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A model of convection and corotation in Jupiter's magnetosphere: Ulysses predictions
Cheng, A. F.
The Ulysses Jupiter encounter will include the first spacecraft pass through the dusk magnetosphere and will allow new tests of Jovian convection and corotation models. The Cheng and Krimigis [1989] model is extended to suggest that corotation lag occurs principally within the magnetodisk proper, which extends out to ∼60-70 RJ. It is pr…
HIPPARCOS photometry - FAST main mission reduction
Mignard, F.; Falin, J. L.; Froeschle, M.
In this paper we describe a photometric analysis of the Hipparcos data collected with the main detector. The overall principles of the photometric reduction are presented along with the first results. Both results at the transit level and over longer time scales are considered. We show that for a non-variable star of magnitude 8.5 an accuracy as g…
Pulse phase-resolved X-ray spectroscopy of the transient high-mass X-ray binary V 0332+53.
Coe, M. J.; Unger, S. J.; Lehto, H. J. +1 more
An analysis is conducted of Exosat observations of the transient binary X-ray pulsar V 0332 + 53 during a series of flares, which yielded simultaneous high energy and time resolutions. The results obtained are interpreted in terms of a system in which the line-of-sight from the earth is not close to the magnetic axis of the neutron star, and in wh…
CN Anomalies in Extremely Metal-Deficient Red Giants
Twarog, Bruce A.; Anthony-Twarog, Barbara J.; Shawl, Stephen J.
New photometric and UV spectroscopic data for the metal-deficient red giants CD -38 deg 245 and BD -18 deg 5550 are presented and discussed in light of recently noted photometric anomalies. From the IUE spectra it is aparent that the UV excess found in BD -18 deg 5550 is not the result of a hot companion. The IUE spectra, in conjunction with other…
A VLA 3.6 Centimeter Survey of N-Type Carbon Stars
Brown, Alexander; Luttermoser, Donald G.
The results are presented of a VLA-continuum survey of 7 N-type carbon stars at 3.6 cm. Evidence exists for hot plasma around such stars; the IUE satellite detected emission lines of singly ionized metals in the optically brightest carbon stars, which in solar-type stars indicate the existence of a chromosphere. In the past, these emission lines w…
Astrometric Performance Characteristics of the Hubble Space Telescope Fine Guidance Sensors
Benedict, G. F.; Franz, O. G.; Hemenway, P. D. +10 more
Each of the three Fine Guidance Sensors for the Hubble Space Telescope constitutes a sixth science instrument to be used for astrometry. We detail the tests and results used in choosing one of the three sensors to be the prime astrometer. The Astrometry Science team has chosen Fine Guidance Sensor (FGS) 3. FGS 3 produces position measurements on a…
Possible First Detection of Ultraviolet Pulses from an Intermediate Polar: V603 Aquila
Udalski, A.; Schwarzenberg-Czerny, A.; Monier, R.
We report possible independent detection of a pulsation in the UV continuum radiation of the intermediate polar star, V603 Aql, at 2.2 sigma level. Since the period of the pulsation of 62.9 minutes is very close to the period of X-ray and optical modulations discovered earlier, its detection combined with previous data confirms reality of UV, X-ra…
Ulysses particle observations of the March 1991 solar flare events
Heras, A. M.; Forsyth, R.; Balogh, A. +4 more
We present observations of energetic ions from the COSPIN instrument on the Ulysses spacecraft at 2.5 AU during the March 1991 series of solar flare events. The intensity profiles observed during this sequence of events were affected both by the presence of interplanetary shocks and large-scale discontinuities in the magnetic field, the low-energy…
The Origin of the Far-Ultraviolet Continuum in Solar and Stellar Flares
Bromage, G. E.; Doyle, J. G.; Phillips, K. J. H.
A continuum in the far-ultraviolet region observed in IUE spectra of dMe stars in a flaring state is discussed and compared with that observed in solar flares. Similar continuous emission observed in solar flare far-ultraviolet spectra has been identified with neutral silicon recombination radiation excited by intense lines. This also appears to b…
Applications of the infrared flux method to 3 cool AP stars (78 Virginis, 52 Herculis A and CS Virginis) and comparison of their energy distributions to model atmospheres.
Monier, R.
The infrared flux method proposed by Blackwell and Shallis (1977) is used, along with a comparison of the observed energy distribution to model grids, in order to determine the fundamental parameters of three cool Ap stars: 78 Vir, 52HerA, and CS Vir. The degree to which their energy distributions can be reproduced using currently available model …