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arXiv · 1911.05079

Supernovae within Pre-existing Wind-Blown Bubbles: Dust Injection vs. Ambient Dust Destruction

Abstract

By means of 3-D hydrodynamical simulations, here we evaluate the impact that supernova explosions occurring within wind-driven bubbles have on the survival or destruction of dust grains. We consider both, the dust generated within the ejecta and the dust initially present in the ambient gas and later locked-up in the surrounding wind-driven shell. The collision of the supernova blast wave with the wind-driven shell leads to a transmitted shock that moves into the shell and a reflected shock into the ejecta. The transmitted shock is capable of destroying large amounts of the dust locked in the shell, but only if the mass of the wind-driven shell is small, less than a few tens the ejected mass. Conversely, massive wind-driven shells, with several times the ejected mass, lead upon the interaction to strong radiative cooling, which inhibits the Sedov-Taylor phase and weakens the transmitted shock, making it unable to traverse the wind-driven shell. In such a case, the destruction/disruption of the ambient dust is largely inhibited. On the other hand, the SNRs grow rapidly in the very tenuous region excavated by the stellar winds, and thus a large fraction of the dust generated within the ejecta is not efficiently destroyed by the supernova reverse shock, nor by the reflected shock. Our calculations favor a scenario in which core-collapse supernovae within sufficiently massive wind-driven shells supply more dust to the ISM than what they are able to destroy.

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Sergio Martínez-González, Richard Wünsch, Sergiy Silich, Guillermo Tenorio-Tagle, Jan Palouš, Andrea Ferrara. 2019-11-12. Supernovae within Pre-existing Wind-Blown Bubbles: Dust Injection vs. Ambient Dust Destruction. https://doi.org/10.3847/1538-4357%2Fab571b

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