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arXiv · 1906.04369

The Formation of Bimodal Dust Species in Nova Ejecta I: Chemical Conditions

Chunhua Zhu·Helei Liu·Guoliang Lü·Zhaojun Wang·Lin Li
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Abstract

The formation of bimodal dust species (that is, both of silicate and amorphous carbon dust grains are observed in a nova eruption) in nova ejecta is still debated. Using the Modules for Experiments in Stellar Astrophysics code and considering the effects of WD's mass, mass-accretion rate and the chemical profiles of WD which are described by new parameter --- mixing depth on the chemical abundances of nova ejecta, we investigate the possibility that bimodal dust species are produced in a nova eruption. We find that $C/O$ (the ratio of carbon number density to oxygen number density) of nova ejecta is affected by the mixing depth. For the model with a small mixing depth, the $C/O$ of nova ejecta can evolute from lager than 1.0 to smaller than 1.0 in a whole eruption, which provides the chemical condition for the formation of bimodal dust species.

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Chunhua Zhu, Helei Liu, Guoliang Lü, Zhaojun Wang, Lin Li. 2019-06-11. The Formation of Bimodal Dust Species in Nova Ejecta I: Chemical Conditions. https://doi.org/10.1093/mnras%2Fstz1638

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