In the last few years we have been deeply involved in the study of a
handful of
OB star forming regions. In particular, we have concentrated on the search
for
circumstellar accretion disks and toroids. Among the others, one object
stands
unique: the hypercompact HII region G24.78+0.08 A1, ionised by an O9.5 star
and
located at a distance of 7.7 kpc. Interferometric observations have
provided us
evidence of infall in the circumstellar rotating toroid that is enshrouding
this
luminous star. Besides being one of the rare direct detections of infall in
a
young high-mass star, our finding is important for the simultaneous
presence of
three elements in the same massive object: a rotating, collapsing toroid, a
bipolar outflow, ejected along the rotation axis, and a hypercompact
ionised
HII region. The large accretion rate and the existence of a hypercompact
HII
region confirm that the accretion cannot be spherically symmetric and must
occur in a circumstellar disk.
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