The Chemistry of Cosmic Dust Analogues from C, C₂, and C₂H₂ in C-Rich Circumstellar Envelopes.

ABSTRACT: Interstellar carbonaceous dust is mainly formed in the innermost regions of circumstellar envelopes around carbon-rich asymptotic giant branch (AGB) stars. In these highly chemically stratified regions, atomic and diatomic carbon, along with acetylene are the most abundant species after H₂ and CO. In a previous study, we addressed the chemistry of carbon (C and C₂) with H₂ showing that acetylene and aliphatic species form efficiently in the dust formation region of carbon-rich AGBs whereas aromatics do not. Still, acetylene is known to be a key ingredient in the formation of linear polyacetylenic chains, benzene and polycyclic aromatic hydrocarbons (PAHs), as shown by previous experiments. However, these experiments have not considered the chemistry of carb

SUBMITTER: Santoro G 

PROVIDER: S-EPMC7116318 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature