Does slow and steady win the race? Investigating feedback processes in
  giant molecular clouds
  We investigate the effects of gradual heating on the evolution of turbulent
molecular clouds of mass $2\times 10^6$ M$_\odot$ and virial parameters ranging
between $0.7-1.2$. This gradual heating represents the energy output from
processes such as winds from massive stars or feedback from High Mass X-ray
binaries (HMXBs), contrasting the impulsive energy injection from supernovae
(SNe). For stars with a mass high enough that their lifetime is shorter than
the life of the cloud, we include a SN feedback prescription. Including both
effects, we investigate the interplay between slow and fast forms of feedback
and their effectiveness at triggering/suppressing star formation. We find that
SN feedback can carve low density chimneys in the gas, offering a path of least
resistance for the energy to escape. Once this occurs the more stable, but less
energetic, gradual feedback is able to keep the chimneys open. By funneling the
hot destructive gas away from the centre of the cloud, chimneys can have a
positive effect on both the efficiency and duration of star formation.
Moreover, the critical factor is the number of high mass stars and SNe (and any
subsequent HMXBs) active within the free-fall time of each cloud. This can vary
from cloud to cloud due to the stochasticity of SN delay times and in HMXB
formation. However, the defining factor in our simulations is the efficiency of
the cooling, which can alter the Jeans mass required for sink particle
formation, along with the number of massive stars in the cloud.
