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arXiv · 1006.5466

Dust grain growth in the interstellar medium of 5<z<6.5 quasars

Michał J. Michałowski·Eric J. Murphy·Jens Hjorth·Darach Watson·Christa Gall·James S. Dunlop
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Abstract

We investigate whether stellar dust sources i.e. asymptotic giant branch (AGB) stars and supernovae (SNe) can account for dust detected in 5 5 QSOs, whereas SNe may be able to account for dust in some QSOs. However, they require very high dust yields even for a top-heavy initial mass function. This suggests additional non-stellar dust formation mechanism e.g. significant dust grain growth in the interstellar medium of at least three out of nine z>5 QSOs. SNe (but not AGB stars) may deliver enough heavy elements to fuel this growth.

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Michał J. Michałowski, Eric J. Murphy, Jens Hjorth, Darach Watson, Christa Gall, James S. Dunlop. 2010-06-28. Dust grain growth in the interstellar medium of 5<z<6.5 quasars. https://doi.org/10.1051/0004-6361%2F201014902

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