Study of the dense molecular gas surrounding the "Extended Green Object" G35.03+0.35

TL;DR

This study investigates the molecular gas and outflows surrounding the massive young stellar object G35.03+0.35, revealing active outflow phenomena, dense molecular envelopes, and multiple young stellar objects in the region.

Contribution

It provides new observational evidence of molecular outflows and dense gas in the vicinity of G35.03+0.35, using multi-line submillimeter data and spectral energy distribution analysis.

Findings

Detected molecular outflows with 30 M_sun mass and 3000 M_sun (km/s)^2 kinetic energy.

Identified dense molecular clumps supporting active star formation.

Confirmed the object as a very early-stage massive young stellar object.

Abstract

We present the results of a new study of the molecular gas associated with the "extended green object" (EGO) G35.03+0.35. This object, very likely a massive young stellar object, is embedded in a molecular cloud at the border of an HII region. The observations were performed with the Atacama Submillimeter Telescope Experiment (ASTE) in the 12CO and 13CO J=3-2, HCO+ J=4-3, and CS J=7-6 lines with an angular resolution about 22". From the 12CO J=3-2 line we discovered outflowing activity of the massive young stellar object. We obtained a total mass and kinetic energy for the outflows of 30 M_sun and 3000 M_sun (km/s)^2 (6 x 10^{46} ergs), respectively. We discovered a HCO+ and CS clump towards the EGO G35.03+0.35. The detection of these molecular species supports the presence of molecular outflows and a dense molecular envelope with temperatures and densities above 40 K and 6 x 10^{6} cm^{-3}, respectively. Using public near- and mid-IR, and sub-mm data we investigated the spectral energy distribution confirming that EGO G35.03+0.35 is a massive young stellar object at the earliest evolutionary stage (i.e. a class I young stellar object). By anlysing radio continuum archival data we found three radio sources towards the object, suggesting the presence of several young stellar objects in the region. Our radio continuum analysis is consistent with the presence of at least one ultracompact HII region and an hypercompact HII region or a constant-velocity ionized wind source.