A5110259789- Stellar, planetary, and galactic studies
- Photocathodes and Microchannel Plates
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Spacecraft Design and Technology
- Atmospheric Ozone and Climate
- Adaptive optics and wavefront sensing
- Spacecraft and Cryogenic Technologies
- Solar and Space Plasma Dynamics
- Calibration and Measurement Techniques
- Gamma-ray bursts and supernovae
- Optical Coatings and Gratings
- Planetary Science and Exploration
- Power Line Communications and Noise
- Spectroscopy and Laser Applications
- Head and Neck Cancer Studies
- CCD and CMOS Imaging Sensors
- Astronomical Observations and Instrumentation
- Dark Matter and Cosmic Phenomena
- Cancer Diagnosis and Treatment
- Astrophysics and Cosmic Phenomena
- PAPR reduction in OFDM
- Astrophysical Phenomena and Observations
- Space Satellite Systems and Control
Washington University in St. Louis
2024
Southwest Research Institute
2018-2023
At Bristol
2022
Stephen F. Austin State University
2019
Planetary Science Institute
2013-2017
University of Colorado System
2006-2013
University of Colorado Boulder
1999-2012
Laboratory for Atmospheric and Space Physics
2001-2012
Peter MacCallum Cancer Centre
2010
Arizona State University
2004
PUNCH is a Small Explorer constellation mission in development for NASA's Heliophysics Division. will image the transition zone between outer reaches of solar corona and wind inner heliosphere, helping to unify fields physics (space) physics. A four microsatellites (microsats) Sun-synchronous LEO produce deep field, continuous, 3D visible-light images young from 6R<inf>s</inf> 180R<inf>s</inf> polarized visible light. single Narrow Field Imager (NFI) on one microsat captures 6...
We present optical and near-infrared photometry spectroscopy of the type Ia SN 1998bu in Leo I Group galaxy M96 (NGC 3368). The data set consists 356 photometric measurements 29 spectra between UT 1998 May 11 July 15. well-sampled light curve indicates supernova reached maximum B on 19.3 (JD 2450952.8 +/- 0.8) with = 12.22 0.03 V 11.88 0.02. Application a revised version Multicolor Light Curve Shape (MLCS) method yields an extinction toward A_V 0.94 0.15 mag, was average luminosity compared...
Atmospheric escape is a fundamental process that affects the structure, composition, and evolution of many planets. The signatures are detectable on close-in, gaseous exoplanets orbiting bright stars, owing to high levels extreme-ultraviolet irradiation from their parent stars. Colorado Ultraviolet Transit Experiment (CUTE) CubeSat mission designed take advantage near-ultraviolet stellar brightness distribution conduct survey extended atmospheres nearby close-in CUTE payload magnifying NUV...
Abstract We present a first-principles analytic treatment of modern multivane occulters in circular (coronagraph) and linear (heliospheric imager) geometry, develop simplified theory that is useful for designing predicting their performance, explain certain visual artifacts, explore the performance limits occulters. Multivane are challenging to design part because they violate conditions both Fraunhofer Fresnel approximations diffraction theory, new designs have therefore generally required...
NASA’s suborbital program provides an opportunity to conduct unique science experiments above Earth’s atmosphere and is a pipeline for the technology personnel essential future space astrophysics, heliophysics, atmospheric missions. In this paper, we describe three astronomy payloads developed (or in development) by Ultraviolet Rocket Group at University of Colorado. These far-ultraviolet (UV) (100–160[Formula: see text]nm) spectrographic instruments are used study range scientific topics,...
The Colorado Ultraviolet Transit Experiment (CUTE) is a near-UV (2550 - 3300 Å) 6U cubesat mission designed to monitor transiting hot Jupiters quantify their atmospheric mass loss and magnetic fields. CUTE will probe both atomic (Mg Fe) molecular (OH) lines for evidence of enhanced transit absorption, search early ingress due bow shocks ahead the planet's orbital motion. As dedicated mission, observe ⪆ 60 spectroscopic transits over nominal seven month mission. This represents...
Abstract The Terminal Tracking Camera system (TTCam) on the NASA Lucy Trojan asteroid Discovery mission consists of a pair block redundant cameras and their associated electronics that are mounted spacecraft’s Instrument Pointing Platform co-boresighted with rest mission’s science payload instruments. primary function TTCams is as navigation designed to provide an autonomous onboard late pre-encounter update location each flyby target relative spacecraft. However, once terminal tracking...
PurposeAbout 40–60% of patients treated with post-operative radiotherapy for parotid cancer experience ipsilateral sensorineural hearing loss. Intensity-modulated (IMRT) can reduce radiation dose to the cochlea. COSTAR, a phase III trial, investigated role cochlear-sparing IMRT (CS-IMRT) in reducing loss.MethodsPatients (pT1-4 N0-3 M0) were randomly assigned (1:1) 3-dimensional conformal (3DCRT) or CS-IMRT by minimisation, balancing centre and 60Gy 65Gy 30 daily fractions. The primary...
We present new far-ultraviolet (far-UV) spectra of an oxygen-rich knot in the Large Magellanic Cloud supernova remnant N132D, obtained with Hubble Space Telescope (HST)-Cosmic Origins Spectrograph (COS). Moderate-resolution (Δv ≈ 200 km s−1) HST far-UV bandpass (1150 Å ≲ λ 1750 Å) show emission from several ionization states oxygen as well trace amounts other species. use improvements sensitivity and resolving power offered by COS to separate contributions different velocity components...
