Radio-Continuum study of the Nearby Sculptor Group Galaxies. Part 1: NGC 300 at lambda = 20 cm

TL;DR

This study presents high-resolution, sensitive radio-continuum images of NGC 300, revealing extended emission and new sources, and compares imaging techniques to optimize data quality.

Contribution

It introduces a new mosaic imaging approach for NGC 300 at 20 cm, highlighting the advantages of immerge over joint deconvolution.

Findings

Extended radio-continuum emission differs from optical appearance

Discovery of previously unidentified discrete sources

Immerge approach yields better image quality than joint deconvolution

Abstract

A series of new radio-continuum (lambda=20 cm) mosaic images focused on the NGC 300 galactic system were produced using archived observational data from the VLA and/or ATCA. These new images are both very sensitive (rms=60 microJy) and feature high angular resolution (<10"). The most prominent new feature is the galaxy's extended radio-continuum emission, which does not match its optical appearance. Using these newly created images a number of previously unidentified discrete sources have been discovered. Furthermore, we demonstrate that a joint deconvolution approach to imaging this complete data-set is inferior when compared to an immerge approach.