A MeerKAT 1.28 GHz Atlas of Southern Sources in the IRAS Revised Bright Galaxy Sample

TL;DR

This paper presents a detailed radio survey of southern bright galaxies from the IRAS RBGS using MeerKAT at 1.28 GHz, achieving high resolution and sensitivity to study star-forming galaxies.

Contribution

The study provides the first high-resolution, sensitive radio images of all southern IRAS RBGS sources, revealing faint disk emission and precise positions.

Findings

High-resolution radio images of 298 galaxies.

Detection of faint disk emission in many sources.

Precise positional accuracy of about 1 arcsecond.

Abstract

The IRAS Revised Bright Galaxy Sample (RBGS) comprises galaxies and unresolved mergers stronger than $S = 5.24$ Jy at $\lambda = 60~\mu\mathrm{m}$ with galactic latitudes $\vert b \vert > 5^\circ$. Nearly all are dusty star-forming galaxies whose radio continuum and far-infrared luminosities are proportional to their current rates of star formation. We used the MeerKAT array of 64 dishes to make $5 \times 3$ min snapshot observations at $\nu = 1.28$ GHz covering all 298 southern (J2000 $\delta < 0^\circ$) RBGS sources identified with external galaxies. The resulting images have $\theta \approx 7.5$ arcsec FHWM resolution and rms fluctuations $\sigma \approx 20~\mu\mathrm{Jy~beam}^{-1} \approx 0.26$ K, low enough to reveal even faint disk emission. The rms position uncertainties are $\sigma_\alpha \approx \sigma_\delta \approx 1$ arcsec relative to accurate near-infrared positions, and the image dynamic ranges are DR $\gtrsim 10^4:1$.