Search Publications
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…
Optical and ultraviolet observations of a strong flare in the young, single K2 dwarf LQ Hya
Montes, D.; Collier Cameron, A.; Saar, S. H. +1 more
We present high-resolution optical echelle spectra and IUE observations during a strong flare on 1993 December 22 in the very active, young, rapidly rotating, single K2 dwarf LQ Hya. The initial impulsive phase of the flare, which started sometime between 2:42 ut and 4:07 ut, was characterized by strong optical continuum enhancement and blueshifte…
Near-infrared photometry of isolated spirals with and without an AGN. I. The data
Roth, M.; Durret, F.; González Delgado, R. M. +6 more
We present infrared imaging data in the J and K' bands obtained for 18 active spiral galaxies, together with 11 non active galaxies taken as a control sample. All of them were chosen to satisfy well defined isolation criteria so that the observed properties are not related to gravitational interaction. For each object we give: the image in the K' …
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…
Simulations of small-scale explosive events on the Sun
Innes, D. E.; Tóth, G.
Small-scale explosive events or microflares occur throughout the chromospheric network of the Sun. They are seen as sudden bursts of highly Doppler-shifted spectral lines of ions formed at temperatures in the range 2×104−5×105 K. They tend to occur near regions of cancelling photospheric magnetic fields and are thought to be directly associated wi…
A ring galaxy at z=1 lensed by the cluster Abell 370
Altieri, B.; Metcalfe, L.; Kneib, J. P. +3 more
We present a study of a very peculiar object found in the field of the cluster-lens Abell 370. This object displays, in HST imaging, a spectacular morphology comparable to nearby ring-galaxies. From spectroscopic observations at the CFHT, we measured a redshift of z=1.062 based on the identification of [Oii] 3727 Angstroms and [Nev] 3426 Angstroms…
Similarities between in situ measurements of local dust light scattering and dust flux impact data within the coma of 1P/Halley
Fulle, M.; Levasseur-Regourd, A. C.; McBride, N. +1 more
In situ measurements of the light locally scattered by cometary dust, as well as the local dust spatial density are only available for one comet, 1P/Halley. These data, returned from the Optical Probe Experiment (OPE) and the Dust Impact Detection System (DIDSY) aboard the European Space Agency spacecraft Giotto, are re-assessed in light of the re…
Stellar Encounters with the Oort Cloud Based on HIPPARCOS Data
Latham, David W.; García-Sánchez, Joan; Preston, Robert A. +4 more
We have combined Hipparcos proper-motion and parallax data for nearby stars with ground-based radial velocity measurements to find stars that may have passed (or will pass) close enough to the Sun to perturb the Oort cloud. Close stellar encounters could deflect large numbers of comets into the inner solar system, which would increase the impact h…