| Name: | Saswata Dasgupta |
| Affiliation: | Indian Institute of Technology, Indore |
| Conference ID : | ASI2023_247 |
| Title : | Analysing HI 21-cm maps from the EoR via future SKA1-Low observations using the largest cluster statistics |
| Authors : | Saswata Dasgupta, Samit Kumar Pal, Satadru Bag, Suman Majumdar, Abhirup Datta, Sohini Dutta |
| Mode of Presentation: | Poster |
| Abstract Category : | General Relativity and Cosmology |
| Abstract : | We attempt to determine the nature of the ionizing sources and the astrophysical
processes going on in the Intergalactic Medium (IGM) during the Epoch of Reionization
(EoR). We analyse the evolution of the largest ionized region using the topological and
morphological evolution of neutral hydrogen distribution during the different stages of EoR.
For this analysis we use the Largest Cluster Statistics - LCS. The simulated HI 21cm maps
from EoR are first scaled down to a lower resolution, after which they are contaminated
with simulated Gaussian noise with varying RMS values from ∼ 3.10?? to ∼ 9.30??
in accordance with the upcoming Square Kilometer Array in its low frequency regime
observations, namely the SKA1-low. After that, the beam’s impact was simulated using a
3D Gaussian kernel of varying length scales, merged into the maps, and the images were
then examined using LCS. Finally, to test the robustness further, the maps were run through
an OSKAR pipeline that mimics the behaviour of SKA1-low and then cleaned using an
advanced CLEAN algorithm using CASA. We see that although the features of the maps can
be recovered using advanced cleaning algorithms but the percolation transition point gets
heavily shifted due to the effect of resolution and the effect of the beam which may lead to an
incorrect interpretation of the reionization history. This leads to the inference that it would
require denser ? − ? coverage at higher baseline distances for SKA1-Low to be able to do
image analyses like LCS. |
