Simulated predictions for H i at z = 3.35 with the Ooty Wide Field Array – I. Instrument and the foregrounds

Marthi, Visweshwar Ram ; Chatterjee, Suman ; Chengalur, Jayaram N ; Bharadwaj, Somnath (2017) Simulated predictions for H i at z = 3.35 with the Ooty Wide Field Array – I. Instrument and the foregrounds Monthly Notices of the Royal Astronomical Society, 471 (3). pp. 3112-3126. ISSN 0035-8711

Full text not available from this repository.

Official URL: http://doi.org/10.1093/mnras/stx1796

Related URL: http://dx.doi.org/10.1093/mnras/stx1796

Abstract

Foreground removal is the most important step in detecting the large-scale redshifted H I 21-cm signal. Modelling foreground spectra is challenging and is further complicated by the chromatic response of the telescope. We present a multifrequency angular power spectrum (MAPS) estimator for use in a survey for redshifted H I 21-cm emission from z ∼ 3.35 and demonstrate its ability to accurately characterize the foregrounds. This survey will be carried out with the two wide-field interferometer modes of the upgraded Ooty Radio Telescope, called the Ooty Wide Field Array (OWFA), at 326.5 MHz. We have tailored the two-visibility correlation for OWFA to estimate the MAPS and test it with simulated foregrounds. In the process, we describe a software model that encodes the geometry and the details of the telescope and simulates a realistic model for the bright radio sky. This article presents simulations  that include the full chromatic response of the telescope in addition to the frequency dependence intrinsic to the foregrounds. We find that the visibility correlation MAPS estimator recovers the input angular power spectrum accurately and that the instrument response to the foregrounds dominates the systematic errors in the recovered foreground power spectra.

Item Type:Article
Source:Copyright of this article belongs to The Royal Astronomical Society.
Keywords:Instrumentation: Interferometers; Methods: Data Analysis; Techniques: Interferometric; Dark Energy, Diffuse Radiation; Large-scale Structure Of Universe, Cosmology: Observations.
ID Code:116298
Deposited On:09 Apr 2021 04:29
Last Modified:09 Apr 2021 04:29

Repository Staff Only: item control page