A photoionized accretion disk around a young high-mass star

TL;DR

This study provides high-resolution ALMA observations revealing a photo-ionized accretion disk around a young high-mass star, demonstrating disk survival despite intense stellar feedback and suggesting binary formation.

Contribution

First direct observational evidence of a photo-ionized accretion disk around a high-mass young star using ALMA data.

Findings

Detection of a rotating, photo-ionized accretion disk around the HMYSO.

Evidence that disks can survive photo-ionization feedback.

Identification of a nearby low-mass young stellar object indicating potential binary formation.

Abstract

We present high spatial resolution ($52$ au) observations of the high-mass young stellar object (HMYSO) G345.4938+01.4677 made using the Atacama Large Millimeter/sub-millimeter Array (ALMA). This O-type HMYSO is located at 2.38 kpc and it is associated with a luminosity of $1.5\times10^5 L_\odot$. We detect circumstellar emission from the H$38\beta$ hydrogen recombination line showing a compact structure rotating perpendicularly to the previously detected radio jet. We interpret this emission as tracing a photo-ionized accretion disk around the HMYSO. While this disk-like structure seems currently too small to sustain continued accretion, the data present direct observational evidence of how disks can effectively survive the photo-ionization feedback from young high-mass stars. We also report the detection of a low-mass young stellar object in the vicinity of the HMYSO and suggest that it forms a high-mass and low-mass star binary system.