Molecular processes from the AGB to the PN stage

Abstract

Many complex organic molecules and inorganic solid-state compounds have been observed in the circumstellar shell of stars (both C-rich and O-rich) in the transition phase between Asymptotic Giant Branch (AGB) stars and Planetary Nebulae (PNe). This short (~100-10.000 years) phase of stellar evolution represents a wonderful laboratory for astrochemistry and provides severe constraints on any model of gas-phase and solid-state chemistry. One of the major challenges of present day astrophysics and astrochemistry is to understand the formation pathways of these complex organic molecules and inorganic solid-state compounds (e.g., polycyclic aromatic hydrocarbons, fullerenes, and graphene in the case of a C-rich chemistry and oxides and crystalline silicates in O-rich environments) in space. In this review, I present an observational review of the molecular processes in the late stages of stellar evolution with a special emphasis on the first detections of fullerenes and graphene in PNe.

8 pages, 4 figures, Invited Review in IAU Symposium 283, Planetary Nebulae: An Eye to the Future, eds. Manchado, Stanghellini, and Schoenberner (in press)

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Cited by in corpus (1)

• On the formation of molecules and solid-state compounds from the AGB to the PN phases