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arXiv · 1610.07318

Visible absorptions of potential diffuse ISM hydrocarbons: C$_9$H$_9$ and C$_9$H$_5$ radicals

Mathias Steglich·Surajit Maity·John P. Maier
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Abstract

The laboratory detection of previously unobserved resonance-stabilized C$_9$H$_5$ and C$_9$H$_9$ radicals in the supersonic expansion of a hydrocarbon discharge source is reported. The radicals are tentatively assigned as acetylenic-substituted cyclopentadienyl C$_9$H$_5$ and vinyl-substituted benzyl C$_9$H$_9$ species. They are found to feature visible absorption bands that coincide with a few very weak diffuse interstellar bands toward HD183143 and HD204827.

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Mathias Steglich, Surajit Maity, John P. Maier. 2016-10-24. Visible absorptions of potential diffuse ISM hydrocarbons: C$_9$H$_9$ and C$_9$H$_5$ radicals. https://doi.org/10.3847/0004-637x%2F830%2F2%2F145

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