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We present the flight performance and preliminary science results from the first flight of the Sub-orbital Local Interstellar Cloud Experiment (SLICE). SLICE is a rocket-borne far-ultraviolet instrument designed to study the diffuse interstellar medium. The SLICE payload comprises a Cassegrain telescope with LiF-coated aluminum optics feeding a Rowland Circle spectrograph operating at medium resolution (R ~ 5000) over the 102 – 107 nm bandpass. We present a novel method for cleaning LiF-overcoated Al optics and the instrumental wavelength calibration, while the details of the instrument design and assembly are presented in a companion proceeding (Kane et al. 2013). We focus primarily on first results from the spring 2013 launch of SLICE in this work. SLICE was launched aboard a Terrier-Black Brant IX sounding rocket from White Sands Missile Range to observe four hot stars sampling different interstellar sightlines. The instrument acquired approximately 240 seconds of on-target time for the science spectra. We observe atomic and molecular transitions (HI, OI, CII, OVI, H2) tracing a range of temperatures, ionization states, and molecular fractions in diffuse interstellar clouds. Initial spectral synthesis results and future plans are discussed.

We present a conceptual design for a high-resolution optical spectrograph appropriate for mounting at Cassegrain on a large aperture telescope. The design is based on our work for the Gemini High Resolution Optical Spectrograph (CUGHOS) project. Our design places the spectrograph at Cassegrain focus to maximize throughput and blue wavelength coverage, delivering R=40,000 resolving power over a continuous 320–1050 nm waveband with throughputs twice those of current instruments. The optical design uses a two-arm, cross-dispersed echelle format with each arm optimized to maximize efficiency. A fixed image slicer is used to minimize optics sizes. The principal challenge for the instrument design is to minimize flexure and degradation of the optical image. To ensure image stability, our opto-mechanical design combines a cost-effective, passively stable bench employing a honeycomb aluminum structure with active flexure control. The active flexure compensation consists of hexapod mounts for each focal plane with full 6-axis range of motion capability to correct for focus and beam displacement. We verified instrument performance using an integrated model that couples the optical and mechanical design to image performance. The full end-to-end modeling of the system under gravitational, thermal, and vibrational perturbations shows that deflections of the optical beam at the focal plane are

A key astrophysical theme that will drive future UV/optical space missions is the life cycle of cosmic matter, from the flow of intergalactic gas into galaxies to the formation and evolution of exoplanetary systems. Spectroscopic systems capable of delivering high resolution with low backgrounds will be essential to addressing these topics. Towards this end, we are developing a rocket-borne instrument that will serve as a pathfinder for future high-sensitivity, highresolution UV spectrographs. The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) will provide 2 km s-1 velocity resolution (R = 150,000) over the 100 - 160 nm bandpass that includes key atomic and molecular spectral diagnostics for the intergalactic medium (H I Lyman-series, O VI, N V, and C IV), exoplanetary atmospheres (H I Lyman-alpha, O I, and C II), and protoplanetary disks (H2 and CO electronic band systems). CHESS uses a novel mechanical collimator comprised of an array of 10 mm x 10 mm stainless steel tubes to feed a low-scatter, 69 grooves mm-1 echelle grating. The cross-disperser is a holographically ruled toroid, with 351 grooves mm-1. The spectral orders can be recorded with either a 40 mm cross-strip microchannel plate detector or a 3.5k x 3.5k δ-doped CCD. The microchannel plate will deliver 30 μm spatial resolution and employs new 64 amp/axis electronics to accommodate high count rate observations of local OB stars. CHESS is scheduled to be launched aboard a NASA Terrier/Black Brant IX sounding rocket from White Sands Missile Range in the summer of 2013.

