Constraining Globular Cluster Formation Through Studies of Young Massive
  Clusters - IV. Testing the Fast Rotating Massive Star Scenario
  One of the leading models for the formation of multiple stellar populations
within globular clusters is the "Fast Rotating Massive Star" (FRMS) scenario,
where the ejecta of rapidly rotating massive stars is mixed with primordial
material left over from the star-formation process, to form a second generation
of stars within the decretion discs of the high mass stars. A requirement of
this model, at least in its current form, is that young massive (i.e.
proto-globular) clusters are not able to eject the unused gas and dust from the
star-formation process from the cluster for 20-30 Myr after the formation of
the first generation of stars, i.e. the cluster remains embedded within the gas
cloud in which it forms. Here, we test this prediction by performing a
literature search for young massive clusters in nearby galaxies, which have
ages less than 20 Myr that are not embedded. We report that a number of such
clusters exist, with masses near, or significantly above 10^6 Msun, with ages
between a few Myr and ~15 Myr, suggesting that even high mass clusters are able
to clear any natal gas within them within a few Myr after formation.
Additionally, one cluster, Cluster 23 in ESO~338-IG04, has a metallicity below
that of some Galactic globular clusters that have been found to host multiple
stellar populations, mitigating any potential effect of differences in
metallicity in the comparison. The clusters reported here are in contradiction
to the expectations of the FRMS scenario, at least in its current form.
