Discovery of the Pure Polycyclic Aromatic Hydrocarbon Indene (c-C9H8) with GOTHAM Observations of TMC-1

@article{Burkhardt2021DiscoveryOT,
  title={Discovery of the Pure Polycyclic Aromatic Hydrocarbon Indene (c-C9H8) with GOTHAM Observations of TMC-1},
  author={Andrew M. Burkhardt and Kin Long Kelvin Lee and P. Bryan Changala and Christopher N. Shingledecker and Ilsa R. Cooke and Ryan A. Loomis and Hongji Wei and Steven B. Charnley and Eric Herbst and Michael C. McCarthy and Brett A. McGuire},
  journal={The Astrophysical Journal Letters},
  year={2021},
  volume={913}
}
Polycyclic aromatic hydrocarbons (PAHs) have long been invoked in the study of interstellar and protostellar sources, but the unambiguous identification of any individual PAH has proven elusive until very recently. As a result, the formation mechanisms for this important class of molecules remain poorly constrained. Here we report the first interstellar detection of a pure hydrocarbon PAH, indene (C9H8), as part of the GBT Observations of TMC-1: Hunting for Aromatic Molecules (GOTHAM) survey… 

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