A5071129810- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Spacecraft and Cryogenic Technologies
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Space Exploration and Technology
- Atmospheric Ozone and Climate
- Pulsars and Gravitational Waves Research
- Nuclear Physics and Applications
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- Adaptive optics and wavefront sensing
- Particle Accelerators and Free-Electron Lasers
- Spectroscopy and Laser Applications
- Atomic and Molecular Physics
- Photonic and Optical Devices
- Radio Astronomy Observations and Technology
- Ionosphere and magnetosphere dynamics
University of Minnesota
2015-2024
Twin Cities Orthopedics
2018-2024
Old Dominion University
2024
University of Minnesota System
2001-2020
Joint Institute for Nuclear Astrophysics
2018
University of California, Berkeley
2018
The Ohio State University
2016
University of Notre Dame
2016
Ames Research Center
2005-2015
Max Planck Institute for Astronomy
2014
We report 4.5 micron luminosities for 27 nearby (D < 5 Mpc) dwarf irregular galaxies measured with the Spitzer Infrared Array Camera. have constructed luminosity-metallicity (L-Z) relation 25 secure distance and interstellar medium oxygen abundance measurements. The L-Z is 12+log(O/H) = (5.78 +/- 0.21) + (-0.122 0.012) M_[4.5], where M_[4.5] absolute magnitude at micron. dispersion in near-infrared smaller than corresponding optical relation. subsequently derived stellar mass-metallicity...
We present 7.5-13.4 μm infrared (IR) spectrophotometry (R≃180-360) of the 10 silicate emission from dust in inner coma (i.e., within a diameter 3'') comet C/1995 O1 (Hale-Bopp) at four temporal epochs 1996 October through 1997 June during Hale-Bopp's approach to, arrival at, and recession perihelion. feature is strongest observed any to date: flux-to-continuum ratio 10.0 2.5 2.8 AU preperihelion, increases 3.0 0.93 AU, then decreases 2.4 1.7 postperihelion, dropping more rapidly strength...
Infrared imaging and spectroscopic studies suggest that regions of recent massive star formation exist in the center region Galaxy. Here, we present J(1.29 microns), H(1.67 K(2.23 L'(3.82 microns) broadband images, as well Br gamma alpha hydrogen recombination line images Object #17 detected a near-infrared survey at projected distance 30 pc from Galactic center. Our data show this source is cluster luminous stars with emission lines. The flux width these are similar to those Of-type stars,...
Gemini-N observed the properties of dust ejected from nucleus comet 9P/Tempel 1 before and after its encounter with Deep Impact. Marked changes were seen in 7.8- to 13-micrometer spectral energy distribution derived grain inner coma. A strong, broad silicate feature dominated by emission amorphous pyroxene, olivine, magnesium-rich crystalline olivine had developed hour impact. The mass is ≅10 4 10 6 kilograms on basis our models. Twenty-six hours later faded, leaving a smooth featureless...
The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides unparalleled opportunity to investigate the previously poorly sampled evolution of novae in regime. This paper presents observations 52 Galactic/Magellanic Cloud We included X-Ray Telescope (0.3–10 keV) instrument count rates UltraViolet Optical (1700–8000 Å) filter photometry. Also analysis are publicly available pointed 10 additional archives....
Abstract Salmon calcitonin (synthetic) was iodinated with the chloramine-T method and purified by gel filtration. The product virtually free of uniodinated molecules as determined enzymatic digestion amino acid analysis. Greater than 80% incorporated iodine in form monoiodotyrosine. hormone bound specifically to renal skeletal receptors indistinguishable from species bioassays based on either or action calcitonin. degradation salmon 125I-calcitonin plasma membranes inhibited agents that did...
We present the first spectroscopic measurements of [OIII] 5007 A line in two z ~ 3.1 Lyman-alpha emitting galaxies (LAEs) using new near-infrared instrument LUCIFER1 on 8.4m Large Binocular Telescope (LBT). also describe optical imaging and observations used to identify these Lya galaxies. Using we have measured accurate systemic redshifts for galaxies, discovered a velocity offset between Ly-alpha lines both, with peaking 342 125 km/s redward velocity. These offsets imply that there are...
Rectified diameters and albedo estimates of 1517 main-belt asteroids selected from IRAS the Mid-Course Space Experiment asteroid photometry catalogs are derived updated infrared thermal models, Standard Thermal Model Near-Earth Asteroid (NEATM), Monte Carlo simulations, using new Minor Planet Center compilations absolute magnitudes (H values) constrained by occultation- radar-derived parameters. The NEATM approach produces a more robust estimate albedos diameters, yielding pv (NEATM mean)...
As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition L to T, which encompasses dissipation of cloud opacity appearance strong methane absorption. While there are hundreds known T-type dwarfs, first generation directly-imaged exoplanets were all L-type. Recently, Kuzuhara et al. (2013) announced discovery GJ 504 b, T dwarf exoplanet. b provides unique opportunity study atmosphere new exoplanet with ~500 K...
We are developing a stable and precise spectrograph for the Large Binocular Telescope (LBT) named "iLocater." The instrument comprises three principal components: cross-dispersed echelle that operates in YJ-bands (0.97-1.30 microns), fiber-injection acquisition camera system, wavelength calibration unit. iLocater will deliver high spectral resolution (R~150,000-240,000) measurements permit novel studies of stellar substellar objects solar neighborhood including extrasolar planets. Unlike...
