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Diffusive Shock Acceleration and the November 1991 Event Particle Diffusion Mean Free Paths as Observed from 'ULYSSES'

Keppler, E.; Quenby, J. J.; Drolias, B. +2 more

Hubble Space Telescope Observations of the Galactic Center Region at 1.02 Microns

Becklin, E. E.; Liu, T.; Henry, J. P. +1 more

We present HST observations of the galactic center region using the Planetary Camera with the F1042M filter at an effective wavelength of 1.02 micron. We detect several infrared sources seen at this wavelength before but with angular resolution better than previous observations. Our data reveal the source GZ A which was first seen by Rosa et al. (…

Heavy mass loss from the symbiotic star AS 304.

Munari, Ulisse; Buson, Lucio M.

IUE, optical and infrared observations of the previously poorly studied symbiotic star AS 304 are discussed. The IUE low-resolution spectra are dominated by very strong P Cygni profiles of the resonant lines of N v, Si IV and C IV, indicating that the hot component of AS 304 is losing mass at a high rate via a fast wind. These P Cygni profiles mak…

Composition of Interplanetary Ions in Recurrent Events: Measurements by HI-SCALE on Ulysses at 3-5 A.U.

Tappin, S. J.; Lanzerotti, L. J.; Gold, R. E. +2 more

CPC2: The Second Cape Photographic Catalogue. I - History, observations and plate measurements

Zacharias, N.; Murray, C. A.; de Vegt, C. +3 more

The Second Cape Photographic Catalog is discussed. The observations and measurements involved in the preparation of the first version of the catalog are described. The present stellar reference frame is reviewed, and the observational program, reduction process, and plate measurement for the catalog are examined.

Hubble Space Telescope Spectra of the Phase-modulated Wind in the SMC O+WR Binary R31

Bianchi, L.; Hutchings, J. B.; Morris, S. C.

We present HST/GHRS profiles of C IV 1500 A at conjunction phases 0.21, 0.26, and 0.72 of the 6.5 day O6+WN3 binary R31 in the SMC. We also use IUE archival data covering other orbital phases, There are strong changes in the line profile, depending on the line of view through an ionization bubble near the WR star. We fit a model for the stellar wi…

Measurement of direct current electric fields and plasma flow speeds in Jupiter's magnetosphere

Balogh, A.; Goetz, K.; Forsyth, R. J. +3 more

During the encounter of Ulysses with Jupiter, we have measured two components of the dc electric field and deduced from them the flow speed in the Io torus, as well as the presence of a polar cap region and what we interpret as a cleft region. Within the torus the flow speed is approximately equal to the speed of a plasma corotating with Jupiter b…

The polar heliospheric magnetic field

Suess, S. T.; Nerney, Steven

We describe the large-scale magnetic field morphology in the heliosheath. A simple argument, which depends only on the interstellar wind flowing nearly in the solar equatorial plane, shows that polar heliospheric magnetic fieldlines never approach the heliopause and therefore are accessible to galactic cosmic rays only through perpendicular diffus…

Transfer function analysis of ultraviolet observations of NGC 5548.

Koen, Chris

A general linear transfer function relating an input series (UV continuum flux) to an output series (emission-line flux) is presented. The methodology for fitting the transfer function is briefly described. The autocorrelation structure of IUE observations of NGC 5548 in different spectral bands is investigated, and appropriate univariate autoregr…

What can you Gain From Deconvolution? Observing Faint Galaxies With the Hubble Space Telescope Wide Field Camera

Elson, Rebecca A. W.; Schade, David J.

We describe experiments with deconvolutions of simulations of deep HST Wide Field Camera images containing faint, compact galaxies to determine under what circumstances there is a quantitative advantage to image deconvolution, and explore whether it is (1) helpful for distinguishing between stars and compact galaxies, or between spiral and ellipti…