Related papers: The GMRT Search for Reionization
Simulated maps of the HI distribution in the post-reionization era are used to study the prospects for detection with existing and upcoming radio telescopes. We consider detection in the redshifted radiation from the hyperfine transition…
Fast radio bursts (FRB) probe the electron density of the universe along the path of propagation, making high redshift FRB sensitive to the helium reionization epoch. We analyze the signal to noise with which a detection of the amplitude of…
Foreground subtraction is the biggest challenge for future redshifted 21 cm observations to probe reionization. We use a short GMRT observation at 153 MHz to characterize the statistical properties of the background radiation across ~ one…
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,…
Observing the first galaxies formed during the reionisation epoch, i.e. approximately within the first billion years after the Big Bang, remains one of the challenges of contemporary astrophysics. Several efforts are being undertaken to…
The detection of individual ionized bubbles in HI 21-cm maps is one of the most promising, direct probes of the epoch of reionization(EoR). Atleast 1000 hrs of observation would be required for such a detection with either the currently…
Limiting the number of model-dependent assumptions to a minimum, we discuss the detectability of the sources responsible for reionization with existing and planned telescopes. We conclude that if reionization sources are UV-efficient,…
Radio frequency interference (RFI) have been an enduring concern in radio astronomy, particularly for the observations of pulsars which require high timing precision and data sensitivity. In most works of the literature, RFI mitigation has…
To determine the epoch of reionization precisely and to reveal the property of inhomogeneous reionization are some of the most important topics of modern cosmology. Existing methods to investigate reionization which use cosmic microwave…
In the next decade, radio telescopes like the Square Kilometer Array (SKA) will explore the Universe at high redshift, and particularly during the Epoch of Reionisation (EoR). The first structures emerged during this epoch, and their…
We discuss the effect of dispersion delay due to intervening ionized media in the radio emission of gamma-ray bursts (GRBs). For high redshift GRBs ($z \ga 3$), the ionized intergalactic medium (IGM) should be the dominant source of…
A real-time broadband RFI mitigation system has been developed for the Upgraded GMRT (uGMRT). Here, we report the engineering, imaging, and beam/pulsar results from the test observations in all the bands of the uGMRT during the monsoon of…
For the GMRT, we calculate the expected signal from redshifted HI emission at two frequency bands centered at 610 and 325 MHz. The study focuses on the visibility-visibility cross-correlations, proposed earlier as the optimal statistical…
The GMRT reionization effort aims to map out the large scale structure of the Universe during the epoch of reionization (EoR). Removal of polarized Galactic emission is a difficult part of any 21 cm EoR program, and we present new upper…
Direct detection of the Dark Ages and the Epoch of Reionization (EOR) is among the main scientific objectives of all current and future low-frequency radio facilities. In this paper we summarize and discuss recent results, based on…
Recent years have seen major advances in understanding the state of the intergalactic medium (IGM) at high redshift. Some aspects of this understanding are reviewed here. In particular, we discuss: (1) Different probes of IGM like…
The search for the electromagnetic counterparts to gravitational wave (GW) events has been rapidly gathering pace in recent years thanks to the increasing number and capabilities of both gravitational wave detectors and wide field survey…
Fast radio burst (FRB) discoveries are occurring rapidly, with thousands expected from upcoming surveys. The dispersion measures (DM) observed for FRB include important information on cosmological distances and the ionization state of the…
RFI mitigation is a critically important issue in radio astronomy using existing instruments as well as in the development of next-generation radio telescopes, such as the Square Kilometer Array (SKA). Most designs for the SKA involve…
Radio astronomy observational facilities are under constant upgradation and development to achieve better capabilities including increasing the time and frequency resolutions of the recorded data, and increasing the receiving and recording…