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A Spectroscopic Search for Colliding Stellar Winds in O-Type Close Binary Systems. IV. IOTA Orionis
Wiggs, Michael S.; Gies, Douglas R.; Bagnuolo, William G., Jr.
We present H-alpha and He I 6678 A line profiles for the eccentric orbit binary Iota Ori. We have applied a tomography algorithm which uses the established orbital velocity curves and intensity ratio to reconstruct the spectral line profiles for each star. The He I profiles appear as pure photospheric lines, and H-alpha shows variable emission in …
Doppler tomography of O-type binaries: The physical properties of seven systems
Gies, D. R.; Penny, L. R.; Bagnuolo, W. G.
We have analyzed UV photospheric lines of seven O-type binaries, by means of crosscorrelation and Doppler tomographic methods, with the goal of estimating the physical properties of the individual stars. These systems are HD 1337 (AO Cas), HD 47129 (Plaskett's star), HD 57060 (29 UW CMa), HD 37043 (Iota Ori), HD 215835 (DH Cep), HD 152218, and HD …
Solar energetic particles in the intermediate region of the heliosphere
Kunow, H.; Wibberenz, G.; Heber, B. +2 more
Energetic particle increases in the energy range 4 to 130 MeV observed by the Kiel Electron Telescope (KET) during the in-ecliptic part of the ULYSSES mission between 1 and 5.4 AU differ distinctly from their appearance in the inner heliosphere inside 1 AU. Prompt events are rare, and for most of the events velocity dispersion is lacking. The obse…
The Orbit and Companion of the Cepheid S SGE: A Probable Triple System
Evans, Nancy R.; Welch, Douglas L.; Slovak, Mark H. +2 more
New radial velocities for the classical Cepheid S Sge have been obtained and combined with previous observations to derive a new orbit. The revised orbital elements are: gamma, -10.3 +/- 0.4 km/s; K, 15.5 +/- 0.2 km/s; e, 0.23 +/- 0.02; omega, 203.1 +/- 4.2 deg; T0, 39902.3 +/- 6.6 JD; P, 675.79 +/- 0.18 days; f(m), 0.239 +/- 0.010 solar masses; a…
Langmuir wave decay and collapse in the Jovian foreshock
Kellogg, Paul J.; Thiessen, Jerold P.
Langmuir waves are known to be created upstream of planetary bow shocks by the two-stream instability driven by sunward-streaming particles. In this paper we examine Langmuir waves detected by Ulysses' Unified Radio and Plasma wave experiment (URAP) upstream of Jupiter. Wave envelopes qualitatively consistent with collapsed Langmuir waves are comm…
Possible discovery of threeγ-ray pulsars
Yu, K. N.; Young, E. C. M.; Lu, Tan +1 more
The possible discovery of threeγ-ray pulsars 0656 + 14, 0950 + 08, and 1822 - 09 based on COS-B data analysis is reported. Their light curves, the other related features, and the methods leading to these results are also given. Among these three pulsars, PSR 0656 + 14 is the most significant one for being aγ-ray pulsar.
Observations of Nearby Interstellar Gas and Dust in the Direction toward the Globular Cluster omega Centauri
Bates, B.; Wood, K. D.
High-resolution spectra of Na I D interstellar lines are presented for six stars which lie within 4°.0 of the globular cluster ω Centauri and at distances in the approximate range 100-600 pc. For one star (HD 116226) we discuss also the Ca II K line profile and spectra obtained with lUE. Sky flux images of the ω Cen field show considerable structu…
Observable implications of tearing-mode instability in Jupiter's nightside magnetosphere
Zimbardo, G.
We consider the implications on observations of tearing-mode instability in Jupiter's nightside magnetosphere. Theoretical developments of the tearing instability are briefly discussed. Using a self-consistent axisymmetric magnetic field model based on the Voyager data, it is found that magnetic reconnection driven by the internal magnetospheric e…
Electron density and temperature in the Io plasma torus from Ulysses thermal noise measurements
Moncuquet, Michel; Meyer-Vernet, Nicole; Hoang, Sang +2 more
During the Ulysses flyby of Jupiter, the spacecraft crossed the outer part of the Io plasma torus along a basically North-to-South trajectory at a Jovicentric distance of about 8 RJ. The quasi-thermal noise measured by the Unified Radio and Plasma Wave (URAP) experiment is used to deduce the electron density and temperature along the tr…
An extended correlation between the Balmer and soft X-ray emission from solar and stellar flares.
Butler, C. J.
The integrated soft X-ray (8-12 Å) fluxes for solar flares, given by Thomas & Teske (1971), have been scaled to the equivalent EXOSAT (0.04-2.0 keV) fluxes using spectra obtained from a variety of rocket-based experiments and a model by Mewe for a 1.5 keV plasma. The data show good agreement with the soft X-ray-Hγ correlation established earli…