We have assembled and launched the Diffuse Interstella r Cloud Experiment (DICE), an instrument capable of recording high resolution ( / = 30,000) spectra in the Far Ultraviolet (F UV). Absorption measurements toward nearby bright stars can provide new in sight into the processes governing warm-hot gas in the Local Interstella r Medium. It flew on May 21 st , 2010. An anomaly in the Black Brant motor subjected the payload to abnormally high vibration. As a result, the optics were misaligned and no sp ectral data fell on the detector. Here we present the details of mechanical and electrical integration with NASA launch systems, as well as optical alignment of the telescope and spectrograph. In addition, we summarize the flight results. Keywords: Far Ultraviolet Spectroscopy, Local Bubble, Sounding Rocket 1. SCIENTIFIC MOTIVATION The current model of the Local Inters tellar Medium (LISM) contains 3 phases of gas: cold (T ~ 100 K, n ~ 100 cm -3 ), warm (T~10 4 to 10 5

The Cosmic Origins Spectrograph (COS) was installed into the Hubble Space Telescope (HST) during Servicing Mission 4 (SM4) in May 2009. COS is designed to obtain spectra of faint objects at moderate spectral resolution (R > 16,000) in two channels: FUV, covering wavelengths from 1150 to 1450 A; and NUV, covering 1700 - 3200 A. Two low resolution gratings (R > 1500) cover the < 900 - 2050 A (FUV) and 1650 - 3200 A (NUV) wavelength regions. An imaging capability is also available on the NUV channel. As part of the Hubble Servicing Mission Observatory Verification (SMOV) program, an extensive period of checkout, fine-tuning and preliminary characterization began after the installation of COS. The COS SMOV program was a cooperative effort between the Space Telescope Science Institute and the Instrument Definition Team based at the University of Colorado. Nearly 2800 COS exposures in 34 separate observing programs were obtained during the course of SMOV. Early activities included an initial instrument functional checkout, turn-on and initial characterization of the detectors, NUV and FUV channel focus and alignment, and target acquisition verification and assessment. Once this initial period was completed, science-related calibrations and verifications were performed in order to prepare the instrument for normal science operations. These activities included wavelength calibration, flux calibration, detector flat field characterization, spectroscopic performance verification, high S/N operation, and thermal and structural stability measurements. We discuss the design, execution and results of the SMOV program, including the interrelationships between the various tasks, and how the pre-launch plan was adjusted in real-time due to changing conditions.

We describe a vacuum collimator that we have assembled to characterize the windowless ultraviolet properties of a sounding rocket spectrographic telescope. The collimator comprises a Cassegrain telescope, with SiC coated optics, used in the pre-flight calibration phase of the Far Ultraviolet Spectroscopic Explorer, and vacuum skins provided by NASA/Wallops. The collimator focal plane has a three-axis motorized stage, which we have used for the precision placement of a knife edge focal locator along with pinhole and flat-field sources. We describe the focusing procedure and present the results of a number of experiments whereby the collimator, telescope and spectrograph point spread functions were determined and a spectro-spatial flat-field of the detector was acquired.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We present the design of a pinhole lamp recently flown aboard two NASA/JHU sounding rocket missions as a wavelength standard for a far-UV spectrograph with a 900 - 1400 Angstrom bandpass. Lamp configuration, spectral output, gas supplies, payload accommodation and operation procedures are discussed. This lamp could easily be incorporated into future far-UV spectroscopic orbital missions and would benefit science return. We also discuss the use of Bayard-Alpert tubes (ionization gauges) as far-UV sources, which have the advantage of not requiring an external gas supply. At pressures between 10-5 and 10-7 Torr these tubes produce a strong emission line spectra, caused by electron impact with residual gas atoms in the vacuum. Below 10-7 Torr the residual gas line intensities have weaken enough to reveal the long wavelength tail of a 150 eV bremsstrahlung spectrum produced by electron impact onto tungsten grid. The use of ionization gauges in flat field and end-to-end calibration experiments is described. We show how an ionization gauge and spectrograph can be used as a real- time residual gas analyzer sensitive to atomic and molecular gas species that emit within the bandpass. Such a device could be useful in material processing and contamination control environments.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.