The role of collision speed, cloud density, and turbulence in the
  formation of young massive clusters via cloud-cloud collisions
  Young massive clusters (YMCs) are recently formed astronomical objects with
unusually high star formation rates. We propose the collision of giant
molecular clouds (GMCs) as a likely formation mechanism of YMCs, consistent
with the YMC conveyor-belt formation mode concluded by other authors. We
conducted smoothed particle hydrodynamical simulations of cloud-cloud
collisions and explored the effect of the clouds' collision speed, initial
cloud density, and the level of cloud turbulence on the global star formation
rate and the properties of the clusters formed from the collision. We show that
greater collision speed, greater initial cloud density and lower turbulence
increase the overall star formation rate and produce clusters with greater
cluster mass. In general, collisions with relative velocity $\gtrsim 25$ km/s,
initial cloud density $\gtrsim 250$ cm$^{-3}$, and turbulence of $\approx 2.5$
km/s can produce massive clusters with properties resembling the observed Milky
Way YMCs.
