A Spitzer Infrared Spectrograph Detection of Crystalline Silicates in a Protostellar Envelope

  title={A Spitzer Infrared Spectrograph Detection of Crystalline Silicates in a Protostellar Envelope},
  author={Charles A. Poteet and S. Thomas Megeath and Dan Watson and Nuria Calvet and Ian S. Remming and Melissa McClure and B. Sargent and William J. Fischer and Elise Furlan and Lori E. Allen and Jon Eric Bjorkman and Lee Hartmann and J Muzerolle and John J. Tobin and Babar Ali},
  journal={The Astrophysical Journal},
We present the Spitzer Space Telescope Infrared Spectrograph spectrum of the Orion A protostar HOPS-68. The mid-infrared spectrum reveals crystalline substructure at 11.1, 16.1, 18.8, 23.6, 27.9, and 33.6 μm superimposed on the broad 9.7 and 18 μm amorphous silicate features; the substructure is well matched by the presence of the olivine end-member forsterite (Mg2SiO4). Crystalline silicates are often observed as infrared emission features around the circumstellar disks of Herbig Ae/Be stars… Expand

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