Near-Infrared Spectroscopy Towards the H2 Peak in Orion Academic Article uri icon


  • We present cross-dispersed slit spectra of the H2 emission peak in Orion (Peak 1). Relative line intensities are presented for H I, [Fe II], [O I], He I, and H2 lines between 1.25 and 2.3 m. These emission lines are used to determine extinction towards and excitation of the emitting gas. We find that the atomic lines arise in a foreground region of much lower extinction than the H2 lines. The H2 line ratios are consistent with collisionally excited gas at a few thousand degrees and in agreement with some simple shock models. We find no evidence for nonthermal (e.g., fluorescent) excitation in the H2 spectra and show that any fluorescent emission present cannot affect our results significantly. We have also obtained H2 emission-line images over a larger region that includes Peak 1 and discuss how spectra like ours could be used as a diagnostic to determine the types of shocks producing the observed emission. 1995 American Astronomical Society.

published proceedings

  • The Astronomical Journal

author list (cited authors)

  • Everett, M. E., Depoy, D. L., & Pogge, R. W.

citation count

  • 10

complete list of authors

  • Everett, Mark E||Depoy, DL||Pogge, Richard W

publication date

  • September 1995