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arXiv · 1809.11032

Maximally dusty star-forming galaxies: Supernova dust production and recycling in Local Group and high-redshift galaxies

Abstract

Motivated by recent observations suggesting that core-collapse supernovae may on average produce ~0.3 M_sun of dust, we explore a simple dust production scenario which applies to star-forming galaxies in the local environment (the Magellanic Clouds and possibly the Milky Way) as well as to high redshift (sub- millimeter, QSO, Lyman break) galaxies. We assume that the net dust destruction (due to supernova reverse shock, shocks in the interstellar medium, or astration) is negligible on a timescale of 1 Gyr, in which case the dust mass can be estimated as 0.004 times the star-formation rate (for a Chabrier IMF) multiplied by the duration of the star-formation episode. The model can account for observed dust masses over four orders of magnitude and across the redshift range 0-8.4, with dust production rates spanning five orders of magnitudes. This suggests that star-forming galaxies may be seen as maximally dusty, in the sense that a dominant fraction of the dust-forming elements forged in a supernova eventually will go into the solid phase. In turn, this indicates little destruction of supernova dust or almost complete replenishment, on a short time scale, of any dust that is destroyed.

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Christa Gall, Jens Hjorth. 2018-09-28. Maximally dusty star-forming galaxies: Supernova dust production and recycling in Local Group and high-redshift galaxies. https://doi.org/10.3847/1538-4357/aae520

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