Abstract We report on studies of classical nova (CN) explosions where we follow the evolution thermonuclear runaways (TNRs) oxygen–neon (ONe) white dwarfs (WDs). Using NOVA, a 1D hydrodynamic computer code, accrete solar matter until TNR is ongoing and then switch to mixed composition. This approach guided by results multidimensional TNRs in WDs, which find that sufficient mixing with WD core material occurs after well underway, levels enrichment CNONeMg elements are reached agree...
We present the analysis of 7.6-13.2 μm infrared (IR) spectrophotometry (R ≃ 250) comet C/1995 O1 (Hale-Bopp), in conjunction with concurrent observations that extend wavelength coverage spectral energy distribution from near- to far-infrared wavelengths. The include temporal epochs preperihelion (1996 October and 1997 February UT), near perihelion (1997 April postperihelion June UT). Through modeling thermal emission small, amorphous carbon grains crystalline silicate Hale-Bopp's coma, we...
A medium-resolution 1.0-2.5 μm spectrum of the brown dwarf Gliese 229B has been obtained using facility spectrometer CGS4 on United Kingdom Infrared Telescope. In addition to broad spectral structure seen in earlier low-resolution observations, new reveals a large number absorption lines, many which can be identified with water vapor. Water and methane are both shown strong absorbers near-infrared object. Several features Gl that attributable match ones reflection giant outer planets and,...
We present 3.6, 4.5, 5.8, 8.0, 24, and 70 μm images of the Crab Nebula obtained with Spitzer Space Telescope IRAC MIPS cameras, low- high-resolution IRS spectra selected positions within nebula, a near-infrared ground-based image made in light [Fe II] 1.644 μm. The 8.0 image, bandpass that includes [Ar 7.0 μm, resembles general morphology visible Hα near-IR line emission, while 3.6 4.5 are dominated by continuum synchrotron emission. 24 show enhanced emission may be due to or presence small...
Mid-infrared observations of the Andromeda galaxy, M31, obtained with Infrared Array Camera on board Spitzer Space Telescope, are presented. The image mosaics cover areas approximate 3.7deg x 1.6deg and include satellite galaxies M32 NGC 205. appearance M31 varies dramatically in different mid-infrared bands, from smooth bulge disk old stellar population seen at 3.6um to well-known '10 kpc ring' dominating 8um image. similarity optical isophotes nearly constant optical-mid-infrared color...
view Abstract Citations (110) References (30) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS AFGL 2004: an Infrared Quintuplet near the Galactic Center Nagata, Tetsuya ; Woodward, Charles E. Shure, Mark Pipher, Judith L. Okuda, Haruyuki Near-IR broad-band images at K, L-prime, and M-prime, maps L, N, are presented for a peculiar IR quintuplet source along line of sight toward center Radio Arc. The five members have very red energy distribution. Most likely...
We present spectral energy distribution modelling of 6875 stars in omega Centauri, obtaining stellar luminosities and temperatures by fitting literature photometry to state-of-the-art MARCS models. By comparison four different sets isochrones, we provide a new distance estimate the cluster 4850 +/- 200 (random) 120 (systematic error) pc, reddening E(B-V) = 0.08 0.02 mag differential Delta[E(B-V)] < for an age 12 Gyr. Several post-early-AGB candidates are also found. Infra-red excesses...
Aims.We investigate the energy sources of infrared (IR) emission and their relation to radio continuum at various spatial scales within Scd galaxy M 33.
Progress in the development of high-speed electrooptic A/D converters is reviewed. this type have been operated at 1 gigasample/second (GS/s) 2- and 4-bit structures for 500-MHz analog bandwidth. The converter consists an array LiNbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> guided-wave interferometric modulators that function as amplitude analyzer, pulsed lasers optical sampling, monolithic comparators/demultiplexers to generate...
We have performed H and KS band observations of the planetary system around HR 8799 using new AO at Large Binocular Telescope PISCES Camera. The excellent instrument performance (Strehl ratios up to 80% in band) enabled detection innermost planet, 8799e, for first time. magnitudes 8799e are similar those planets c d, with planet e being slightly brighter. Therefore, is likely more massive than d. also explored possible orbital configurations their stability. confirm that orbits b, consistent...
We have performed H and Ks band observations of the planetary system around HR 8799 using new AO at Large Binocular Telescope PISCES Camera. The excellent instrument performance (Strehl ratios up to 80% in band) enabled detection inner planet HR8799e for first time. magnitudes are similar those planets c d, with e slightly brighter. Therefore, is likely more massive than d. also explored possible orbital configurations their stability. confirm that orbits b, consistent being circular...
Context. Astrometric monitoring of directly-imaged exoplanets allows the study their orbital parameters and system architectures. Because most planets have long periods (>20 AU), accurate astrometry is challenging when based on data acquired timescales a few years usually with different instruments. The LMIRCam camera LBT being used for LEECH survey to search characterize young adolescent in L' band, including Aims. We first aim provide good astrometric calibration LMIRCam. Then, we...