Mid-Infrared Spectroscopy with SOFIA, EXES, and TEXES

We are building two high resolution, mid-infrared spectrographs; the Texas Echelon-cross-Echelle Spectrograph (TEXES) is designed for ground-based telescopes and the Echelon-cross-Echelle Spectrograph (EXES) is designed for the Stratospheric Observatory for Infrared Astronomy (SOFIA). Both spectrographs operate at 4-28 @x μ m in three spectroscopic modes: a cross-dispersed mode with R ~ 10⁵, and longslit modes with either R ~ 2 × 10⁴ or R ~ 4000. Both instruments use an echelon, a coarsely ruled, steeply blazed diffraction grating, to achieve high resolution. These instruments will be well suited for the study of molecular lines in the cold interstellar medium, around young stars, and in planets.