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arXiv · 2311.11213

Diverse features of dust particles and their aggregates inferred from experimental nanoparticles

Yuki Nakano·Yuki Kimura·Akihiko Hashimoto
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Abstract

Nanometre- to micrometre-sized solid dust particles play a vital role in star and planet formations. Despite of their importance, however, our understanding of physical and chemical properties of dust particles is still provisional. We have conducted a condensation experiment of the vapour generated from a solid starting material having nearly cosmic proportions in elements. A laser flash heating and subsequent cooling has produced a diverse type of nanoparticles simultaneously. Here we introduce four types of nanoparticles as potential dust particles in space: amorphous silicate nanoparticles (type S); core/mantle nanoparticles with iron or hydrogenised-iron core and amorphous silicate mantle (type IS); silicon oxycarbide nanoparticles and hydrogenised silicon oxycarbide nanoparticles (type SiOC); and carbon nanoparticles (type C), all produced in a single heating-cooling event. Type IS and SiOC nanoparticles are new for potential astrophysical dust. The nanoparticles are aggregated to a wide variety of structures, from compact, fluffy, and networked. A simultaneous formation of nanoparticles, which are diverse in chemistry, shape, and structure, prompts a re-evaluation of astrophysical dust particles

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Yuki Nakano, Yuki Kimura, Akihiko Hashimoto. 2023-11-19. Diverse features of dust particles and their aggregates inferred from experimental nanoparticles. https://arxiv.org/abs/2311.11213

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