CONTAMINATION BY SUPERNOVAE IN GLOBULAR CLUSTERS

Credit: ALMA (ESO/NAOJ/NRAO)/Alexandra Angelich (NRAO/AUI/NSF)

Only a small amount of the supernovae products remains trapped within globular clusters and this "catch" only occurs in the most massive cases (mass cluster ≥ 10^6 solar masses).
In smaller clusters instead there is no contamination by supernovae (supernova explosions produce heavier elements such as iron, gold, etc.). A group of astrophysicists has shown that the shock wave and the metals produced by supernovae disperse outside the cluster. This inhibits the gas contamination used by the first stellar generation (a new stellar generation can arise from the "recycled gas" expelled by supernovae). Only the material ejected by the supernova at the center of a massive cluster remain trapped (the ejected material moves in a high-density medium and remains locked) and it is available to a stellar population of second generation.

To know more
http://arxiv.org/abs/1511.02918
http://iopscience.iop.org/article/10.1088/2041-8205/814/1/L8/pdf

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