. Zheng

We introduce a new method for performing robust Bayesian estimation of the three-dimensional spatial power spectrum at the Epoch of Reionization (EoR), from interferometric observations. The versatility of this technique allows us to…

Instrumentation and Methods for Astrophysics · Physics 2018-11-06 Peter H. Sims , Lindley Lentati , Jonathan C. Pober , Chris Carilli , Michael P. Hobson , Paul Alexander , Paul Sutter

The 21~cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation. The main difficulty in measuring the 21 cm signal is the presence of bright foregrounds that require very accurate…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-20 N. Charles , G. Bernardi , H. L. Bester , O. M. Smirnov , C. Carilli , P. M. Keller , N. Kern , B. Nikolic , N. Thyagarajan , E. de Lera Acedo , N. Fagnoni , M. G. Santos

Interferometric experiments of the reionization era offer the advantages of measuring power in spatial modes with increased sensitivity afforded by multiple independent sky measurements. Here we review early work to measure this signal,…

Instrumentation and Methods for Astrophysics · Physics 2019-09-30 Cathryn M. Trott , Jonathan C. Pober

We explore the possibility of constraining model parameters of the Epoch of Reionization (EoR) from 21cm brightness temperature maps, using a combination of morphological descriptors constructed from the eigenvalues of the Contour Minkowski…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Akanksha Kapahtia , Pravabati Chingangbam , Raghunath Ghara , Stephen Appleby , Tirthankar Roy Choudhury
‹ Prev 1 4 5 6 7 8 10 Next ›