High resolution spectroscopy is the foundation for many of most challenging and productive all astronomical observations. A highly precise, repeatable stable wavelength calibration especially essential long term RV The two references in wide use visible wavelengths, iodine absorption cells thorium/argon lamps, each have fundamental limitations which restrict their ultimate utility. We are exploring possibility adapting emerging laser frequency comb technology development at National...
The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) is a far ultraviolet (FUV) rocket-borne experiment designed to study the atomic-to-molecular transitions within translucent interstellar clouds. CHESS an objective echelle spectrograph operating at f/12.4 and resolving power of 120,000 over band pass 100 – 160 nm. flight grating product research development project with LightSmyth Inc. was coated Goddard Space Flight Center (GSFC) Al+LiF. It has empirically-determined groove...
Approximately half of cancer-affected patients receive radiotherapy (RT).The doses delivered have been determined upon empirical experience based average radiation responses.Ideally higher curative might be employed in with genuinely normal responses and importantly hypersensitive would spared the consequences excessive tissue damage if they were indentified before treatment.Rad21 is an integral subunit cohesin complex, which regulates chromosome segregation DNA eukaryotes.We show here, by...
A key astrophysical theme that will drive future UV/optical space missions is the life cycle of cosmic matter, from flow intergalactic gas into galaxies to formation and evolution exoplanetary systems. Spectroscopic systems capable delivering high resolution with low backgrounds be essential addressing these topics. Towards this end, we are developing a rocket-borne instrument serve as pathfinder for high-sensitivity, highresolution UV spectrographs. The Colorado High-resolution Echelle...
Roughly 40 billion M dwarfs in our galaxy host at least one small planet the habitable zone (HZ). The stellar ultraviolet (UV) radiation from is strong and highly variable, impacts planetary atmospheric loss, composition habitability. These effects are amplified by extreme proximity of their HZs (0.1–0.4 AU). Knowing UV environments dwarf planets will be crucial to understanding a key parameter discriminating between biological abiotic sources for observed biosignatures. Star-Planet Activity...
There is unique and groundbreaking science to be done with a new generation of UV spectrographs that cover wavelengths in the "Lyman Ultraviolet" (LUV; 912 - 1216 Ang). no astrophysical basis for truncating spectroscopic wavelength coverage anywhere between atmospheric cutoff (3100 Ang) Lyman limit (912 Ang); usual reasons this happens are all technical. The available LUV includes critical problems astrophysics ranging from habitability exoplanets reionization IGM. Crucially, local Universe...
We present the first science results from Sub-orbital Local Interstellar Cloud Experiment (SLICE): moderate resolution 1020–1070 Å spectroscopy of four sightlines through local interstellar medium. High signal-to-noise (S/N) spectra η Uma, α Vir, δ Sco, and ζ Oph were obtained during a 2013 April 21 rocket flight. The SLICE observations constrain density, molecular photoexcitation rates, physical conditions in material toward Sco Oph. Our indicate factor two lower total N(H2) than previously...
We present the Colorado High-resolution Echelle Stellar Spectrograph (CHESS) sounding rocket payload. The design uses a mechanical collimator made from grid of square tubing, an objective echelle grating, holographically-ruled cross-disperser, new 40 mm MCP with cross strip anode or delta-doped 3.5k x CCD detector. optics are suspended using carbon fiber rods epoxied to titanium inserts create space frame structure. A preliminary is presented.
We present the flight performance and preliminary science results from first of Sub-orbital Local Interstellar Cloud Experiment (SLICE). SLICE is a rocket-borne far-ultraviolet instrument designed to study diffuse interstellar medium. The payload comprises Cassegrain telescope with LiF-coated aluminum optics feeding Rowland Circle spectrograph operating at medium resolution (R ~ 5000) over 102 – 107 nm bandpass. novel method for cleaning LiF-overcoated Al instrumental wavelength calibration,...
We present an imaging spectrometer developed for narrowband at 1035 A with high (approximately 1-arc sec) spatial resolution over a modest field of view 5 arc min). The instrument is based on conventional Gregorian telescope aberration-corrected holographic rulings the secondary optic. These aberration-correcting enable stigmatic in diffracted light minimum number optical elements, thereby maintaining system efficiency. capabilities this allow us to map distribution UV-emitting material hot...
The Star-Planet Activity Research CubeSat (SPARCS) is a NASA-funded astrophysics mission, devoted to the study of ultraviolet (UV) time-domain behavior in low-mass stars. Given their abundance and size, stars are important targets search for habitable-zone, exoplanets. However, not enough known about flare quiescent emission, which powers photochemical reactions on atmospheres possible planets. Over its initial 1-year SPARCS will stare at ~10 order measure short- (minutes) long- (months)...
We discuss the design of a new high-efficiency, high-resolution far ultraviolet echelle spectrograph. Our project concentrates on utilizing technologies for gratings and detectors to reduce impact scattered light maximize quantum efficiency over large bandpass. This program will enable advances in vast number astrophysical subjects. Topics ranging from protoplanetary disks intergalactic medium can be addressed by incorporating such spectrograph into future, long-duration mission.
We have worked to define the compelling next generation General Astrophysics science that 4m implementation of HabEx mission concept might enable. These drivers been used requirements for a far ultraviolet (FUV) spectrograph design telescope meets needs these programs. describe both and baseline instrument, modes it support, choices were made optimize performance. The operational performance instrument in cooperation with rest is also discussed.