Name: Aishrila Mazumder
Affiliation: Indian Institute of Technology Indore
Conference ID : ASI2022_571
Title : A GMRT Survey of Lockman Hole Field at 325 MHz
Authors : Aishrila Mazumder, Abhirup Datta
Abstract Type: Poster
Abstract Category : Extragalactic Astronomy
Abstract : This work presents the findings from a 325 MHz survey of the Lockman Hole region using the legacy GMRT archive. The frequency used is of interest for studying astrophysics of radio selected sources, and also for foreground studies pertinent to post-EoR observations. It covers a field of view of 6 deg^2, with a sensitivity limit of 50 micro-Jy/beam. Source counts for compact sources with fluxes above 6 times the background RMS has been determined. Two point correlation functions for both spatial and angular scales have also been studied. The results for two point correlation function agrees with previous observations. However, there is also some deviations from the detailed semi-empirical SKADS simulation in the terms of the bias parameter and clustering length. This points towards the requirement for more low frequency observations to provide better constraints on underlying cosmology controlling the evolution of matter in the Universe, as well as for development of better models of the radio sky. Angular power spectrum has also been determined for the diffuse emission present in the region. The value of the power obtained lies between 1-100 mK^2, which is very high compared to the expected strength of the cosmological 21-cm signal. This shows that even at locations far away from the galactic plane, diffuse synchrotron emission from the Galaxy pose a major hurdle for sensitive radio observations from the early Universe.