H2 Pure Rotational Lines in the Orion Bar

@article{Allers2005H2PR,
  title={H2 Pure Rotational Lines in the Orion Bar},
  author={Katelyn Allers and Daniel T. Jaffe and John H. Lacy and Bruce T. Draine and Matthew J. Richter},
  journal={The Astrophysical Journal},
  year={2005},
  volume={630},
  pages={368-380}
}
Photodissociation regions (PDRs), where UV radiation dominates the energetics and chemistry of the neutral gas, contain most of the mass in the dense interstellar medium of our Galaxy. Observations of H2 rotational and rovibrational lines reveal that PDRs contain unexpectedly large amounts of very warm (400-700 K) molecular gas. Theoretical models have difficulty explaining the existence of so much warm gas. Possible problems include errors in the heating and cooling functions or in the… Expand
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