The impact of UV photons from a stellar companion on the chemistry of AGB outflows. Issue Volume 16:Issue S366(2020) (November 2020)

• Record Type: Journal Article
• Authors: Van de Sande, M.; Millar, T. J.
• Editors: Decin, Leen; Zijlstra, Albert; Gielen, Clio
• Is Part Of: Proceedings of the International Astronomical Union. Volume 16:Issue S366(2020)
• Page Start: 265
• Page End: 270
• Publication Date: 2020-11
• Subjects: Stars: AGB and post-AGB -- circumstellar matter -- astrochemistry -- molecular processes; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921322000138
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: Binary interaction with a stellar or planetary companion has been proposed to be the driving mechanism behind large-scale asymmetries, such as spirals and disks, observed within AGB outflows. We developed the first chemical kinetics model that takes the effect of a stellar companions's UV radiation into account. The presence of a stellar companion can initiate a rich photochemistry in the inner wind. Its impact is determined by the intensity of the UV radiation and the extinction the radiation experiences. The outcome of the inner wind photochemistry depends on the balance between two-body reactions and photoreactions. If photoreactions dominate, the outflow can appear molecule-poor. If two-body reactions dominate, chemical complexity within the outflow can increase, yielding daughter species with a large inner wind abundance. A comprehensive view on the molecular content of the outflow, especially combined with abundance profiles, can point towards the presence of a stellar companion.