Number counts, confusion, mapping issues and sky coverage analysis for radio continuum surveys through EMU Early Science, EMU-ASKAP, and WODAN especially for cosmology science goals

TL;DR

This paper analyzes challenges such as noise, confusion, and mapping issues in radio continuum surveys like EMU-ASKAP and WODAN, assessing their impact on cosmological science goals including ISW effect detection.

Contribution

It provides a detailed evaluation of technical and data analysis challenges in current and future radio surveys relevant for cosmology.

Findings

Identifies key issues affecting survey sensitivity and accuracy.

Assesses impact of mapping problems on cosmological measurements.

Offers insights for improving future radio continuum surveys.

Abstract

Looking deep into the space in search for truth has been a long time goal of humanity. With the development of new technologies and observational techniques, we are now well equipped to see objects billions of light years away from us. In this study we are going to discuss some of the challenges radio astronomers face while observing radio continuum sources. We will discuss issues related to rms noise, confusion, position accuracy, shot noise and how these issues can affect observation results, data analysis and the science goals we are trying to achieve. We will mainly focus on the Evolutionary Map of the Universe (EMU-ASKAP) sky survey, EMU Early science survey and Westerbork Observations of the Deep APERTIF Northern sky (WODAN), for our study. The study will also be useful for future surveys like with possible continuum surveys through MeerKAT (e.g. MIGHTEE) and SKA-1. The late time Integrated Sachs-Wolfe (ISW) effect detection is one of the major areas of research related to dark energy cosmology. We will particularly discuss how technical, data analysis and mapping issues, affect galaxy over/under density dependent science goals like the detection of the late time Integrated Sachs-Wolfe (ISW) effect through wide field radio continuum surveys.