Tying the geometrical traits of massive young stellar objects and their discs to a potential evolutionary sequence using infrared observations

TL;DR

This study links the geometrical features of massive young stellar objects and their discs to an evolutionary sequence, revealing that disc evolution occurs within MYSOs similarly to low-mass stars, despite faster formation.

Contribution

It combines spectral and geometrical analyses to propose an evolutionary sequence for MYSO discs, a novel approach in this field.

Findings

Discs with geometrical substructure are more spectroscopically evolved.

Disc evolution and dispersal occur within MYSOs.

Similar disc evolution processes occur in both high-mass and low-mass YSOs.

Abstract

Young massive stars influence their surroundings from local to galactic scales, but the observational challenges associated with their distance and embedded nature has, until the recent decade, made high-resolution studies of these objects difficult. In particular, comparative analyses of massive young stellar object (MYSO) discs are currently lacking and our understanding of their evolution is limited. Here, we combine the results of two studies with the aim to attribute geometrical features to an evolutionary sequence for a sample of seven MYSOs. The time evolution is based on a near-IR spectral features, while the geometry is determined from a multi size-scale study of MYSOs. We find that MYSO discs with determined geometrical substructure turn out to be also spectroscopically more evolved. This implies that disc evolution and dispersal are occurring within MYSOs, similar to low-mass YSO disc evolution, despite their faster formation timescales.