Astronomy & Space Sciences
Title : | Ionospheric effect on the redshifted 21-cm radio-interferometric observations with uGMRT and satellite observations |
Area of research : | Astronomy & Space Sciences |
Focus area : | Astrophysics, Radio Astronomy |
Principal Investigator : | Dr. Abhik Ghosh, Banwarilal Bhalotia College, Asansol, West Bengal |
Timeline Start Year : | 2023 |
Timeline End Year : | 2026 |
Contact info : | abhik.physicist@gmail.com |
Details
Executive Summary : | The ionosphere's low-frequency sky is limited by the signal-to-noise ratio of radio interferometers, such as the Giant Metrewave Radio Telescope (GMRT). This project aims to characterize and quantify the effect of systematic errors when radio waves travel through the ionosphere using uGMRT data. The project will use three bright calibrators to isolate ionospheric induced systematic errors during day and night time. GMRT's positional advantage allows it to probe sensitive regions of the ionosphere with higher sensitivity than widely used satellite observations. The large frequency bandwidth of uGMRT will help in separating and correcting these systematic effects. The World Magnetic Model (WMM), differential Faraday rotation, and differential TEC measurements from uGMRT will be used to measure absolute TEC values. Interferometric measurements will be compared with the Global Navigation Satellite System (GNSS) for better time resolution. The statistics of density fluctuations of the ionosphere will be quantified through structure-function analysis. Two-dimensional structure-function models will be used to explore the anisotropy of ionospheric structures. By separating and correcting for systematic effects, such as clock drift, ionospheric delay, and Faraday rotation, calibration degrees of freedom can be reduced for fields not dominated by strong calibrators.
The knowledge gained from uGMRT data can be utilized to provide guidelines for observations and low-frequency data reduction of the upcoming Square Kilometer Array (SKA) telescope. Proper execution of the project can also constrain the intergalactic medium (IGM) and evolution of galaxies at high redshifts via studies of red-shifted 21-cm signals. |
Co-PI: | Dr. Parimal Ghosh, Banwarilal Bhalotia College, Asansol, West Bengal-713303, Dr. Sushanta Kumar Mondal, Sidho-Kanho-Birsha University, Purulia, West Bengal-723104 |
Total Budget (INR): | 22,47,080 |
Organizations involved