PI: Kimberly Sokal, University of Virginia, email@example.com
Address: Astronomy Department, P.O. Box 400325, Charlottesville, VA 22904-4325, USA
CoI: Kelsey Johnson, University of Virginia
CoI: Philip Massey, Lowell Observatory
CoI: Remy Indebetouw, University of Virginia
Title: Emerging Wolf-Rayet Stars in Embedded Super Star Clusters
Abstract: The formation of massive stars, especially when clustered, can alter galaxy energetics. The presence of even a few Wolf-Rayet stars (WRs) can drastically impact a young massive star cluster's evolution and may be critical in removing natal gas. However, the impact on the star formation environment of the cluster is not well understood. Observing young massive clusters will provide insight into their formation timescales and evolution, possibly driven by WRs whose short lifespans provide tight age constraints. We target one of the earliest stages of massive star clusters, detectable via thermal free-free radio emission resulting from optically thick natal material enshrouding the cluster, termed Ultra-Dense HII regions (UDHIIs). We hypothesize that the most massive stars may evolve into WRs while the cluster is still embedded and be revealed as their strong winds blow away the natal material, resulting in an important and brief phase in cluster evolution. We propose to obtain optical spectra of embedded UDHIIs in various galaxies to identify WR populations. Contrasting the clusters will enable the identification of the stages of early cluster evolution, providing insight into the stages when Wolf-Rayet stars can be detected and their effects on the surrounding material.
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