Radio Continuum Sources behind the Large Magellanic Cloud

Authors

Thomas G. Pannuti

Document Type

Article

Publication Date

7-26-2021

Abstract

We present a comprehensive multi-frequency catalogue of radio sources behind the Large Magellanic Cloud (LMC) between 0.2 and 20 GHz, gathered from a combination of new and legacy radio continuum surveys. This catalogue covers an area of 144 deg2 at angular resolutions from 45 arcsec to 3 arcmin. We find 6 434 discrete radio sources in total, of which 3 789 are detected at two or more radio frequencies. We estimate the median spectral index (; where 𝑆𝑣 𝜈) of 𝛼 = 09 and mean of 088 0.48 for 3 636 sources detected exclusively at two frequencies (0.843 and 1.384 GHz) with similar resolution (Full Width at Half-Maximum (FWHM) 40–45 arcsec). The large frequency range of the surveys makes it an effective tool to investigate Gigahertz Peak Spectrum (GPS), Compact Steep Spectrum (CSS) and Infrared Faint Radio sources populations within our sample. We find 10 GPS candidates with peak frequencies near 5 GHz, from which we estimate their linear size. 1 866 sources from our catalogue are CSS candidates with 08.We found six candidates for High Frequency Peaker (HFP) sources, whose radio fluxes peak above 5 GHz and no sources with unconstrained peaks and ¡ 05. We found optical counterparts for 343 of the radio continuum sources, of which 128 have a redshift measurement. Finally, we investigate the population of 123 Infrared Faint Radio Sources (IFRSs) found in this study.

Recommended Citation

Monthly Notices of the Royal Astronomical Society, 507(2), 2885–2904.