Molecular jet emission and a spectroscopic survey of S235AB

TL;DR

This study confirms the presence of a molecular jet in S235AB through SiO emission analysis and characterizes its molecular environment, revealing a hot core stage in star formation.

Contribution

It provides the first molecular jet confirmation in S235AB and detailed molecular environment analysis using spectroscopic survey data.

Findings

Detection of high-velocity SiO emission indicating a jet.

Characterization of molecular environment as a hot core.

Derived physical parameters like opacities and temperatures.

Abstract

Context. The S235AB star forming region houses a massive young stellar object which has recently been reported to exhibit possible evidence of jet rotation - an illusive yet crucial component of disk aided star formation theories. Aims. To confirm the presence of a molecular counterpart to the jet and to further study the molecular environment in in S235AB. Methods. We search for velocity wings in the line emission of thermal SiO (J=2-1, v=0), a tracer of shocked gas, which would indicate the presence of jet activity. Utilising other lines detected in our survey we use the relative intensities of intra species transitions, isotopes and hyperfine transitions to derive opacities, temperatures, column densities and abundances of various molecular species in S235AB. Results. The SiO (J=2-1, v=0) emission exhibits velocity wing of up to 75 km/s above and below the velocity of the star, indicating the presence of a jet. The molecular environment describes an evolutionary stage resemblant of a hot molecular core.