Carina's Pillars of Destruction: the view from ALMA
  Forming high-mass stars have a significant effect on their natal environment.
Their feedback pathways, including winds, outflows, and ionising radiation,
shape the evolution of their surroundings which impacts the formation of the
next generation of stars. They create or reveal dense pillars of gas and dust
towards the edges of the cavities they clear. They are modelled in feedback
simulations, and the sizes and shapes of the pillars produced are consistent
with those observed. However, these models predict measurably different
kinematics which provides testable discriminants. Here we present the first
ALMA Compact Array (ACA) survey of 13 pillars in Carina, observed in $^{12}$CO,
$^{13}$CO and C$^{18}$O J=2-1, and the 230 GHz continuum. The pillars in this
survey were chosen to cover a wide range in properties relating to the amount
and direction of incident radiation, proximity to nearby irradiating clusters
and cloud rims, and whether they are detached from the cloud. With these data,
we are able to discriminate between models. We generally find pillar velocity
dispersions of $<$ 1 km s$^{-1}$ and that the outer few layers of molecular
emission in these pillars show no significant offsets from each other,
suggesting little bulk internal motions within the pillars. There are instances
where the pillars are offset in velocity from their parental cloud rim, and
some with no offset, hinting at a stochastic development of these motions.
