Searching for Molecular Jets from High-Mass Protostars

TL;DR

This study uses VLA observations to detect SiO emission in high-mass protostar candidates, confirming molecular jets in 60% of the sample and revealing correlations with source luminosities.

Contribution

First detection of SiO emission associated with molecular jets in high-mass protostars using VLA, confirming jet nature in a majority of candidates.

Findings

SiO emission detected in 6 out of 10 sources

60% of jet candidates confirmed as molecular jets

Positive correlation between SiO luminosity and source luminosities

Abstract

We report Very Large Array (VLA) observations in the Q-band toward 10 ionized jet candidates to search for SiO emission, a well-known shocked gas tracer. We detected 7 mm continuum counterparts toward 90% of the jet candidates. In most cases, the jet candidate is located toward the center of the 7 mm core, and the high masses ($\approx 100\,M_\odot$) and densities ($\approx 10^7\, \text{cm}^{-3}$) of the cores suggest that the central objects are very young high-mass protostars. We detected SiO $J=1-0$ emission associated with 6 target sources. In all cases, the morphology and spectrum of the emission is consistent with what is expected for molecular jets along an outflow axis, thus confirming the jet nature of 60% of our sample. Our data suggest a positive correlation between the SiO luminosity $L_{SiO}$, and both the bolometric luminosity $L_{Bol}$ and the radio luminosity $S_\nu d^2$ of the driving sources.