Supernovae and their expanding blast waves during the early evolution of
  Galactic globular clusters
  Our arguments deal with the early evolution of Galactic globular clusters and
show why only a few of the supernovae products were retained within globular
clusters and only in the most massive cases ($M \ge 10^6$ Msol), while less
massive clusters were not contaminated at all by supernovae. Here we show that
supernova blast waves evolving in a steep density gradient undergo blowout and
end up discharging their energy and metals into the medium surrounding the
clusters. This inhibits the dispersal and the contamination of the gas left
over from a first stellar generation. Only the ejecta from well centered
supernovae, that evolve into a high density medium available for a second
stellar generation in the most massive clusters would be retained. These are
likely to mix their products with the remaining gas, leading in these cases
eventually to an Fe contaminated second stellar generation.
