Radio Properties of Young Stellar Objects in the Core of the Serpens South Infrared Dark Cloud

TL;DR

This study uses deep radio observations combined with infrared data to identify and characterize young stellar objects in the Serpens South cloud, revealing new protostars and confirming known classifications.

Contribution

First detailed radio study of Serpens South's core, identifying new protostars and confirming classifications with multi-wavelength data.

Findings

Detected approximately eighteen radio sources, seven of which are protostellar.

Identified a previously undetected embedded Class 0 protostar.

Found consistency between radio luminosity and bolometric luminosity for YSOs.

Abstract

We present deep radio continuum observations of the star-forming core of the Serpens South Infrared Dark Cloud with the Karl G. Jansky Very Large Array (VLA). Observations were conducted in two bands centered at 7.25 GHz (4.14 cm) and 4.75 GHz (6.31 cm) with an rms of 8.5 and 11.1 microJy/beam, respectively. We also use 2MASS, Spitzer and Herschel data to put our radio observations in the context of young stellar populations characterized by near and far infrared observations. Within a 5 arcmin x 5 arcmin region of interest around the central cluster, we detect roughly eighteen radio sources, seven of which we determine are protostellar in nature due to their radio spectral indices and their association with infrared sources. We find evidence for a previously undetected embedded Class 0 protostar and reaffirm Class 0 protostellar classifications determined by previous millimeter wavelength continuum studies. We use our infrared data to derive mid-infrared luminosities for three of our protostellar sources and find relative agreement between the known YSO radio luminosity vs bolometric luminosity correlation. Lastly, we marginally detect an additional six radio sources at the 2-3 sigma level that lie within two arcseconds of infrared YSO candidates, providing motivation for higher sensitivity studies to clarify the nature of these sources and further probe embedded and/or low luminosity YSOs in Serpens South.