Detection of Interstellar CH3

  title={Detection of Interstellar CH3},
  author={Helmut Feuchtgruber and Frank P. Helmich and Ewine F. van Dishoeck and Christopher M. Wright},
  journal={The Astrophysical Journal Letters},
  pages={L111 - L114}
Observations with the Short Wavelength Spectrometer on board the Infrared Space Observatory have led to the first detection of the methyl radical CH3 in the interstellar medium. The ν2 Q-branch at 16.5 μm and the R(0) line at 16.0 μm have been unambiguously detected toward the Galactic center Sagittarius A*. The analysis of the measured bands gives a column density of (8.0 ± 2.4) × 1014 cm-2 and an excitation temperature of 17 ± 2 K. Gaseous CO at a similarly low excitation temperature and C2H2… 

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