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arXiv · 0705.0639

Hydrocarbon anions in interstellar clouds and circumstellar envelopes

T. J. Millar·C. Walsh·M. A. Cordiner·R. Ní Chuimín·Eric Herbst
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Abstract

The recent detection of the hydrocarbon anion C6H- in the interstellar medium has led us to investigate the synthesis of hydrocarbon anions in a variety of interstellar and circumstellar environments. We find that the anion/neutral abundance ratio can be quite large, on the order of at least a few percent, once the neutral has more than five carbon atoms. Detailed modeling shows that the column densities of C6H- observed in IRC+10216 and TMC-1 can be reproduced. Our calculations also predict that other hydrocarbon anions, such as C4H- and C8H-, are viable candidates for detection in IRC+10216, TMC-1 and photon-dominated regions such as the Horsehead Nebula.

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T. J. Millar, C. Walsh, M. A. Cordiner, R. Ní Chuimín, Eric Herbst. 2007-05-07. Hydrocarbon anions in interstellar clouds and circumstellar envelopes. https://doi.org/10.1086/519376

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