Search Publications

Search for Interstellar Water in the Translucent Molecular Cloud toward HD 154368

Stauffer, John; Neufeld, David; Melnick, Gary J. +2 more

We report an upper limit of 9 × 10¹² cm^-2 on the column density of water in the translucent cloud along the line of sight toward HD 154368. This result is based on a search for the C-X band of water near 1240 Å carried out using the Goddard High-Resolution Spectrograph (GHRS) of the Hubble Space Telescope. Our observational l…

WFPC2 Observations of NGC 454: An Interacting Pair of Galaxies

Panagia, N.; Stiavelli, M.; Romaniello, M. +3 more

We present Wide Field Planetary Camera 2 images in the F450W, F606W, and F814W filters of the interacting pair of galaxies NGC 454. Our data indicate that the system is in the early stages of interaction. A population of young star clusters has formed around the late component, and substantial amounts of gas have sunk into the center of the earlie…

A Fit to the Simultaneous Broadband Spectrum of Cygnus X-1 Using the Transition Disk Model

Misra, R.; Melia, Fulvio; Chitnis, V. R.

We have used the transition disk model to fit the simultaneous broadband (2-500 keV) spectrum of Cygnus X-1 from OSSE and Ginga observations. In this model, the spectrum is produced by saturated Comptonization within the inner region of the accretion disk, where the temperature varies rapidly with radius. In an earlier attempt, we demonstrated the…

Kinematics of the narrow-line region of NGC 1068

Dietrich, M.; Wagner, S. J.

We investigated the kinematics of the Narrow Line Region of NGC 1068. In order to study the kinematics and to determine whether the unusual broad line width can be attributed to motion of NLR clouds in a deep gravitational potential or to expanding shocks, we carried out spatially resolved echelle spectroscopy. High spectral resolution enables the…

Dust in LBV Nebulae

Waters, L. B. F. M.; Morris, P. W.; Lamers, H. J. G. L. M. +2 more

Hubble Space Telescope Astrometric Observations and Orbital Mean Motion Corrections for the Inner Uranian Satellites

Pascu, Dan; Rohde, James R.; Seidelmann, P. Kenneth +6 more

The 10 small inner satellites of Uranus were discovered in 1986 with Voyager 2 and not seen again until 1994, when eight were recovered with the Hubble Space Telescope Wide Field Planetary Camera 2 for astrometric, dynamical, and photometric studies. Thirty-three exposures were taken on 1994 August 14 with the PC1 chip in the BVRI filters. Measura…

Limits on the Boron Isotopic Ratio in HD 76932

Rebull, Luisa; Duncan, Douglas; Johansson, Sveneric +2 more

Data in the λ2090 B region of HD 76932 have been obtained at a high signal-to-noise ratio using the Hubble Space Telescope Goddard High-Resolution Spectrograph echelle at a resolution of 90,000. This wavelength region has been previously identified as a likely candidate for observing the ¹¹B/¹⁰B isotopic splitting. The observ…

NGC 5252 - a Liner undercover

Goncalves, A. C.; Veron, P.; Veron-Cetty, M. -P.

Ground based long slit spectroscopic observations of the nuclear region of NGC 5252, and Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra of the nucleus and two bright knots located 0.36'' NE and 0.31'' SW from it, show that the nuclear region exhibits the characteristics of a Liner with exceptionally strong [O i] emission, all…

Far-Ultraviolet and Visible Imaging of the Nucleus of M32

Casertano, Stefano; Cole, Andrew A.; Ballester, Gilda E. +15 more

We have imaged the nucleus of M32 at 1600 Å (FUV) and 5500 Å (V) using the Wide-Field/Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope. We detected the nucleus at 1600 Å using the redleak-free Woods filter on WFPC2. The far-ultraviolet (FUV) light profile can be fitted with a Gaussian of FWHM 0.46" (4.6 pixels) but cannot be resolved i…

Infrared Observations of the Transition from Chaotic to Crystalline Silicates via Thermal Annealing in the Laboratory

Hallenbeck, S.; Nuth, J.