Institution(s): 1. Salisbury University, 2. Space Telescope Science Institute
Stellar populations synthesis models have proven to be excellent tools to learn about galaxy evolution. However, modeling small stellar populations (lower than 105 M⊙) has been an intriguing and continuous to be a field of intensive research. In this work, we have developed a new approach to form stars from clusters first, where massive stars are formed from fractions of mass of small stellar clusters. This new approximation is based on the empirical power law (mc-2) for the mass function of clusters between 20-1100 M⊙ found in recent years and the maximum stellar mass that can be formed in a cluster. Incorporating this new approach to form clusters has made us upgrade the way we integrate the stellar properties and the way that the isochrone is produced with a new technique. To produce the new models we have used the most recent version of Starburst99 that incorporates the most recent stellar evolution models with rotation. On the verge of solving nearby stellar populations and observing small stellar populations across the universe, this new approach brings a new scope on trying to disentangle the nature of hyper and supermassive stars in small stellar populations. In this work we present this new approach and the results when these models are applied to very energetic stellar populations such as the cluster in NGC 3603. Our most important result is that we have modeled the ionizing power of this cluster and some others by forming enough supermassive stars in a cluster of ~104 M⊙.