Search Publications
Infrared Space Observatory-Long Wavelength Spectrometer Detection of the 112 Micron HD J = 1 --> 0 Line toward the Orion Bar
van Dishoeck, Ewine F.; Wright, Christopher M.; Kessler, Martin F. +2 more
We report the first detection outside of the solar system of the lowest pure rotational J=1-->0 transition of the HD molecule at 112 µm. The detection was made toward the Orion Bar using the Fabry-Pérot interferometer of the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory. The line appears in emission with an in…
Phase-resolved Far-Ultraviolet Hubble Space Telescope Spectroscopy of the Peculiar Magnetic White Dwarf RE J0317-853
Jordan, S.; Burleigh, M. R.; Schweizer, W.
We present phase-resolved, far-UV Hubble Space Telescope Faint Object Spectrograph spectra of the rapidly rotating, highly magnetic white dwarf RE J0317-853. Using these data, we construct a new model for the magnetic field morphology across the stellar surface. From an expansion into spherical harmonics, we find that the range of magnetic field s…
Emission-Line Galaxies from the NICMOS/Hubble Space Telescope Grism Parallel Survey
Gardner, Jonathan P.; Teplitz, Harry I.; Williams, Robert E. +10 more
We present the first results of a survey of random fields with the slitless G141 (λc=1.5 µm, Δλ=0.8 µm) grism on the near-IR camera and multiobject spectrometer (NICMOS) on board the Hubble Space Telescope (HST). Approximately 64 arcmin2 have been observed at intermediate and high Galactic latitudes. The 3 σ limit…
A Study of Lyα Quasar Absorbers in the Nearby Universe
Impey, C. D.; Petry, C. E.; Flint, K. P.
Spectroscopy of 10 quasars obtained with the Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) is presented. In the 10 sight lines, we detect 357 absorption lines above a significance level of 3 σ and 272 lines above a significance level of 4.5 σ. Automated software is used to detect and identify the lines, almost all…
The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XIV. The Cepheids in NGC 1365
Illingworth, Garth D.; Madore, Barry F.; Freedman, Wendy L. +21 more
We report the detection of Cepheid variable stars in the barred spiral galaxy NGC 1365, located in the Fornax cluster, using the Hubble Space Telescope (HST) Wide Field and Planetary Camera 2 (WFPC2). Twelve V (F555W) and four I (F814W) epochs of observation were obtained. The two photometry packages ALLFRAME and DoPHOT were separately used to obt…
Physical Conditions in the Emission-Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395
Filippenko, Alexei V.; Ho, Luis C.; Shields, Joseph C. +2 more
We have combined Hubble Space Telescope/Faint Object Spectrograph, ground-based, and Infrared Space Observatory spectra of the nucleus of NGC 4395, the least luminous and nearest known type 1 Seyfert galaxy. The spectra show emission lines from a wide range of ionization states and critical densities. We have generated multicomponent photoionizati…
An Edge-brightened Bicone in the Nuclear Regions of Cygnus A
Tadhunter, C. N.; Packham, C.; Sparks, W. +5 more
Infrared-imaging observations that span the wavelength range of 0.8-2.35 µm have been obtained for the archetypal powerful radio galaxy Cygnus A using the Near-Infrared Camera and Multiobject Spectrograph on board the Hubble Space Telescope. At 2.25 µm, the images are dominated by the presence of a nuclear point source (FWHM < 0.21"…
HUBBLE SPACE TELESCOPE Observations of the Local Group Dwarf Galaxy Leo I
Freedman, Wendy L.; Mateo, Mario; Stetson, Peter B. +10 more
We present deep HST F555W (V) and F814W (I) observations of a central field in the Local Group dwarf spheroidal (dSph) galaxy Leo I. The resulting color-magnitude diagram (CMD) reaches I~=26 and reveals the oldest ~=10-15 Gyr old turnoffs. Nevertheless, a horizontal branch is not obvious in the CMD. Given the low metallicity of the galaxy, this li…
Injection of>~10 MeV Protons in Association with a Coronal Moreton Wave
Torsti, Jarmo; Teittinen, Matti; Thompson, Barbara J. +1 more
We report extreme-UV observations of the coronal Moreton wave and concurrent observations of ~10-100 MeV protons. Observations are carried out with the Extreme-UV Imaging Telescope and the Energetic and Relativistic Nuclei and Electron instrument on board the SOHO spacecraft. We study the proton events associated with coronal mass ejections (CMEs)…
Nonlinear Sunspot Transition Region Oscillations in NOAA 8378
Wilhelm, K.; Kjeldseth-Moe, O.; Brynildsen, N. +1 more
Observations obtained with the Solar and Heliospheric Observatory joint observing program for velocity fields in sunspot regions are used to study the 3 minute transition region oscillations above four sunspots. Here we report mainly on the results obtained for NOAA 8378, based on simultaneous recordings of the transition region lines O V λ629 and…