We present optical spectroscopy observations of 145 high-mass pre-main-sequence
candidates from the catalog of Vioque et al. 2020 From these, we provide evidence for the …

Context. The young massive-star-forming region M17 contains optically visible massive pre-
main-sequence stars that are surrounded by circumstellar disks. Such disks are expected to …

Context. It is a challenge to study the formation process of massive stars: their formation time
is short, there are only few of them, they are often deeply embedded, and they lie at …

Context. Circumstellar discs are essential for the formation of high mass stars, while
multiplicity, and in particular binarity, appears to be an inevitable outcome, as the vast …

Context. Recently much progress has been made in probing the embedded stages of
massive star formation, pointing to formation scenarios that are reminiscent of a scaled-up …

Context. Spectroscopic multiplicity surveys of O stars in young clusters and OB associations
have revealed that a large portion (∼ 70%) of these massive stars (M i> 15 M⊙) belong to …

We have performed a high-resolution 4–13 μm spectral survey of the hot molecular gas
associated with the massive protostars AFGL 2591 and AFGL 2136. Here we present the …

Context. Given the high incidence of binaries among mature field massive stars, it is clear
that multiplicity is an inevitable outcome of high-mass star formation. Understanding how …

Close to 100 per cent of massive stars are thought to be in binary systems. The multiplicity of
massive stars seems to be intrinsically linked to their formation and evolution, and massive …

We present results from a high spectral resolution (6 km s-1) survey of five massive
protostars in the wavelength range of 2.95 and 3.25 µm, conducted with iSHELL at the …