Mortality and dust expulsion in early phases of stellar clusters

Abstract

Context. It is often argued that young stellar clusters suffer a significant infant mortality that is partly related to the expulsion of dust and gas in their early phases caused by radiation pressure from hot stars and supernovae. Near-infrared (J − K)− M K diagrams of young stellar clusters in nearby spiral galaxies show a bi-modal distribution that is consistent with a fast decline of their intrinsic extinction at an early epoch. Aims. The distinct features in the color-magnitude diagrams (CMD) and the fast change of colors for the youngest clusters allow us to place constraints on their early evolutionary phases, including the time scale for the decreasing extinction caused for instance by gas and dust expulsion. Methods. Monte Carlo simulations of cluster populations were performed using the power-law distribution function g(M, τ) ∝ M α τ γ . Integrated colors were computed from Starburst99 models. The simulated near-infrared CMD were compared with those observed for six grand-design, spiral galaxies using statistical goodness-of-fit tests.

Studying the YMC population of M83: how long clusters remain embedded, their interaction with the ISM and implications for GC formation theories

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Probing the Dragonfish star-forming complex: the ionizing population of the young massive cluster Mercer 30

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High-velocity blueshifted Fe ii absorption in the dwarf star-forming galaxy PHL 293B: evidence for a wind driven supershell?

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