title: The Diffuse Interstellar Cloud Experiment: a high-resolution far-ultraviolet spectrograph.
abstract: We have designed, assembled, and launched a sounding rocket payload to perform high-resolution far-ultraviolet spectroscopy. The instrument is functionally a Cassegrain telescope followed by a modified Rowland spectrograph. The spectrograph was designed to achieve a resolving power (R=λ/δλ) of 60,000 in a compact package by adding a magnifying secondary optic. This is enabled by using a holographically ruled grating to minimize aberrations induced by the second optic. We designed the instrument to observe two stars on opposing sides of a nearby hot/cold gas interface. Obtaining spectra of the O VI doublet in absorption toward these stars can provide new insight into the processes governing hot gas in the local interstellar medium. Here we present the optical design and alignment of the telescope and spectrograph, as well as flight results.
authors.affiliation: Center for Astrophysics and Space Astronomy, University of Colorado, 2000 Colorado Avenue, Duane Physics Building C333, Boulder, Colorado 80309, USA. eric.schindhelm@colorado.edu
authors.forename: Eric
authors.initials: E
authors.lastname: Schindhelm
authors.forename: Matthew
authors.initials: M
authors.lastname: Beasley
authors.forename: Eric B
authors.initials: EB
authors.lastname: Burgh
authors.forename: James C
authors.initials: JC
authors.lastname: Green